Abstract:
The invention provides methods of disintegrating or reducing the particle size of elemental materials, such as various forms of carbon, and organic crystals that contain minerals and that do not contain minerals. The method include the steps of entraining the material in a gas flow through an inlet of a housing, subjecting the flowing material to a plurality of alternating pressure increases and decreases within the housing, disintegrating the flowing material with the pressure increases and decreases, thereby reducing the mean particle size of the material, and discharging the disintegrated material though an outlet of the housing.

Description:
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS 
     This patent application is a continuation-in-part of copending U.S. patent application Ser. No. 09/694,708, filed Oct. 23, 2000, now abandoned, which is a continuation of Ser. No. 09/290,483, filed Apr. 12, 1999 and issued as U.S. Pat. No. 6,135,370, which is a continuation of Ser. No. 08/897,015, filed Jul. 18, 1997 and now abandoned, all three to Charles A. Arnold and entitled “Apparatus And Methods For Pulverizing Material Into Small Particles.” 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to methods for producing ultra-fine particles of amorphous elemental and compound materials in amorphous or crystalline form. 
     BACKGROUND OF THE INVENTION 
     Small particle size material has a large surface to volume ratio. For this reason, chemical processes often work better by using small size particles for feed stock material. Small particle size is also important for pharmaceuticals and nutritional supplements, which are taken up by the body more easily and effectively when in small particle sizes. 
     One such material with many industrial uses is carbon black, which is an amorphous form of pure carbon. Carbon black is useful as a carbon feed stock for chemical processes, e.g. in plastic production, in compounding of rubber, and in the production of inks and pigments. Typically, carbon black is produced by burning acetylene and other organic fuels under low oxygen conditions. This is energy intensive and creates gas by-products that are undesirable. 
     There is a growing interest in recovery of carbon from scrap material so it can be recycled in useful ways. One such source of carbon is from pyrolyzed scrap vehicle tires. Millions of kilograms of char (essentially pure carbon) are potentially available from tire “waste.” Chars having different properties and characteristics can be made consistently by changing process parameters, such as pyrolysis temperature, heating rate, pyrolysis time, the rotating speed of the reactor, and the presence or absence of additives. 
     Such pyrolytic char particles typically range in size from about one micron to over one millimeter. Carbon particles of this size range are too large for use in compounding of tire tread rubber, plastics and other materials or for use as pigment in printers. The char must therefore be made into particle sizes of about one micron or less in order to generate carbon that can be used to produce new products. For most large volume uses, such fine particle sizes are desirable or required. Since thousands of tons of fine carbon particles are used in various industries, machines that can process large amounts of material are required. 
     Other hard materials that are crystalline or amorphous in form are generally difficult to grind into smaller particle sizes that would be useful for uses such as food processing or nutritional supplements. Such materials include crystals of organic molecules containing minerals and non-mineral containing organic compounds. For most of these materials a particle size of less than about 50 microns is highly desirable. 
     BRIEF SUMMARY OF THE INVENTION 
     The invention provides methods for producing useful, small particle forms of both elemental and compounded materials using resonance disintegration. The materials may be in either amorphous or crystalline form. In most cases, a fine, flowable powder is produced. 
     In one aspect, the invention provides a continuous flow method of reducing the mean particle size of a particulate carbon material that consists of at least about 90% carbon by weight. The method includes entraining the carbon material in a gas flow through an inlet of a housing, subjecting the flowing carbon material to a plurality of rapid alternating pressure increases and decreases within the housing, disintegrating the flowing carbon material with the pressure increases and decreases, thereby reducing the mean particle size of the carbon material, and discharging the disintegrated carbon material though an outlet of the housing. The carbon material can comprise an amorphous form of carbon, such as carbon black or pyrolyzed carbon char, or a crystallized form of carbon, such as graphite. Processing as recited above appears to produce a more hydrophilic form of carbon particle. In one embodiment, the method can include coating the carbon particles with an adherent material, such as oil, while the particles are flowing though the housing. 
     In embodiments where the amorphous form of carbon is carbon char, the median volume distribution of the sizes of the discharged carbon particles is in a range of about 1.6-2.7 microns when dispersed in isopropanol. Such discharged carbon particles when dispersed in isopropanol are characterized by at least about 93% of the particles being below about 30 microns in size, by about 60-90% of the particles being below about 5 microns in size, and by about 5.3-16% of the particles being below about 1 micron in size. When dispersed in water, the median volume distribution of the sizes of the discharged carbon particles made from carbon char is less than about one micron, and preferably about 0.52-0.88 microns or less. When dispersed in water, the discharged carbon particles made from char are characterized by essentially 100% of the particles being below about 30 microns in size, by about 75% of the particles being smaller that about 5 microns in size, and by about 46-51% of the particles by volume being below about 1 micron in size. 
     When the elemental amorphous material is carbon black, the median volume distribution of the sizes of the discharged carbon particles is less than about 3 microns, and preferably from about 0.52-2.7 microns in size. The median volume distribution of the discharged carbon particles made from carbon black is about 0.52 microns when dispersed in water. The discharged carbon particles when dispersed in water are characterized by essentially 100% of the particles being about 5 microns or less, and by about 90% of the particles being about 1 micron or less. 
     The invention, in yet another aspect, provides a powdered form of amorphous carbon, consisting essentially of particles that when dispersed in water are characterized by essentially 100% of the particles having a size of about 5 microns or less, and by about 90% of the volume of the particles having a size of about 1 micron or less. The particles can be further characterized by having a median volume distribution of about 0.52 microns. 
     In still another aspect, the invention provides a powdered form of carbon char, consisting essentially of particles that when dispersed in water are characterized by essentially 100% of the particles being about 30 microns or less. The powdered carbon char particles can be further characterized by about 75% of the particles by volume being about 5 microns or less in size, and by at least about 46% of the particles by volume being about one microns or less in size 
     In another aspect, the invention provides a continuous flow method of reducing the particle size of crystals of an organic molecule, wherein the initial particle size of the crystals is at least about +80 mesh. The method steps include: entraining the crystals in a gas flow through an inlet into a housing; subjecting the crystals to a plurality of pressure increases and decreases while flowing through the housing; disintegrating the flowing crystals with the pressure increases and decreases, thereby reducing the mean particle size of the crystals; and discharging the disintegrated crystals though an outlet of the housing, wherein substantially all the discharged crystals have a particle size that is about −270 mesh. In some embodiments, wherein substantially all of the discharged crystals have a particle size that is less than about 20 microns. In other embodiments, most of the discharged crystals have a particle size that is less than about 4 microns. 
     The organic molecule can contain a mineral In certain features, the organic molecule is selected from the group consisting of calcium citrate, magnesium citrate and methylsulfonylmethane. 
     In other embodiments wherein the organic molecule does not contain a mineral. Such organic molecule may be selected from the group consisting of creatine monohydrate, ipriflavone, and zein. 
     The invention provides many advantages. The ultrafine carbon particles produced according to the invention have a very small size distribution, even smaller than carbon black, when dispersed in water. The small particle size and the easy dispersion in water makes these carbon particles particularly useful for making inks and dyes for use in ink jet and other types of printers. The fine particle size carbon material is also very useful as a feed-stock for compounding tread rubber, plastics, and the like. 
     The organic materials that are reduced in size are more easily put into solution than other forms of such compounds. This is advantageous when using these substances in food processing or as dietary food supplements. The smaller particle size enables these materials to be more readily absorbed in the body. 
     Other objectives and advantages of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present invention, and together with the description serve to explain the principles of the invention. In the drawings: 
     FIG. 1 is an elevation view of a resonance disintegration system according to the invention; 
     FIG. 2 is a top plan view of the resonance disintegration system illustrated in FIG.  1 . 
     FIG. 3 is an elevation view of a rotor assembly housing of the resonance disintegration system illustrated in FIG. 1; 
     FIG. 4 is a cross sectional view through line  4 — 4  of FIG. 3, and in which a distributor rotor is shown in plan view; 
     FIG. 4A is a detail of FIG. 4; 
     FIG. 5 is a cross sectional view through line  5 — 5  of FIG. 4, showing the rotor assembly within the rotor assembly housing, with a second feed chute included; 
     FIG. 6 is a bottom plan view of the rotor assembly housing; 
     FIG. 7 is an expanded view of the distributor rotor; 
     FIG. 8 is a top plan view of an orifice plate of the rotor assembly; 
     FIG. 9 is a top plan view of a rotor; 
     FIGS. 10A and 10B are elevation and plan views, respectively, of a rotor assembly support pin; 
     FIG. 11 is a plan view of a portion of a rotor with another embodiment of a rotor vane; 
     FIG. 12 is a cross sectional view through line  12 — 12  of FIG. 11; 
     FIGS. 13A and 13B are micrographs of carbon black particles produced by resonance disintegration of carbon char granules. 
     FIGS. 14A and 14B are graphs of the volume frequency vs. diameter for standard reference carbon black N660 dispersed in water before resonance disintegration and after resonance disintegration, respectively; 
     FIGS. 15A and 15B are graphs of the volume frequency vs. diameter for the carbon black samples dispersed in isopropanol before resonance disintegration and after resonance disintegration, respectively; 
     FIGS. 16A,  16 B, and  16 C are graphs of the volume frequency vs. diameter for pyrolytic carbon char dispersed in water before resonance disintegration, after resonance disintegration once, and after resonance disintegration twice, respectively; and 
     FIGS. 17A,  17 B and  17 C are graphs of the volume frequency vs. diameter for the pyrolytic carbon char samples dispersed in isopropanol before resonance disintegration, after resonance disintegration once, and after resonance disintegration twice, respectively. 
    
