Abstract:
A high capacity magnetic filter separates diamagnetic and/or paramagnetic substances from fluid streams. Diamagnetic solid substances are magnetized under an external magnetic field through coordinated interaction of diamagnetic solid substances with an inducement paramagnetic material (IPM). The magnetic filter serves as a separation zone created by the presence of IPM and magnets that are shielded from the IPM by non-magnetic sleeves or partitions. The IPM in the void volume between the magnets affords large surface area onto which diamagnetic and paramagnetic materials can contact and be attracted to. The relative position and distance of the magnetic source, such a magnetic bar or electromagnet, to the solid mixture of diamagnetic and IPM are adjusted to induce sufficiently strong magnetism in the diamagnetic solids which causes the diamagnetic solids to be attracted by the magnetic field as well. Both diamagnetic and paramagnetic substances can be removed from a liquid or gas.

Description:
FIELD OF THE INVENTION 
     The present invention relates to robust, high capacity magnetic filters for removing paramagnetic and/or diamagnetic materials from gas and liquid streams. 
     BACKGROUND OF THE INVENTION 
     Paramagnetic substances can be magnetized under an external magnetic field. Paramagnetic materials include, for example, manganese, chromium, cerium, iron, cobalt, potassium, vanadium, and their oxides or sulfides. Without influence of the external magnetic field, the magnetic dipole in a paramagnetic molecule points in random directions, so it has zero magnetism. As a suitable external magnetic field is applied, a paramagnetic substance is magnetized since the number of magnetic dipoles aligned parallel toward the direction of the magnetic field is more than those aligned away from the field. 
     Conventional magnetic filters remove paramagnetic substances or particles from gas or liquid fluids through the influence of an external magnetic field generated by permanent magnetic or electromagnetic sources. For example, magnetic filters disclosed in U.S. Pat. No. 8,506,820 to Yen et al, U.S. Pat. No. 8,636,907 to Lin et al, and U.S. Pat. Nos. 8,900,449 and 9,080,112 both to Yen et al, can remove paramagnetic particles from liquid streams in refinery and chemical facilities. The paramagnetic particles which include FeS, FeO, Fe(OH) 2 , Fe(CN) 6 , etc. are formed when carbon steel, which is a common material in plant construction, corrodes in the presence of acidic contaminants in the process stream to yield ferrous ions, which react with sulfur, oxygen and water. These paramagnetic contaminants tend to adhere to magnets. 
     Diamagnetic substances contain pairs of magnetic dipoles which tend to cancel out the magnetism internally. Diamagnetic materials include, for example, carbon (diamond), carbon (graphite), silica, alumina, bismuth, phosphorous, mercury, zinc, lead, tin, copper, silver, gold, water, ethyl alcohol, etc. In the presence of an external magnetic field, the magnetic dipoles of diamagnetic substances align parallel and in reverse direction to the magnetic field and therefore exhibit no magnetism. Prior art magnetic filters cannot remove diamagnetic substances. 
     Filtration with mesh screens and the like is the standard employed to separate diamagnetic particles from gas or liquid fluids but this technique is not efficient for small particles. For example, nano carbon particles such as particulate matter PM 2.5 emitted from power plants, steel mills, and mobile sources including cars and motorcycles cannot be effectively abated. Similarly, nano particles in the form of catalyst fines, steel rust, carbon residue or polymerized slurry found in refinery and chemical plants cannot be effectively filtered. Solid particles comprising FeS, FeO, sand, carbon residue, etc. of various sizes are also present in natural gas processes. Paramagnetic and diamagnetic materials are major constituents of both natural and industrial pollutants and contaminants. 
     It is highly desirable to develop systems for removing both of paramagnetic and diamagnetic particles, or at least the diamagnetic particles, of all sizes from the gas and liquid fluids. 
     SUMMARY OF THE INVENTION 
     The present invention is based in part on the demonstration that common diamagnetic solid substances can be magnetized under an external magnetic field through coordinated interaction of the diamagnetic solid substances with an inducing or inducement paramagnetic material (IPM). The IPM which is solid should preferably not be in direct contact with the magnet which generates the external magnetic field. On the other hand, the diamagnetic solid substance preferably is in direct contact with the IPM or is uniformly mixed with the IPM. The position and distance of a magnetic source, such a magnetic bar or electromagnet, to the solid mixture of diamagnetic and IPM are adjusted and maintained so as induce sufficiently strong magnetism in the diamagnetic solids which causes the diamagnetic solids to be attracted by the magnetic field as well. In this fashion, both diamagnetic and paramagnetic substances can be removed from a liquid or gaseous stream in which the solid mixture is entrained or fluidized. Not all paramagnetic substances can induce magnetism in diamagnetic solid substances in the presence of an external magnetic field in the magnetic filters of the present invention. Thus, “inducement paramagnetic material” or “IPM” refers to solid paramagnetic material that can cause diamagnetic solid materials to exhibit sufficient magnetism to be attracted by a magnetic field and be removed or captured with the magnetic filter of the present invention. 
     Accordingly, in one aspect, the invention is directed to a method of removing diamagnetic material from a carrier stream that includes the steps of:
         contacting a carrier stream comprising a carrier fluid and a diamagnetic material to an inducement paramagnetic material within a region; and   establishing a magnetic field within the region thereby rendering the diamagnetic material sufficiently magnetic so as to be attracted by a magnet to a yield a cleaned carrier fluid with reduced levels of the diamagnetic material.       