    
     While the invention will be described in connection with certain preferred embodiments, there is no intent to limit it to those embodiments. On the contrary, the intent is to cover all alternatives, modifications and equivalents as included within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The invention provides methods of producing ultrafine particles from organic and inorganic compounds that are in crystalline or amorphous states. In addition the invention provides methods of producing ultrafine particles of elemental nonmalleable materials in crystalline or amorphous states. In this specification the term “micronized” means particle sizes of less than about 50 microns (about −270 mesh). The materials are reduced in size by resonant disintegration (RD). RD produces powerful shock waves that applies destructive resonance to particles as they pass through a RD mill, which is described below. The shock waves are generated by turning rotors within a multi-sided chamber. The rotors, which alternate with a series of orifice plates, cause material flowing with gas through the chamber to suffer rapidly alternating compressive and decompressive forces as they are driven through the RD mill by the spinning rotors. The RD mill provides thousands of pulse waves and incremental increases in the magnitude of the shock waves as the flowing material passes through subsequent levels of rotors and orifice plates. Material being processed by the RD mill is also exposed to considerable shear forces and piezoelectric forces. Resonance forces are augmented by vortex-generated shearing forces that are phased for delivery just at the time particles approach and exceed their inherent limit of elasticity. Design features provide for phasing of forces such that energy transfer to the machine itself is greatly minimized, thus enhancing the efficiency and smoothness of operation. It is believed that material being processed by the RD mill are also subject to substantial pulsed piezoelectric forces. 
     Using the forces described above it is clear that the RD mill reduces particle size by fragmenting resonance forces that vibrate and tear particles apart. This is in contrast with the crushing forces generated in hammer, ball and jet mills. RD cleaves particles apart along various boundaries. For example, crystalline materials are broken along planes of the crystalline lattice structure that are weakest, or most susceptible to separation at a given resonance frequency. Once the elastic limit of a given material is exceeded, the particle is disintegrated into smaller particles. Hard, crystalline materials with little elasticity are therefore readily micronized, whereas highly elastic materials, such as certain types of rubbers and plastics, are more resistant to fragmentation into fine particle size, but can still be significantly reduced in size. 
     The medium used to conduct RD is commonly atmospheric air. Other gases, such as nitrogen and carbon dioxide, as well as water/gas mixtures can be accommodated. Whatever the media, material flows through the RD mill in less than a second and, depending upon the material, 200-3500 kg can be processed per hour. Owing to the RD mill design, the material is entrained with gas flowing along the surfaces and edges of the rotors and orifice plates such that contact with the internal parts of the RD mill and energy transfer to the machine is minimized. This important feature is called a Coanda flow. In fact, most of the material at any one instant is not in physical contact with the machine. This markedly reduces the transfer of metal from the RD mill to the product, as is possible with traditional impact milling equipment. 
     The operational speed and direction of rotation of the rotors can be varied over a continuous range, typically between about 1000-5000 rpm. This provides a mechanism for fine-tuning the RD milling process for different materials, as different rotation speeds generate different frequencies and amplitudes of compression and decompression. 
     In one example, the invention provides ultrafine particles of carbon having an average primary particle size of about 38 nanometers (nm) in aggregates and agglomerates ranging in size from about 1 μm to 10 μm. Over 70% of the carbon particulate volume is below 1 μm when dispersed in water. In other examples, the invention provides micronized crystals of organic molecules containing minerals, such as magnesium citrate, calcium citrate, and methylsulfonylmethane, and micronized non-mineral containing organic compounds, such as creatine monohydrate and ipriflavone (7-isopropoxy-isoflavone). 
     In the following sections, an RD mill will be described first. Methods of using the RD mill to make ultrafine particles of carbon and other materials will be described next, with descriptions of the materials produced and their uses. 
     Resonance Disintegration Mill 
     An RD mill is described in U.S. Pat. No. 6,227,473, the entire disclosure of which is included herein by reference. Referring now to FIGS. 1 and 2, a RD mill  10  includes a housing  12  containing a rotor assembly  38 , which will be described in detail below. Housing  12  is surrounded by a cylindrical shield  14  that is supported from an annular plate  16  by a free-standing support frame  18  on a concrete slab  19 . Annular plate  16  is welded to shield  14  and secured to frame  18  with bolts  20 . 
     Frame  18  also supports a motor assembly  22 , which provides rotational power to the rotor assembly via a single four-grooved belt  24  coupling to a variable mechanical sheave  26 . Sheave  26  is connected to a rotor shaft  28  that extends through housing  12 . Rotor shaft  28  is fabricated from 2 inch (5.1 cm) diameter, 4140 steel rod. Motor assembly  22  includes a 100 —hp , 480 V, three-phase motor  30  that has a variable frequency drive control  32 . Motor assembly  22  receives power from a fusible disconnect  34 . The variable frequency drive and control  32  permits the speed of rotor shaft  28  to be continuously varied between about 600-5000 revolutions per minute (rpm). A sprocket assembly  36  attached to shaft  28  is used to measure the actual rotational speed of shaft  28 . A shroud (not shown) can be used to cover belt assembly  24 . Alternatively, motor  30  can be configured for direct, variable-speed drive. 
     Referring now also to FIGS. 3 and 4, housing  12  has nine longitudinally extending side walls  40  forming a regular polygon shape in latitudinal cross section. The interior surface of housing  12  has an inscribed diameter of approximately 23.5 inches (59.7 cm). Sides  40  form 40° apices, or interior corners  42 , where they meet. Sides  40  and interior corners  42  extend longitudinally between a top plate  44  and a bottom plate  46 . Top and bottom plates  44 ,  46  are approximately 30.5 inches (77.5 cm) apart. Top plate  44  is rigidly tied to shield  14  with three strap assemblies  48  (FIGS.  1  and  2 ). Strap assemblies  48  each include a bracket  50  welded to the outer surface of shield  14 , a rigid strap  52 , and bolts  54 ,  56  connecting strap  52  to bracket  50  and top plate  44 , respectively. 
     Sides  40  are formed of three panels  60 ,  62 ,  64 , each including two full sides  40  and two partial sides  40 , and three interior corners  42 . Referring now also to FIG. 4A, each pair of panels, e.g.,  60  and  62 , can be joined with an overlapping seam  66  located about midway between corners  42 . Brackets  68  are welded to panel  60 , and brackets  70  are welded to panel  62  adjacent to seam  66 . Bracket pairs  68 ,  70  are tied together by fasteners, for example, with bolts  72  and nuts  74 . A sealing joint material such as, for example, a silicon based sealant, can be used at seam  66  and other joints between pieces of housing  12  to make housing approximately air-tight. 
     Referring again to FIGS. 2 and 3, bottom plate  46  is supported from a portion of annular plate  16  that extends radially inward a short distance from shield  14 . A gasket (not shown) providing a liquid seal is placed between annular plate  16  and bottom plate  46 . A J-bolt arrangement (not shown) can be employed for ensuring a positive seal with the gasket. Bottom plate  46  is secured to panels  60 ,  62 ,  64  with nine threaded fasteners  65  that extend through apertures formed in respective fittings  67  attached to panels  60 ,  62 ,  64 , and that screw into threaded holes  58  arrayed around the periphery of bottom plate  46 . Top plate  44  is bolted to threaded fittings  75  on panels  60 ,  62 ,  64  with threaded fasteners  76 . 
     A feed chute  78  for introducing material to be micronized into housing  12  extends through an aperture  80  in top plate  44 . For clarity of illustration, feed chute  78  is illustrated at a position in FIG. 2 that is different from the position depicted in FIG.  1 . Feed chute  78  includes a rectangular shaped tube  82  that is oriented relative to the plane of top plate  44  at an angle of approximately 44 degrees. Feed chute  78  also has a funnel  84  at its top end and a bracket  86  for attachment to top plate  44 . Tube  82  is approximately 13.25 inches long, extends approximately 1.375 (3.5 cm) inches below the bottom side of top plate  44 , and has interior dimensions of 3×4 inches (7.6×10.2 cm). Tube  82  includes a flange  85  for attaching feed chute  78  to top plate  44 , e.g., with threaded fasteners. 
     The rotor assembly  38  will now be described in detail with reference to FIGS.  1  and  4 - 6 . Rotor assembly  38  includes a rotatable shaft  28  that extends longitudinally through housing  12 . Shaft  28  extends through a top bearing assembly  86  that is bolted to top plate  44 . Sprocket speed indicator assembly  36  and sheave  26  are positioned on shaft  28  above top bearing assembly  86 . A bottom bearing assembly  88  is bolted to the bottom side of bottom plate  46 . Shaft does not extend through bottom bearing assembly  88 . 
     Within housing  12 , there are six longitudinally spaced rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100 , each being fixed to a respective hub  102 ,  104 ,  106 ,  108 ,  110 ,  112  that is coupled to shaft  28  by two keys (not shown). Spacers  114 ,  116 ,  118 ,  120 ,  122 , which are also keyed onto shaft  28 , are positioned between adjacent pairs of hubs  102 ,  104 ,  106 ,  108 ,  110 ,  112 . Spacers  124  and  126  are positioned adjacent top plate  44  and bottom plate  46 , respectively. Spacer  124  is also secured to shaft  28  with a set screw (not shown). Shaft  28  can be fabricated is made of 2 inch diameter 4140 alloy steel. The diameter of each spacer is approximately 3.5 inches (8.9 cm). The longitudinal position of one or more than one of rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100  can be adjusted by changing the length one or more of spacers  114 ,  116 ,  118 ,  120 ,  122 ,  126 . 
     Orifice plates  128 ,  130 ,  132 ,  134  and  136  are positioned between adjacent pairs of rotors  90 ,  92 ,  94 ,  96 ,  98  and  100 . Each of orifice plates  128 ,  130 ,  132 ,  134 ,  136  includes a central aperture, which, with its respective spacer  114 ,  116 ,  118 ,  120 ,  122 , provides an annular shaped orifice  138 ,  140 ,  142 ,  144 ,  146  therebetween. Orifice plates  128 ,  130 ,  132 ,  134 ,  136  each extend to sides  40  of housing  12  such that there is no gap between the edge of an orifice plate and the housing sides  40 . A gasket or other sealing means can be used to assure that there is no space through which a gas or liquid can flow between the orifice plates and the housing. 
     In the described embodiment, each of shield  14 , annular plate  16 , top plate  44 , bottom plate  46 , panels  60 ,  62 ,  64 , rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100 , and orifice plates  128 ,  130 ,  132 ,  134 ,  136  are fabricated of 0.5 inch (1.27 cm) thick low-carbon steel, such as, for example, 1020 steel. These components may be fabricated from different materials, including harder materials and softer materials, depending upon the intended application for RD mill  10 . 
     Referring now also to FIG. 7, the topmost rotor  90 , which will also be referred to as a distributor rotor, is positioned closest to where material is fed into housing  12  via feed chute  78 . Distributor rotor  90  includes a distributor rotor plate  148  having a regular pentagonal-shaped peripheral edge forming five apices, or outside corners  150 . Five distributor rotor vanes  152  extend upwards toward top plate  44  from the top side of distributor rotor plate  148  (only three vanes are shown in FIG. 7 for clarity). Each distributor rotor vane  152  also extends approximately radially inward from an outside corner  150  to hub  102 . Vanes  152  can be fixed to distributor rotor plate  148  and hub  102  by welding. Alternatively, each distributor rotor vane  152  can fit into a corresponding slot  154  formed in distributor rotor plate  90 , and secured by threaded fasteners  156 , e.g., bolts, that extend through apertures  158  in distributor rotor plate  90  and screw into corresponding threaded holes  160  in distributor rotor vane  152 . An upper edge  162  of each distributor rotor vane  152  is sloped upwards from an elevation of about 1 inch (2.5 cm) at  102  to an elevation of about 1.5 inches (3.8 cm) near the periphery of plate  148 . A pentagon-shaped distributor ring  164 , which is about 1.5 inches (3.8 cm) wide, is welded to the upper edges  162  of distributor rotor vanes  152 . 
     In the described embodiment, each of distributor rotor plate  148 , distributor ring  164 , and distributor rotor vanes  152  are fabricated from 0.5 inch (1.27 cm) low-carbon steel plate. In other embodiments, such parts and the housing can be fabricated of stainless steel or other suitable materials. Distributor rotor is circumscribed by a 17 inch (43.2 cm) diameter circle and is approximately 2.7 inches (6.9 cm) high. Distributor ring  164  is located approximately 1.625 inches (4.13 cm) below top plate  44  and approximately 0.25 inches (0.63 cm) below a discharge opening  166  of feed chute  78 . Discharge opening  166  of feed chute  78  is positioned such that when a center of a chord of distributor ring  164  is aligned with discharge opening  166 , a radially innermost edge  168  of discharge opening  166  extends about 0.5 inches (1.27 cm) inwardly beyond an inner edge  170  of distributor ring  164 . When a corner  150  of distributor rotor  90  is aligned with feed chute  78 , the outside of discharge opening  166  is completely inside distributor ring  164 . This provides a large area to feed material into slots between distributor rotor vanes  152 , and discharges the material from feed chute  78  onto rotor  90  as radially distant from hub  102  as possible. For reasons that will be discussed below, each vane  152  is positioned such that when rotor assembly is spinning, a trailing outer edge  172  of each distributor rotor vane  152  is shaped to be about aligned with the peripheral edge of distributor rotor plate  148  at a trailing edge of an apex  150 , either without any overlap or with distributor rotor vanes  152  extending slightly over the edge of distributor rotor plate  148 . 
     Other rotors  92 ,  94 ,  96 ,  98 ,  100  are designed differently from distributor rotor  90 , but similarly to each other. Rotor  94  will be described as an example, with reference to FIG.  8 . Rotor  94  includes a rotor plate  174  having a regular nine-sided polygonal peripheral edge  176  forming nine apical corners  178 . Rotor plate  174  is welded or otherwise rigidly coupled to hub  106 . Rotor  94  also includes nine curved vanes  180 , each extending approximately radially inward toward hub  106  from a respective one of the apical corners  178 . Vanes  180  are approximately six inches long and extend approximately one inch above rotor plate  174 , which is about 0.5 inches (1.27 cm) thick. For most uses of RD mill  10 , the interior curve of each of vanes  180  faces into the direction in which rotor assembly turns, although in some applications a reverse rotation provides better results. Rotor plate  174  is fabricated from 0.5 inch (1.27 cm) low-carbon steel plate, and vanes  180  are fabricated from 0.5 inch (1.27 cm) wall, 8 inch (20.3 cm) outer diameter steel tubing. Vanes  180  are set in respective 0.125 inch (0.32 cm) deep grooves (not shown) formed on an upper face of rotor plate  174 , and secured in place with three threaded fasteners (not shown) that extend through apertures formed in rotor plate  174  (not shown), in a manner similar to that described above with reference to distributor rotor  90  illustrated in FIG.  7 . This arrangement permits simple removal and replacement of vanes  180 . Alternatively, rotors  180  may be welded to rotor plates  174 , or otherwise affixed to rotor plates  174 . Outer trailing edges  182  of vanes  180  are beveled at an angle to align with peripheral edge  176  of rotor plate  174  such that there is no overlap between rotor plate  174  and vane  180 , or so that trailing edge  182  extends slightly over edge  176  of rotor plate  174  on the trailing side of an apical corner  178 . 