     In another aspect, the invention is directed to a magnetic filter for separating diamagnetic contaminants from a carrier stream that includes: 
     a housing having (i) a stream inlet, (ii) a stream outlet and (iii) an interior region between the inlet and outlet; 
     inducement paramagnetic material (IPM) distributed within the interior region wherein the IPM is configured to come into physical contact with the diamagnetic contaminants; and 
     a magnet disposed within the interior region to generate a magnetic field sufficient to render the IPM magnetic. 
     The magnetic filter serves as a robust separation zone created by the presence of IPM and magnets that are shielded from the IPM by non-magnetic partitions. Preferably, elongated magnet assemblies are employed to generate a uniform magnetic field in the separation zone. The elongated magnet assemblies can be arranged in parallel or traverse to the fluid flow within the filter. The IPM in the void volume or space between the magnets afford a large surface area onto which diamagnetic and paramagnetic materials in the fluid steam can contact and be attracted to. While the invention will be described using permanent magnets to establish the magnetic field, it is understood that electromagnets can be employed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  and  FIG. 1B  are elevational cross sectional and top views, respectively, of an embodiment of a magnetic filter with inducement paramagnetic material packing and removable, vertically oriented permanent magnetic bar assemblies, with  FIG. 1B  depicting the magnetic filter with the cover plate off and illustrating a limited number of sleeve holders and packing material; 
         FIG. 1C  is a cross sectional view of a permanent magnetic bar assembly; 
         FIG. 1D  is a cross sectional view of an alternative permanent magnetic bar assembly; 
         FIG. 1E  is a cross sectional view of a permanent magnetic bar assembly; 
         FIG. 2A  and  FIG. 2B  are elevational and side cross sectional views, respectively, of an embodiment of a magnetic filter with inducement paramagnetic material packing, removable, horizontally oriented permanent magnetic bar assemblies, with  FIG. 2B  depicting a limited number of sleeve holders and packing material; 
         FIG. 2C  is a cross sectional view of a permanent magnetic bar assembly; 
         FIGS. 3A and 3B  are photographic images of the magnet pole locations in the permanent magnetic bar assemblies; and 
         FIGS. 4A and 4B  are photographic images of the paramagnetic powders attracted to exterior surfaces of the associated sleeves of the permanent magnetic bar assemblies. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1A  depicts the schematic configuration of a vertical filter  2  that comprises a housing  4  having an inlet pipe  6  that can be coupled to a contaminated process stream through control valve  8 , an outlet pipe  10  from which a treated process stream exits through control valve  12 . Housing  4  defines an interior region  14 . Flow through drain pipe  49 , which is welded to the bottom of housing  4 , is regulated with control valve  48  which is normally closed during filtration operations but which is opened during clean-up service to discharge flush fluid from housing  4 . The size of the opening in drain pipe  49  is sufficient to accommodate large particles that accumulate in the filtration process. 
     A cover plate  20  is fastened by bolts  22  to an annular flange  24  that is welded to the outer perimeter along the top opening in housing  4 . A polymer gasket or other suitable sealing means may be inserted between cover plate  20  and flange  24  to insure a tight seal during the operation cycle. A top supporting plate  26 , which is fastened to the top rim of wire cage  28  around the perimeter by bolts  30 , facilitates the removal of the entire core assembly from filter housing  4  during the clean-up cycle. Both the top supporting plate  26  and the top rim of wire cage  28  are placed on a supporting ring  42  which is permanently connected to filter housing  4 . The weight of the core assembly causes top supporting plate  26  and the top rim of wire cage  28  to press tightly against supporting ring  42  to prevent the open end of each holder sleeve  32  and, thus magnetic bar assemblies  34 , from coming in contact with the process fluid during the filtration process. 