     The other rotors, rotors  92 ,  96 ,  98  and  100 , are configured similarly to rotor  94 , each having a nine-sided peripheral edge  176  and curved vanes  180  extend radially inward from apical corners  178  toward respective hubs  104 ,  108 ,  110  and  112 . In the embodiment illustrated in FIG. 5, rotors  92 ,  94 ,  96 ,  98  and  100  are circumscribed by circles having diameters of 17, 19, 21, 21, and 21 inches, respectively. Each of vanes  180  is approximately 6 inches (16.2 cm) long about its outer perimeter and shaped at its apical corner  182  so that there is little or no overlap between vane  180  and rotor plate  174  at its trailing edge  182 . Each of rotors has a height of approximately 1.5 inches (3.8 cm). Because rotor  92  is smaller than the other rotors and vanes  180  are the same size on all rotors  92 ,  94 ,  96 ,  96 ,  100 , each of vanes  180  on rotor  92  extend approximately to hub  104 , whereas vanes  180  on rotors  94 ,  96 ,  98 ,  100  do not extend all the way to hubs  106 ,  108 ,  110 ,  112 , respectively, a gap being provided therebetween. 
     Referring now to FIG. 11, each of vanes  180  may be positioned to provide a small overhang  220  over the edge  176  of the rotor plate to which it is attached. Overhang  220  would be no more than about a thirty-second of an inch, and would enhance the Coanda flow. Note that vane  180  illustrated in FIG. 11 is also positioned such that overhang  220  is shaped similar to edge  176  of rotor plate  174 , and an outer tip  222  of its leading surface  224  is positioned about over apical corner  178 . The arrow in the figure indicates a direction of rotation. 
     Referring now to FIG. 12, vanes  180  may also be modified to have a curved profile, like a turbine blade, on its leading surface  224  with respect to a direction of rotation (arrow) to provide a more efficient pumping action. 
     Referring now also to FIG. 9, orifice plate  128  can be fabricated from 0.5 inch (1.27 cm) low-carbon steel plate. Its peripheral edge  184  forms a nine-sided polygon sized to fit closely against sides  40  of housing  12 . Orifice plate  128  includes a central aperture  186  formed by inner rim  188 , which, with spacer  114 , provides annular-shaped orifice  138  therebetween. Orifice plates  130 ,  132 ,  134 , and  136  are similarly configured. Orifice plates  128 ,  130 ,  132 ,  134 , and  136  have apertures  186  with diameters of 7, 8, 9, 10 and 11 inches (17.8, 20.3, 22.9, 25.4, and 27.8 cm), respectively. 
     Referring back to FIGS. 4 and 5, and also to FIGS. 10A and 10B, orifice plates  128 ,  130 ,  132 ,  134 ,  136  are supported independently of panels  60 ,  62 ,  64  by support pins  190 . Support pins  190  can be fabricated from 2 inch (5.1 cm) diameter steel rod. Three equally spaced apart pins  190  are positioned between each neighboring pair of the orifice plates. Each support pin  190  is located at an apical corner  192  of an orifice plate so that it is adjacent an interior corner  42  of housing. As shown in FIGS. 5 and 9, support pins  190  on one side of an orifice plate, e.g. orifice plate  128 , are offset by one apex (40°) from support pins  190 A on the other side of that orifice plate. 
     Support pins  190  are attached to the orifice plates by threaded fasteners  194 , e.g., bolts, that extend into counter-sunk through holes (not shown) formed in the orifice plates and into threaded holes  196  formed in pins  190 . Three support pins  190  that are attached to an upper side of orifice plate  128  can also be attached to top plate  44  with threaded fasteners. For example, bolts  56 , which are also employed to hold straps  52  as described above with reference to FIG. 2, can be employed to fasten to these three pins  190 . Three support pins  190  that are attached to a bottom side of orifice plate  136  can also be attached to bottom plate  46 . Bottom plate  46  includes three apertures  198  through which threaded fasteners  200  (shown in FIG. 5) can be inserted for fastening to these three pins  190 . 
     Referring again to FIG. 6, bottom plate  46  includes a web  202  forming four apertures  204  through which pulverized material is discharged from housing  12 . A 23 inch (58.4 cm) diameter skirt  206  depends from bottom plate  46  just outside of apertures  204 . Web  202  supports rotor assembly  38  from bottom bearing assembly  88 , which is bolted to web  202 . The size of web  202  is made as small as possible to maximize the size of apertures  204  within skirt  206 . 
     The diameter of skirt  206  is sized to fit into a 55 gallon open barrel  208 , which rests on rollers  209 . A fabric belt  210  is employed between skirt  206  and barrel  208  to inhibit fine pulverized particles from escaping. Skirt  206  includes four apertures  212  (only two shown in FIG.  3 ). Each aperture  212  includes a bolt circle employed for attaching a respective 6 inch (15.2 cm) diameter tube  214  (only two shown in FIGS.  1  and  2 ). Tubes  214  extend approximately radially outward from skirt  206 , and each tube  214  has a fabric filter bag  216  removably attached to it. Air is exhausted from RD mill  10  through tubes  214 . Filter bags  216  catch fine particles and allow air to pass through. 
     In the described embodiment, rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100  and orifice plates  128 ,  130 ,  132 ,  134 ,  136  are positioned as follows. The top surfaces of orifice plates  128 ,  130 ,  132 ,  134 , and  136  are respectively located approximately 2.875, 2.125, 1.875, 1.625, and 1.375 inches (7.3, 5.4, 4.8, 4.1 and 3.5 cm) below the bottom surfaces of respective rotors  90 ,  92 ,  94 ,  96 , and  98 . Orifice plates  128  and  130  are approximately 5 inches (12.7 cm) apart; orifice plate  130  and  132  are approximately 4.5 inches (11.4 cm) apart; orifice plates  132  and  134  are approximately 4 inches (10.2 cm) apart; and orifice plates  134  and  136  are approximately 3.5 inches (8.9 cm) apart. The tops of vanes  180  on rotors  92 ,  94 ,  96 ,  98  and  100  are about 1.375, 1.187, 0.875, 0.625, and 0.5 inches (3.5, 3.0, 2.2, 1.6 and 1.3 cm) below respective orifice plates  128 ,  130 ,  132 ,  134 , and  136 . Rotor  100  is positioned approximately 1.75 inches (4.4 cm) above bottom plate  46 . Rotors  92 ,  94 ,  96 ,  98  and  100  are rotated relative to their next nearest rotor by about 7.2 degrees. 
     It can be seen that rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100  of rotor assembly  38  have sizes that generally increase with increasing distance from a top end of housing  12  through which material to be pulverized or otherwise processed is introduced into housing  12 . The smallest rotors  90 ,  92  are located closest to top plate  44 , the largest rotors  96 ,  98 ,  100  are positioned closest to bottom plate  46 , and an intermediate sized rotor  94  is positioned about midway between top plate  44  and bottom plate  46 . This arrangement is particularly adapted for disintegrating large size objects. If the feed material comprises smaller sized particles, such as pyrolytic carbon char, the rotors could be of a more uniform, larger size. In some applications, it may be advantageous to have rotors that are all the same size, or to alternate between larger and smaller rotors in some fashion. 
     In addition, orifices  138 ,  140 ,  142 ,  144 ,  146  are of generally increasing size with increasing distance from the top end. This arrangement is used to maintain a negative back pressure at each stage. For other applications, this arrangement could be reversed, the orifices could be a more uniform size, or the orifice sizes could be varied in a different manner from one end of housing  12  to the other. 
     The spacing between each orifice plate and the rotor next below it generally decreases with increasing distance from top to bottom. Moreover, the rotors and orifice plates are positioned such that the spacing between adjacent orifice plates generally decreases from top to bottom. This decreases the volume in stages between the top and bottom of rotor assembly  38 . 
     Material flowing through an orifice in RD mill  10  first undergoes a velocity increase and an accompanying decrease in pressure. Then, because the available volume decreases at each succeeding stage, the material flowing through RD mill  10  experiences a rapid compression, which in turn can cause a rapid increase in pressure and/or temperature. The size of the orifice is increased with each succeeding stage to provide a pressure immediately downstream of an orifice that is lower than the pressure immediately upstream the orifice. This negative back pressure that is maintained across each orifice helps to maintain the flow. 
     As best understood, material introduced into RD mill with rotor assembly spinning at speeds of approximately 1000 revolutions per minute (rpm) or greater are disintegrated primarily by pressure changes, including shock waves, generated within housing  12 . Observations indicate that material fed into feed chute  78 , as well as air entering through feed chute  78 , is accelerated rapidly and is then entrained into a fluid-like flow through the spinning rotor assembly  38 . It appears that the material in the flow is almost immediately subjected to a rapid-fire succession of shock waves, the first of which may begin to break up the feed-stock material even before it reaches the distributor rotor. 