     The core assembly includes multiple, vertically oriented removable permanent magnetic bar assemblies  34  with each being fitted into an elongated diamagnetic sleeve holder  32 , IPM packing elements or substances  36  which fill up the space in between the sleeve holders  32  as the magnetic inducing media for solid diamagnetic substances in the process stream. Wire cage  28 , as a holder of IPM packing  36 , is preferably made of coarse wire of diamagnetic substances, such as stainless steel, with mesh size slightly smaller than the size of IPM packing substance  36  to prevent their loss to the process flow. 
     Preferably the IPM packing elements  36  are in layered arrangement with the largest ones on top and the smallest ones at the bottom. This gradient packing matrix configuration enables the magnetic filter to capture diamagnetic and paramagnetic substances of different sizes without causing significant pressure drops and throughput reductions. 
     The IPM is preferably formed of materials with high and positive mass susceptibility. Suitable IPM include, for example, Ce, CeO 2 , CsO 2 , Co, CoO, Ni, CuO, NiO, NiS, Fe, FeO, Fe 2 O 3 , FeS, Mn, Ni/γAl 2 O 3 , Cr 2 O 3 , Dy 2 O 3 , Gd 2 O 3 , Ti, V, V 2 O 3 , Pd, Pt, Rh, Rh 2 O 3 , KO 2 , and mixtures thereof with Co, CoO, Ni, Fe, FeO, Fe 2 O 3 , FeS, Ni/γAl 2 O 3 , Cr 2 O 3 , Dy 2 O 3 , and Gd 2 O 3  being particularly preferred. Preferred configurations of the IPM packing elements include but not limited to conventional random packing such as rings, saddles, chips, and wires, structure packings, and macro-pore catalyst supports, such as guard-bed materials used in a fixed-bed reactor. 
     It is critical to keep the distance between the adjacent vertically oriented magnetic bar assembles  34  sufficiently close so that the IPM substances, which are packed in the filter, can induce sufficient magnetism to attract the diamagnetic substances from the process stream. The distance, which is measured from exterior surfaces of adjacent sleeve holders  32 , should be from 0.1 to 5 cm and preferably from 0.1 to 2 cm. The magnetic flux intensity within the interior region  14  in magnetic filter  2  should be from 2,000 to 20,000 GS, and preferably from 2,000 to 10,000 GS, and most preferably from 6,000 to 10,000 GS. 
     Each sleeve holder  32 , which is highly permeable to magnetic fields, has a sealed bottom and an open top end which is preferably welded at its perimeter to the fitted hole at the top supporting plate  26 . This prevents the open end of each holder sleeve  32  and the associated magnetic bar assembly  34  from coming into direct contact with the process fluid during filtration. Top supporting plate  26  bears the weight of the plurality of permanent magnetic bar assemblies  34  with their associated holder sleeves  32 , the IPM packing substances  36 , and wire cage  28 . 
       FIG. 1B  depicts the top view showing the top supporting plate  26  with its fitted holes for the sleeve holder  32 , and the IPM packing substance  36  which fills up the space between the sleeve holders  32 . One of sleeve holders  32  has a permanent magnetic bar assembly inserted therein with casing  38  enclosing a magnet block  40 . Casing  38  is permeable to magnetic fields. 
       FIG. 1C  depicts the vertical cross sectional view of a permanent magnetic bar assembly  34  that includes an elongated casing  38  that is preferably made of a diamagnetic metal such as stainless steel and defines a chamber that accommodates one or more encased magnet blocks  40 . Each magnetic bar assembly  34  has a pulling ring  44  for withdrawing it from sleeve holder  32 . A plurality of short magnet blocks or cylinders  40  are stacked one on top of another and arranged so that each of the two poles of one magnet block is juxtaposed to an opposite pole of an adjacent magnet block. In this staggered arrangement, the axis of each elongated magnet block  40  is perpendicular to the central axis along the length of assembly  34 . 
       FIG. 1D  illustrates a permanent magnetic bar assembly  110  where two adjacent pairs of blocks  102 , 104  having like poles pointing in the same first direction form a magnet block unit or array that is stacked over another magnet block unit, consisting of blocks  106 , 108  having like poles pointing in a second direction, which is opposite the first direction. The assembly  110  has a succession of such block units with opposite pole configurations. As is apparent, each magnet block unit or array can comprise more than 2 magnet blocks or cylinders. 
     In use, each permanent magnetic bar assembly  34  or  110  is supported within a sleeve holder  32 . It has been observed that the magnetic flux density of these encased permanent magnets as measured by a Tesla meter was essentially the same with or without a 304SSL sleeve. That is, the presence of the diamagnetic barrier (sleeve holder) did not result in a significant decay of the magnetic flux density. In contrast, permanent magnetic bar assemblies consisting of a plurality of magnet blocks that are arranged in tandem as shown in  FIG. 1E  exhibited a significant decrease in magnetic flux density when a 304SSL sleeve was used. 
     It has also been observed that diamagnetic and paramagnetic particles are not attracted to the entire surface of the magnetic bar assembly as shown in  FIG. 1E  but rather such particles form bands around the exterior surfaces. To reveal the arrangement of the magnet blocks in the magnetic bar assembly, Magnetic Viewer Cards were placed in front of both of the magnetic bar assemblies shown in  FIGS. 1C and 1E . The Magnetic Viewer Card is a flexible film containing liquid magnetic power.  FIGS. 3A and 3B  show images that are created through polar induction by the magnetic field of the magnets. The images of the magnetic poles in each assembly can be seen through the card, where the light areas represent the junctions where N and S poles meet and the locations are quantitatively measured. 
     To compare the performance of the preferred magnetic bar assembly of  FIG. 1C  to that of the magnetic bar assembly of  FIG. 1E , the same mass of Fe 2 O 3  powder was placed on separate pieces of paper (5.5 cm by 10 cm). Each assembly with its associated sleeve was slowly rotated in non-contact fashion over the powder at a distance of 0.5 to 1.0 cm until essentially all the powder was pick up by attraction. As shown in  FIG. 4A , almost the entire sleeve surface of the preferred magnetic bar assembly ( FIGS. 1C and 3A ) was covered with iron oxide powder. In contrast, as shown in  FIG. 4B , the magnetic bar assembly of  FIGS. 1E and 3B  was able to attract iron powder onto a limited surface area of the sleeve surface where like poles met. As is apparent, the effective area of attraction is larger with the preferred magnetic bar assembly where the longitudinal axis of each magnetic bar is perpendicular to the central axis or length of the magnetic bar assembly. 
     As shown in  FIG. 1A , a process stream entering filter housing  4  via line  6  initially travels through wire cage  28  and contacts the IPM packing substances while under the influence of a suitable magnetic field generated by the permanent magnetic bar assemblies  34 . Solid paramagnetic particles in the process stream  6  will be attracted to sleeve holders  32  and to the IPM packing substances  36 . Diamagnetic solids in the process stream  6  having magnetism induced by the IPM packing substances are also attracted to sleeve holder  32  and to IPM packing substances  36 . Treated process stream passes through wire cage  28  and exits filter housing  4  through control valve  12  and line  10 . 
     In the clean-up cycle, control valves  8  and  12  are closed in sequence. Cover plate  20  is opened and the entire core assembly, including permanent magnetic bar assemblies  34 , top supporting plate  26  along with sleeve holders  32 , wire cage  28  containing IPM packing substances  36 , is withdrawn from filter housing  4 . Thereafter, permanent magnetic bar assemblies  34  are withdrawn from the sleeve holders  32  to remove the magnetic field from the interior  14  thereby releasing the attracted solids of paramagnetic and diamagnetic substances from the outer surface of sleeve holders  32  and surfaces of the IPM packing. The core assembly is washed with water or other suitable fluid before the