     The spinning rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100  create a very strong air flow through housing  12 . It appears that material fed into RD mill  10  through feed chute  78  is entrained in this flow. (In fact, the air flow actually increases for a given rotor speed when a solid particulate material is being processed.) The material apparently flows, with the air or gas flow, through RD mill  10  making minimal contact with sides  40  of housing  12  or with orifice plates  128 ,  130 ,  132 ,  134 ,  136 . This is due to the flow being influenced by the Coanda effect to closely follow the contours of the rotor periphery  174  and orifice rims  188 . For this reason, the flow through RD mill of material and air is called a “Coanda flow.” The Coanda effect helps to reduce high-angle contacts between the flowing material and the component parts of RD mill  10 , and thereby to reduce wear on these parts, to reduce contamination of the material being milled, and to preserve the surface characteristics of the milled material. Distributor ring  164  acts as a shroud to enhance the Coanda effect. 
     The Coanda flow rapidly changes direction as it rounds the peripheral edge of each rotor and the rim of each orifice, alternating between a flow that is directed radially outward and a flow that is directed radially inward. The sizes of the orifices increase with each succeeding stage to maintain a negative back pressure throughout rotor assembly  38 , which helps to keep the velocity of air and particles sufficiently high to maintain the Coanda flow. 
     Observations made when milling hard materials, such as ceramic balls, indicate that when vanes  152 ,  180  are not positioned on the trailing side of apical corners  150 ,  178 , respectively, rotor plates  148 ,  174  experience wear, becoming slightly rounded on the underside adjacent and downstream from where vanes  152 ,  180  attach. This is evidence that the material is entrained in a Coanda flow that closely follows the contour of the periphery of each rotor. The leading side of each rotor vane  152 ,  180 , particularly in the region close to its respective rotor plate  148 ,  174 , also shows increasing wear with proximity to its outer edge. There is also a tendency for material to ride up the side of the vane as the material is moved radially outward by the vane. However, the wear pattern shows little scoring or pitting, which would be expected if the material was not entrained in a Coanda flow. These are the only areas of rotors at which wear has been noticed. Sides  40  and orifice plates  128 ,  130 ,  132 ,  134 ,  136  show some evidence of some large particle impacts, but no wearing pattern as observed on the rotors. It is expected that a softer material, such as pyrolytic carbon char particles, will experience even fewer collisions with parts of the RD mill  10 . 
     To enhance the Coanda effect on the material flowing past vanes  152  and  180  and around rotor plates  148 ,  174 , outer edges of the vanes can be beveled and aligned with the peripheral edge of the respective rotor plate  150  and  174 . The leading edge of each vane  152 ,  180  should go at least to the respective apex  150 ,  178  of the respective rotor plate  148 ,  174 . Positioning vanes  152 ,  180  such that their outer edges are on the trailing side of apical corners  150 ,  178  should reduce the amount of wear. 
     Rapid pressure changes, such as shock waves, may be generated each time the flowing material experiences a rapid acceleration, such as when the direction of flow rapidly changes, or experiences a pressure change. Such shock waves may generate large voltages due to the piezoelectric properties of the materials, as they experience rapid compression or decompression. Some places where large accelerations may take place include at discharge opening  166  of feed chute  78 , going around vanes  152 ,  180 , going around distributor rotor plate  148  and around rotor plate peripheral edges  176 , and going around rims  188  of orifices  138 ,  140 ,  142 ,  144 ,  146 . Large pressure changes may take place when the flow passes through an orifice or when the flow is pumped by a rotor. 
     A non-uniform electromagnetic field may also be generated within housing  12  as rotor assembly  38  rotates. Rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100 , as well as housing  12  and orifice plates  128 ,  130 ,  132 ,  134 ,  136 , are all made of low-carbon steel, which is ferromagnetic. The spinning rotors would create a rapidly changing, non-uniform electromagnetic field. These electromagnetic fields could enhance piezoelectric effects in the material in the Coanda flow. 
     Primary pulsed standing shock waves may also be produced as vanes  152 ,  180  on rotors  90 ,  92 ,  94 ,  96 ,  98 ,  100  alternately pass sides  40  and corners  42  of housing. Decompression would occur as the rotors pass each empty interior corner  42  of housing  12 , and compression would occur as the vanes pass the center of each side  40 . A shock wave of this type would be created every 40 degrees of rotation of a vane. 
     Moreover, secondary pulsed standing shock waves may be produced as vanes  152 ,  180  pass by support pins  190 , three of which are located proximate each rotor. Vanes  180  of the largest rotors, rotors  96 ,  98 ,  100 , pass within about 0.1 inches of support pins  190 . These shock waves would be produced every 120 degrees of rotation of a vane on a rotor due to compression of the flow as the vane passes each of the three support pins located near the rotor. Twenty-seven shock waves are generated for each rotation of a nonagon-shaped rotor. Thus, support pins  190  are employed to support the orifice plates and also to help generate shock waves. While in the described embodiment cylindrical support pins are employed for these purposes, a different arrangement can be used to support the orifice plates, and differently shaped members can be positioned in corners  42  opposite respective rotor vanes  150 ,  180  for generating the secondary shock waves. 
     Before material is fed into RD mill, rotor assembly  38  is brought up to an operating speed of rotation. The spinning rotors generate a large air flow with negative back pressure through feed tube  78  and down through RD mill  10 . Thus, any material fed into feed tube  78  will be immediately drawn in and accelerated rapidly towards distributor rotor  90 . 
     As noted above, material may be broken apart while accelerating down feed chute  78 , or while changing direction when exiting discharge opening  166 . It is believed that discharge opening  166  acts as an orifice through which air and the feed-stock material flows into the larger-volume region between top plate  44  and distributor rotor  90 . The flow through this first orifice provided by discharge opening  166  can cause a pressure change, which may be accompanied by a temperature change. The pressure change, along with the rapid acceleration of the particles exiting feed tube  78 , can cause a first shock compression and/or expansion and an initial breaking apart of some particles. 
     Small particles, less than about 1-1.5 inches (2.5-3.8 cm) in size, are quickly entrained in the Coanda flow and flow through distributor rotor  90  between distributor rotor plate  148  and distributor ring  164 . Distributor rotor  90  has five apical corners, rather than nine, to create longer wavelength shock waves, which has been found to be effective for breaking up larger particles. For this reason, in other embodiments that may be used for breaking up very hard materials, rotors  92 ,  94 ,  96 ,  98  and  100  may be configured with a generally increasing number of sides with increasing distance from a top end of housing  12  through which material is introduced. For example, distributor rotor  90  and rotor  92  could be configured as pentagons, rotors  94  and  96  as heptagons, and rotors  98  and  100  as nonagons. 
     When the Coanda flow passes through orifice  138 , the particles experience a rapid directional change and an increase in velocity with a corresponding pressure rise. The flow is immediately compressed because the volume between orifice plate  128  and rotor  92  is smaller than the volume between rotor  90  and orifice plate  128 . This can also cause a rapid increase in pressure and an accompanying temperature increase. At this stage, there would still be some high-velocity impacts of larger particles against sides  40  and against pins  190 , the larger particles bouncing off these structures or breaking up and then colliding with particles in the Coanda flow. 