magnetic bar assemblies  34  are reinserted into sleeve holders  32 . The cleaned core assembly is then re-positioned into filter housing  4  and the top opening is closed and sealed with cover plate  20  and the fitted gasket. Before starting the operation cycle, control valves  46  and  48  are opened to briefly introduce high pressure fluid, such as water, process stream or air from line  47  to flush out the residual solids in filter housing  4 , and to remove the flushed solids through control valve  48  and drain line  49 . Finally, control valves  46  and  48  are closed and control valves  8  and  12  are opened to start the operation cycle again. 
       FIG. 2A  depicts a horizontal filter  50  that comprises a housing  52  having an inlet pipe  54  that can be coupled to a contaminated process stream through control valve  56 , an outlet pipe  58  from which a treated process stream exits through control valve  60 . Housing  52  defines an interior region  62 . Flow through drain pipe  64 , which is welded to the bottom of housing  52 , is regulated with control valve  66  which is normally closed during filtration operation and, is opened during clean-up service to discharge flush fluid from housing  52 . 
     The left cover plate  68  is fastened, by bolts  70  to an annular flange  72  that is welded to the outer perimeter along left side opening of housing  52 , while the right cover plate  74  is fastened, by bolts  76  to an annular flange  78  that is welded to the outer perimeter along right side opening of housing  52 . A polymer gasket may be inserted between cover plates and flanges. 
     The filter assembly includes horizontal multiple permanent magnetic bar assemblies  80  that are removable from filter housing  52 . Each bar assembly  80  fits into an elongated diamagnetic sleeve holder  82 , which is constructed of a diamagnetic metal such as stainless steel 304SSL. Each of the sleeve holders  82  is sealed at one end and the open end is preferably welded to the fitted hole in cover plate  68  to form integral units therewith. To secure the position and support the weight of sleeve holders  82  and the magnetic bar assembly  80 , each sleeve holder is fitted into a hole of the partition plate  88  which is welded to housing  52  to divide filter interior into two equal chambers. To induce the magnetism to solid diamagnetic substances in the process stream, wire cages  90  is filled with IPM packing substances  92  which are inserted into the space between the sleeve holders  82  from both sides of the filter openings. Wire cage  90 , as a holder of IPM packing substances  92 , is preferably made of coarse wire of diamagnetic substances with mesh size slightly smaller than the size of IPM packing substances  92  to prevent their loss to the process flow. 
     Preferred IPM packing substances and configurations are the same as those used in the vertically oriented magnetic filter  2  shown in  FIG. 1A . The spacing between the exterior surfaces of adjacent sleeves  82  holding horizontally oriented magnetic bar assemblies  80  should be in the range from 0.1 to 5 cm, and preferably from 0.1 to 2 cm. The magnetic flux intensity in the filter should be 2,000 to 20,000 GS, preferably 2,000 to 10,000 GS, and more preferably 6,000 to 10,000 GS. 
     As depicted in  FIGS. 2B and 2C , casing  100  of each permanent magnetic bar assembly  80  is a diamagnetic metal such as stainless steel 304 SSL and defines a chamber that accommodates one or more magnet blocks to form a permanent magnetic bar assembly  80 . Each permanent magnetic bar assembly  80  has a pulling ring  96  on top for withdrawing from sleeve holder  82  during clean-up cycle. A plurality of short magnet blocks  94  are stacked one on top of another and arranged so that each of the two poles of one magnet block is juxtaposed to an opposite pole of an adjacent magnet block. 
       FIG. 2B  depicts the cross sectional lateral side view showing the fitted holes for the sleeve holder  82 , and the IPM packing substance  92  which fills up the space between the sleeve holders. 
     The configuration of the magnetic filter  50  directs the process stream entering filter housing  52  via line  54  to flow downward in left chamber toward the bottom opening between partition plate  88  and filter housing  52 . The process stream then flows upward in right chamber toward the exit and treated process stream exits filter housing  52  through control valve  60  and line  58 . In both chambers of the filter, the process stream travels through the outer surfaces of sleeve holders  82 , and the wire cage  90  contacting the IPM packing substances  92  under influence of a strong magnetic field generated by the permanent magnetic bar assemblies  80 . Solid paramagnetic substances in the process stream  54  will be attracted to the outer surfaces of sleeve holders  82 , and to the surfaces of IPM packing substances  92 . Diamagnetic solids in the process stream  54  having magnetism induced by the IPM packing substances will be attracted to outer surfaces of sleeve holders  82  and to the surfaces of IPM packing substances  92 . 
     In the clean-up cycle, permanent magnetic bar assemblies  80  are withdrawn from the sleeve holders  82  from the filter to remove the magnetic field from interior space  62  of the filter, releasing the attracted solids of paramagnetic and diamagnetic substances from the outer surfaces of sleeve holders  82  and surfaces of the IPM packing  92 . After control valves  56  and  60  are closed, control valves  66  and  120  are opened to introduce high pressure fluid via line  122 , such as water, process stream or air to flush out the released solids through control valve  66  and drain line  64 . To start the operation cycle, magnetic bar assemblies  80  are replaced into sleeve holders  82 , control valves  66  and  120  are closed and control valves  60  and  56  are opened in sequence. 
     The magnetic filters of the present invention are particularly suited for abatement programs to remove airborne contaminants especially particles that are 0.1 nm to 1.0 mm in size, such as particulate matter PM 2.5. Both diamagnetic and paramagnetic particles can be removed from the streams. For example, filters can be installed in clean room operations or in airplanes to clean recirculated air, in electric power plant or steel mill to clean up flue gas, or in mobile emission sources, such as cars to reduce air pollution. The magnetic filters can also be employed to remove diamagnetic particles in liquid streams in refineries, chemical plants and other facilities in continuous operations where particles in process streams can accumulate and damage equipment. For instance, inorganic catalysts, that become free flowing or otherwise detached from a catalyst bed, can be effectively removed from streams with the inventive magnetic filter. Furthermore, this filter can be installed in ultra-pure water production facility to remove the ultra-fine diamagnetic and paramagnetic particles from the product stream. Similarly, a filter can be positioned upstream of a natural gas treatment plant to remove ultra-fine diamagnetic particles, such as sand, carbon residual, and diamagnetic metal oxides, and ultra-fine paramagnetic particles, such iron sulfide, iron oxides, etc., from a natural gas stream at the gas field in order to protect plant equipment and improve plant efficiency. 
     EXAMPLES 
     The following examples are presented to further illustrate different aspects and embodiments of the invention and are not to be considered as limiting the scope of the invention. To demonstrate the interaction between paramagnetic and diamagnetic substances under the influence of an external magnetic field generated by permanent magnets, paramagnetic and diamagnetic powders were selected for various experiments. The substances are classified into paramagnetic and diamagnetic based on their mass susceptibilities (MS). 
     Mass susceptibility is the magnetic susceptibility of a substance per gram and magnetic susceptibility is the magnetization of a material per unit applied field. It describes the magnetic response of a substance to an applied magnetic field. All substances are characterized by mass susceptibility (MS) values. Paramagnetic substances have higher and positive MS values whereas diamagnetic substances have lower or negative MS values. Table 1 lists the MS values of selected substances. 
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Mass Susceptibility of Substances 
               