     This process of rapid acceleration, expansion, and compression is repeated as the flow passes through each succeeding stage and rounds the rotors and orifices. These rapid variations in pressure and acceleration of the flowing material may contribute to creating shock waves which pulverize material flowing through RD mill  10 . In addition, the rapid compressing and decompressing of material in the flow can cause a build-up of piezoelectric energy and subsequent releases in the material, which may cause the break-up of some material into smaller sized particles. It is believed that the primary and secondary pulsed shock wave fronts are reinforced by shock waves created by piezoelectric energy releases in the flow. The rapid flow of material through the non-uniform electric and magnetic fields within RD mill  10 , which are generated by the spinning rotors, may also contribute to piezoelectric compression and decompression of material in the flow, thus also contributing to generating shock waves in the flowing material. 
     RD mill  10  can heat material being pulverized such that virtually all free moisture is driven off. Product comes out of RD mill  10  warmed to approximately 40-100 degrees Celsius or higher. Electric discharges from the material and the rapid expansion then compression after the flow passes through each orifice may increase the temperature of the flowing material and drive moisture out. It appears that volatile organic materials are also vaporized out of the flowing material or otherwise transformed. The piezoelectric energy releases and frictional heating of particles in the flow likely contribute to the observed general increase in temperature of the pulverized material. However, flowing only air or another gas, such as carbon dioxide, through RD mill  10  caused housing  12  to warm substantially. Therefore, some of the heating effect is also probably due to pressure changes in the flowing material and energy dissipated from shock waves. 
     In alternative embodiments, a gas other than air can be used for flowing the material being processed through RD mill  10 . For example, a non-reactive gas may be used instead of air, or a more reactive gas may be used. In other embodiments, a less reactive gas or a more reactive gas may be added to the airflow. Also, a cooling fluid, such as liquid or gaseous cold nitrogen can be added to the flowing gas to moderate the temperature of material being processed. 
     In the following examples certain procedures were carried out in processing material in RD mill  10 . First, RD mill  10  was brought up to a desired steady state operating speed of rotation. Then, the material to be processed was continuously fed into the feed chute with the RD mill  10  maintaining a steady state operational speed of rotation. If desired, the rotation speed was adjusted. For many materials, a small change in the rotation speed would significantly change in the power consumption of RD mill  10 . In fact, power consumption sometimes went down for an increase in rotational speed, indicating resonant operation. Typically, only material processed during steady state operating conditions was characterized. Material processed at the beginning and end of a run were usually not considered indicative of optimum operation. Processed material can be passed through RD mill  10  multiple times if desired. 
     Ultra-fine Carbon Particles 
     An example of a useful material that can be micronized by RD mill  10  is carbon. RD mill  10  can produce ultra-fine carbon particles from different carbon sources. Some of the starting materials that we have tested are pelleted standard reference carbon black N660, from Ballentine Enterprises Inc. of Borger, Tex., and dry carbon char having low volatiles produced by pyrolysis. With both materials, RD mill  10  produced a finer size micronized carbon material. 
     Granules of pyrolytic dry char having low volatiles were processed by Pulsewave, Inc. of Englewood, Colo. in a RD mill  10  produced by C. A. Arnold &amp; Associates, Inc., also of Englewood Colo. The carbon char was provided by Carbon Products International of Abington, Md. Carbon char will typically have about 7-8% oxygen content by weight, and also small amounts of other impurities, notably silica. RD mill  10  can process about one ton of such carbon per hour. The char can be processed at rotation speeds of about 3200-5700 rpm to produce a form of carbon black. Passing the granules through RD mill  10  operating at 3600 rpm one to two times was sufficient to convert the granules into a flowable powder of carbon black. When viewed under a light microscope the carbon black is seen appear as spherical particles mostly in the range of 0.5-1.5 micrometers. While appearing roughly spherical under a light microscope, they are in fact irregular in shape. When observed using an electron microscope (FIGS.  13 A and  13 B), the individual particles appear to be aggregates that include a variable number of about 100 or more aggregated or linked “primary” particles. The aggregates are rather similar in appearance to carbon black particles produced from controlled low-oxygen burning of organic gases and petroleum products. The overall appearance of the aggregates of adhered primary particles is somewhat like grape clusters. Most of the primary particles are quite uniform in size, ranging in size from about 10-30 nanometers. It is clear that the adhering primary particles consist of many atoms of carbon. It is possible that the primary particles can be released from the aggregated larger cluster particles by stronger resonance forces than applied in this example. 
     Carbon char was also processed using RD mill  10  operating at a speed of 4500 rpm. The resultant carbon powder was recycled through the RD mill  10  two additional times. The size distribution of this material as determined by direct microscopic measurement of hundreds of particles dispersed in water or isopropyl alcohol was mostly in the range of about 0.3-10 micrometers, with over half the particles below about one micrometer. Dispersion was best in water. As with the above example of carbon char processed at 3600 rpm, electron microscopy resolved the individual particles, as viewed by light microscopy, to be aggregates of generally spherical primary particle units assembled to form an irregular crystalline complex. 
     Similarly, about 50 kg of dry, pelleted standard reference carbon black N660, from Balentine Enterprises, Inc. of Borger, Tex., was processed by RD mill  10  operating at 4500 rpm. Carbon black is typically a higher purity form of carbon than is char. 
     To characterize the product of RD mill  10 , particle size distributions were determined, in part, using laser diffraction. This was carried out by Materials Analysis Laboratory of Micrometrics Instrument Co., of Norcross Ga. 2% by weight carbon samples were prepared in both isopropanol and deionized water containing 0.1% LOMAR® P-62 and were briefly ultrasonically treated. Scanning tunneling microscopy (STM) was performed at room temperature on compressed, sliced samples of carbon powder using a Nanoscope IIIA instrument with a 2082A probe head. All STM work was done at Laboratoire de Chimie Physique, ENSCMu, Mulhouse, France. Nitrogen surface area (NSA), multipoint (NSA) and statistical thickness surface area (STSA) were measured by the Materials Analysis Laboratory of Micrometrics Instrument Co. The n-dibutyl phthalate absorption number (DBPA) and the n-dibutyl phthalate absorption number, compressed sample (CDBPA) were measured by Titan Specialties, Pampa, Tex. 
     The analytic results characterizing the carbon black and the pyrolytic char before undergoing resonance disintegration, after being processed once by RD mill  10 , and after twice being processed by RD mill  10  are summarized in Tables 1 and 2, respectively. FIGS. 14 and 15 show the volume frequency vs. diameter for the carbon black samples dispersed in water and in isopropanol, respectively, and FIGS. 16 and 17 show the volume frequency vs. diameter for the pyrolytic char samples dispersed in water and in isopropanol, respectively. 
     For the standard reference carbon black N660 dispersed in water, resonance disintegration produced a significant decrease in the size of agglomerates. Prior to RD processing, approximately 60% of the material had a particle size distribution that was centered at 4.2 μm. After RD processing this peak is gone and about 90% of the carbon black was below 1 μm in particle diameter. 
     However, the carbon black samples dispersed in isopropanol exhibited different results. After RD processing, there was an increase in agglomerates. From what was essentially a single peak as 2.0 μm with only 1.1% above 5 μm, RD processing produced a trimodal distribution of particle sizes with 28% of the material above 5 μm. 
     