             
          
           
               
                   
                   
                 Mass Susceptibility  
               
               
                   
                 Substance 
                 (10 −6  c.g.s. units) 
               
               
                   
                   
               
             
          
           
               
                   
                 Aluminum oxide (Al 2 O 3 ) 
                 −37.0 
               
               
                   
                 Carbon, diamond (C) 
                 −5.9 
               
               
                   
                 Carbon, graphite (C) 
                 −6.0 
               
               
                   
                 Cerium 
                 +5,160 
               
               
                   
                 Cesium oxide (CsO 2 ) 
                 +1,534 
               
               
                   
                 Chromium (Cr) 
                 +180 
               
               
                   
                 Chromium oxide Cr 2 O 3 ) 
                 +1,960 
               
               
                   
                 Cobalt (Co) 
                 +4,900 
               
               
                   
                 Cobalt oxide (CoO) 
                 +4,900 
               
               
                   
                 Cupper oxide (CuO) 
                 +260 
               
               
                   
                 Dysprosium oxide (Dy 2 O 3 ) 
                 +89,600 
               
               
                   
                 Gadolinium oxide (Gd 2 O 3 ) 
                 +53,200 
               
               
                   
                 Iron (Fe); Iron oxide (FeO) 
                 +7,200 
               
               
                   
                 Iron oxide (red) (Fe 2 O 3 ) 
                 +3,586 
               
               
                   
                 Iron sulfide (FeS) 
                 +1,074 
               
               
                   
                 Iron Sulfate (FeSO 4 ) 
                 +12,400 
               
               
                   
                 Iron Chloride (FeCl 3 ) 
                 +13,450 
               
               
                   
                 Manganese (Mn-alpha) 
                 +529 
               
               
                   
                 Manganese (Mn-beta) 
                 +483 
               
               
                   
                 Nickel (Ni); Nickel oxide (NiO) 
                 +660 
               
               
                   
                 Nickel sulfide (NiS) 
                 +190 
               
               
                   
                 Potassium oxide (KO 2 ) 
                 +3,230 
               
               
                   
                 Palladium (Pd) 
                 +567 
               
               
                   
                 Platinum (Pt) 
                 +202 
               
               
                   
                 Rhodium (Rh) 
                 +110-123 
               
               
                   
                 Rhodium oxide (Rh 2 O 3 ) 
                 +104 
               
               
                   
                 Silicon (Si) 
                 −3.9 
               
               
                   
                 Silicon carbide (SiC) 
                 −12.8 
               
               
                   
                 Silicon oxide (SiO 2 ) 
                 −29.6 
               
               
                   
                 Titanium (Ti) 
                 +150-153 
               
               
                   
                 Titanium oxide (TiO 2 ) 
                 +5.9 
               
               
                   
                 Vanadium (V) 
                 +255 
               
               
                   
                 Vanadium oxide (V 2 O 3 ) 
                 +1,976.0 
               
               
                   
                 Water (H 2 O) 
                 −7.2 
               
               
                   
                 Zinc (Zn) 
                 −11.4 
               
               
                   
                 Zinc oxide (ZnO) 
                 −46.0 
               
               
                   
                   
               
             
          
         
       