       
         
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Resonance Disintegration of Standard Reference Carbon Black N660 
               
             
          
           
               
                   
                   
                   
                   
                 Median 
                   
                   
               
               
                   
                   
                 Particle 
                   
                 Volume 
               
               
                   
                 Dispersion 
                 Diameter 
                 Significant 
                 Distribution 
                 % Volume 
                 % Volume 
               
               
                   
                 Solvent 
                 Range (μm) 
                 Peaks (μm) 
                 (μm) 
                 &lt;1 μm 
                 &gt;5 μm 
               
               
                   
                   
               
             
          
           
               
                 Before RD 
                 Water 
                 0.18-11 
                 0.42, 4.2 
                 3.0 
                 27 
                 21 
               
               
                   
                 Isopropanol 
                 0.28-22 
                 0.47, 2.0 
                 1.8 
                 12 
                 1.1 
               
               
                 After RD 
                 Water 
                  0.19-3.3 
                 0.47 
                 0.52 
                 90 
                 0 
               
               
                   
                 Isopropanol 
                 0.25-84 
                 0.53, 2.5, 20 
                 2.7 
                 12 
                 28 
               
               
                   
               
             
          
         
       
     
     
       
         
               
             
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Resonance Disintegration of Pyrolytic Carbon Char 
               
             
          
           
               
                   
                 Particle 
                   
                 Median 
                   
               
               
                   
                 Diameter 
                   
                 Volume 
                 % Volume 
               
             
          
           
               
                   
                 Dispersion 
                 Range 
                 Significant 
                 Distribution 
                 &lt;1 
                 &gt;5 
                 &gt;30 
               
               
                   
                 Solvent 
                 (μm) 
                 Peaks (μm) 
                 (μm) 
                 μm 
                 μm 
                 μm 
               
               
                   
                   
               
             
          
           
               
                 Before RD 
                 Water 
                 0.42-530 
                 75, 236 
                 61 
                 1.7 
                 95 
                 74 
               
               
                   
                 Isopropanol 
                 0.53-376 
                 1.5, 35 
                 17 
                 5.0 
                 67 
                 37 
               
               
                 After RD 
                 Water 
                 0.10-28  
                 0.33, 1.28, 5.6 
                 0.88 
                 51 
                 25 
                 0 
               
               
                   
                 Isopropanol 
                 0.45-28  
                 0.67, 1.5, 9.4 
                 1.6 
                 16 
                 10 
                 0 
               
               
                 After RD 
                 Water 
                 0.10-28  
                 0.42, 5.6 
                 0.52 
                 46 
                 25 
                 0 
               
               
                 Twice 
                 Isopropanol 
                 0.36-71  
                 2.1, 10.5 
                 2.7 
                 5.3 
                 39 
                 7 
               
               
                   
               
             
          
         
       
     
     The size of pyrolytic char particles dispersed in water was significantly reduced after resonance disintegration. Three fourths of the volume of unprocessed char was above 30 μm and less than 2% of the volume was submicron in particle size. RD processing eliminated essentially all particles above 30 μm and increased the submicron size volume fraction to about one half the material. A second RD processing did not significantly change the particle size distribution. 
     For char particles dispersed in isopropanol, a first RD processing reduced the largest particle size from over 350 μm to under 30 μm. It increased the volume of material from 0.4 to 5 μm, at the expense of 82% of the material over 5 μm. A second RD processing of the once processed material reduced the amount of material below 5 μm by over 32% and extended the range of the largest particles from 28 to 71 μm. 
     The RD processed char was also examined using an atomic force microscope. There were particles that clearly could be characterized as aggregates. However, about 90% of the free particles (non-aggregated particles) were below about 1 micron in size. 
     Table 3 shows measurements of various physical properties of pyrolytic char that has been RD processed. The physical properties of char did not vary significantly (&lt;10%) if the char was processed once or twice by resonance disintegration. The nitrogen surface area rose from 58 m 2 /g to 66 m 2 /g (+14%) as char was processed. 
     
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Physical Properties of Resonance 
               
               
                 Disintegrated Pyrolytic Carbon Char 
               
             
          
           
               
                 Nitrogen 
                 Statistical 
                   
                 n-dibutyl Phthalate 
               
               
                 Surface Area, 
                 Thickness 
                 n-Dibutyl Phthalate 
                 Absorption Number, 
               
               
                 Midpoint 
                 Surface Area 
                 Absorption Number 
                 Compressed Sample 
               
               
                   
               
               
                 66 m 2 /g 
                 50 m 2 /g 
                 79 ml/100 g 
                 72 ml/100 g 
               
               
                   
               
             
          
         
       
     
     Resonance disintegration causes a significant size reduction in standard carbon black N660 and in pyrolytic carbon char as observed when the materials are dispersed in water. De-agglomeration is particularly marked with the carbon black N660, where the submicron particle diameter population rises from 27% to about 90% of the volume after RD processing. Pyrolytic char granules are broken down and approximately 50% of the resulting carbon material is distributed in particle sizes of less than one micron. The remaining carbon, all less than 30 μm in size, is presumed to be composed of agglomerates that either are not decomposed by RD, even on further processing, or that form in equilibrium with more disagglomerated carbon particles under the conditions of dispersion. 
     Dispersions of the same RD processed carbon powders in isopropanol exhibit particle size distributions and size trends very different from the behavior of those powders in water. Regardless of whether the RD processed carbon particles originally were in the form of pyrolytic char or carbon black, the submicron fraction remains insignificant. As shown in FIGS. 14 and 16, most of the RD processed carbon is in a 1-3 μm range when dispersed in isopropanol. In addition, there is an increase in what are presumed to be aggolomerates above 5 μm on a single RD processing of the carbon black and on successive RD processing of char. 
     A possible explanation lies in the different chemistries of the two solvents. Water is more of a proton donor than acceptor. Isopropanol is both a strong proton donor and acceptor, and provides hydrophobic regions. Based on the greater tendency of the RD processed carbon to disperse in water over isopropanol, this indicates that RD processing makes the carbon surfaces more hydrophilic. 
     We measured the surface chemistry of the carbon, both before and after RD processing, with x-ray photoelectron spectroscopy. In the unprocessed carbon char, the total weight percentage of oxygen is about 7-8%. This is unchanged by RD processing. However, x-ray photoelectron spectroscopic analysis showed that the positioning of oxygen to the surface was increased by RD processing. Apparently, oxygen that was bound within the unprocessed pyrolytic char migrated to the surface of the processed material. The oxygen is hydrophilic, and therefore it is consistent with processed carbon particles being more readily dispersed in water than in isopropanol. Moreover, the additional surface oxygen reduces the number of sites that normally would be available to the isopropanol, thereby reducing the dispersion of the processed material in that solvent. This is all consistent with the data. 
     There are impurities other than oxygen in the char produced from scrap tires, such as zinc, sulfur, and silica particles. The zinc and sulfur can render the char undesirable for use as a feed stock material for the manufacture of rubber or other carbon-based products because they can be reactive. Large silica particles are undesirable for uses in ink jet printers where they can clog very small passages in the printing equipment. 
     When processed with RD mill, the silica particles are reduced to generally sub-micron sizes that generally will not clog ink jet printing equipment. However, a small amount of some larger silica particles can remain. It is believed that further processing with RD mill  10  or other processing may eliminate these larger particles to an acceptable level so that the RD processed char can be used for ink jet printing. 
     X-ray photo electron spectroscopy surface analysis of RD processed char shows that the other impurities, such as zinc and sulfur, are not exhibited on the surfaces of the elemental carbon particles. This indicates that these impurities are either bound within such carbon particles or they are free stand-alone particles. The impurities are non-reactive when bound within the carbon particles. As such, RD processed char can be a suitable feed stock material for manufacturing rubber and other carbon based products. 
     We have observed changes in RD processed carbon when the RD mill  10  has not been thoroughly cleaned after processing other materials. In one run, the carbon black particles readily captured (adsorbed) organic compounds that were volatilized during operation of the RD mill  10 . This adsorption increased the cohesive flow characteristics of the carbon black. The source of the organic molecules was found to be a small amount of residue that had remained in the machine from previous operations in which flax seeds had been processed. This residue (mostly oils) had not been removed by standard steps typically used to clean the RD mill  10 . The surfaces of the carbon particles were coated to the point where they could not absorb any n-dibutyl phthalate. It is believed that the coating in this example was monomolecular. Thus, RD mill  10  can be used to create desired coatings on carbon particles by adding a small amount of the desired coating material when processing carbon particles or during reprocessing of RD-processed carbon. It is apparent that carbon black can be readily and conveniently “coated” with many, and perhaps all, molecules for which it has affinity during passage through the RD mill  10 . 
     Crystals of Organic Molecules Containing Minerals 
     1. Magnesium citrate. Magnesium citrate is a water soluble mineral that can be used as a dietary supplement for humans and animals. Dry crystal granules of magnesium citrate (C 12 H 10 Mg 3 O 14 , molecular weight 451) comprised of about 16% magnesium were processed in RD mill  10 . The dry crystal granules were about +40 mesh (&gt;400 micron) in size before processing. The RD mill  10  was operated at 3200 rpm and yielded a fine, non-gritty powder. After processing, the resulting powder was suspended in ethanol and spread onto microscope slides. Individual crystals were selected for measurement against a micrometer scale. Individual crystals were mostly in the size range of about 1-4 microns. While some larger particles of about 10-20 microns were present; these were composed of aggregates of the smaller (1-4 micron) crystals. 
     2. Calcium citrate. Calcium citrate is also used as a dietary supplement as a source of calcium. Granular crystals of calcium citrate tetrahydrate (C 12 H 10 Ca 3 O 14 .4H 2 O) having an initial size range of about +40 mesh (&gt;400 micron) were processed by two passages through RD mill  10  at 4500 rpm. A very fine smooth powder was produced that when wetted became a slippery paste. The size of the powder crystals was mostly about 1-3 microns. The individual particles readily formed weak aggregates that could be disrupted when placed in ethanol and vigorously mixed in a blender to yield a dilute suspension. When mixed with various food stuffs (e.g., orange juice, yogurt, ice cream, puddings) the RD processed calcium citrate did not alter the smooth texture of these products. 
     3. Methylsulfonylmethane. Methylsulfonylmethane (CH 3 SO 2 CH 3 ) (MSM) is a naturally occuring sulfur containing organic compound that is used as a food supplement. MSM is also readily produced by a synthetic chemical process. The crystals of MSM are prone to adherence to one another, causing caking, and hard clumps typically form when MSM is stored. Clumps of MSM were processed in a RD mill  10  operated at 3000 rpm. This produced a fine powder that readily caked into soft clumps. The processed material had a particle size that was at least −270 mesh (&lt;53 micron) particle size. RD processed MSM dissolved more rapidly in water at room temperature than did crystals of MSM that were milled by grinding to 40-80 mesh. In test batches one gram of processed MSM was dissolved into 100 ml of water within about 15 seconds or less, whereas with the starting material clumps were still visible after two minutes of agitation. 
     Non-mineral Containing Organic Compounds 
     1. Creatine monohydrate. Creatine monohydrate (creatine) (C 4 H 9 N 3 O 2 )is abundant in muscle tissue, mostly in phosphorylated form. It serves as an energy reserve in muscle and is used as a nutritional supplement, particularly by athletes and body builders. Coarse, granular crystals of creatine having a particle size of about +60 mesh (&gt;300 microns) were manually fed into a RD mill  10  operating at about 3000 rpm. The particle size of the RD processed creatine was determined by passage through a series of screens. 93% of the processed creatine had a particle size of −400 mesh, and thus the particles were less than about 30 microns in their greatest dimension. It would be expected that even greater homogeneity could be achieved using a longer term continuous flow feed into RD mill  10 , as opposed to the manual delivery in this test. Under continuous, stable loading of RD mill  10  essentially 100% of the particles would predictably be −400 mesh size. In comparison with granular crystals of creatine, the RD mill processed creatine dissolved rapidly in water at room temperature. Saturated solutions were obtained within ten minutes compared with several hours using stock granulated crystals. 
     2. Ipriflavone. Ipriflavone is a water “insoluble” compound that is present in various plants, e.g. soybeans, and is also produced by chemical synthesis. It is considered effective for maintaining bone structure. 500 grams of white, translucent crystals of ipriflavone were processed by an RD mill  10  along with 20 kilograms of sodium chloride crystals used as a carrier to provide loading mass for the mill. The processed material had a particle size of about −270 mesh. The ipriflavone was recovered by flotation in water. Upon drying, the now caked ipriflavone was broken apart in a mortar and tested for speed of solution in methanol. While the starting material ipriflavone was only slightly soluble in methanol, the RD processed material dissolved about 20 times more rapidly than did the unprocessed crystals. This is consistent with increased surface area/mass in the processed material. These results predict that doses of orally administered ipriflavone, which is essentially insoluble in water, would be better assimilated by the body than the initial starting material. The ability to dissolve this material in various oils and alcohols should also be improved by fragmentation using RD. 
     3. Zein. Zein is a water insoluble protein used as a coating on tablets. Coarse, granular crystals of zein having a particle size of about +40 mesh (&gt;400 microns) were processed by passing the material twice through a RD mill  10  operating at about 3200 rpm. The resulting zein powder was examined microscopically and was found to consist of fine crystals with over 90% being in a size range of about 3-20 microns, with the smallest being about 1.5 microns and the largest being about 60 microns. The processed crystals appeared as flat sheets with a thickness much smaller than the length or width. The processed powder was dissolved in 80% ethanol-water by slowly adding it to the solvent while stirring rapidly. The processed zein powder dissolved to yield a relatively clear, light yellow solution. When put into 45% ethanol-water and mixed in a blender, the blender was coated almost immediately. 
     The foregoing description of various embodiments of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise embodiments disclosed. Numerous modifications or variations are possible in light of the above teachings. The embodiments discussed were chosen and described to illustrate the principles of the invention and demonstrate versatility in it&#39;s practical application, thereby enabling one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.