     
     Example 1 
     The degree or strength of magnetism exhibited by selected solid substances with high MS values in a magnetic field was measured. A permanent magnetic bar assembly with a magnetic strength of 6,000 GS was employed. The selected solid powders were: cobalt (Co), iron (Fe), nickel (Ni), nickel oxide (NiO), iron oxides (FeO and Fe 2 O 3 ), iron sulfate (FeSO 4 ), iron chloride (FeCl 3 ), Ni supported on γ-alumina catalyst (Ni/γAl 2 O 3 ), dysprosium oxide (Dy 2 O 3 ), gadolinium oxide (Gd 2 O 3 ), and chromium oxide (Cr 2 O 3 ). 
     For each test, approximately 0.5 grams of powder were weighed by a precision balance (to 10 −4  grams) and placed into a (precision weighed) glass vessel. The permanent magnetic bar assembly was then placed near the powder. After attracting of the power, the magnetic bar was removed and the vessel with residual powders (if any) was weighed. Weight percent (%) of the powders attracted by magnetic bar was calculated. 
     As shown in the data set forth in Table 2, metals and their oxides with MS values of approximately 600 to 7,000×10 −6  c.g.s. unit are readily attracted by the permanent magnetic bar assembly, except for NiO (no attraction) and Cr 2 O 3  (only 82%). As expected, Dy 2 O 3  and Gd 2 O 3  with their very high susceptibilities showed complete attraction. Surprisingly, however, even with very high MS values (over +10,000×10 −6 ), iron sulfate (FeSO 4 ) and iron chloride (FeCl 3 ) showed no magnetism and were not attracted by the MB. This experiment suggests that mass susceptibility serves only a guideline for selecting suitable inducement paramagnetic materials. Metals or metal oxides are possible candidates as suitable inducing paramagnetic substances while metal salts such as FeSO 4  or FeCl 3  are excluded from the consideration, despite of their high MS values. 
     
       
         
               
               
             
               
               
               
               
               
               
             
               
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Permanent paramagnetic bar strength: 6000 GS 
                   
               
               
                 para-magnetic 
                   
               
             
          
           
               
                   
                   
                   
                 Vessel after 
                 Powder 
                 % Powder 
               
               
                   
                 Vessel 
                 Powder 
                 attraction 
                 attracted  
                 attracted by 
               
               
                   
                 (g) 
                 (g) 
                 (g) 
                 by MB (g) 
                 MB (g) 
               
               
                   
               
             
          
           
               
                 Co 
                 21.7539 
                 0.5001 
                 21.7555 
                 0.4985 
                 99.68 
               
               
                 Fe 
                 23.347  
                 0.5067 
                 23.347 
                 0.5067 
                 100.00 
               
               
                 Ni 
                 23.3185 
                 0.506  
                 23.3185 
                 0.5060 
                 100.00 
               
               
                 FeO 
                 23.2832 
                 0.5046 
                 23.2844 
                 0.5034 
                 99.76 
               
               
                 NiO 
                 22.9339 
                 0.5038 
                 23.4376 
                 0.0001 
                 0.02 
               
               
                 FeCl 3   
                   
                   
                   
                   
                 0.00 
               
               
                 FeSO 4   
                   
                   
                   
                   
                 0.00 
               
               
                 Fe 2 O 3   
                 21.3278  
                 0.5044 
                 21.3284 
                 0.5038 
                 99.88 
               
               
                 Ni/γAl 2 O 3   
                 21.3745 
                 0.5025 
                 21.3745 
                 0.5025 
                 100.00 
               
               
                 Dy 2 O 3   
                 21.7519  
                 0.5023 
                 21.7549 
                 0.4993 
                 99.40 
               
               
                 Cr 2 O 3   
                 23.2467  
                 0.5012 
                 23.3347 
                 0.4132 
                 82.44 
               
               
                 Gd 2 O 3   
                 23.3186  
                 0.5006 
                 23.3186 
                 0.5006 
                 100.00 
               
               
                   
               
             
          
         
       
     
     Example 2 
     This experiment confirmed that diamagnetic substances by themselves are not attracted to a magnetic bar. The diamagnetic substances tested were silicon, silicon carbide (SiC), γ-alumina (γAl 2 O 3 ), non-magnetic butadiene, titanium oxide (TiO 2 ), ceramic, activated carbon, polyethylene, and elemental sulfur. Magnetic butadiene was also tested. A permanent magnetic bar assembly with a magnetic strength of 6,000 GS was positioned next to powder samples; none of the powders was attracted onto the magnetic bar, except the magnetic butadiene (containing paramagnetic substance). The presence of the magnetic field did not induce magnetism in the diamagnetic materials. 
     Example 3 
     Simply coating a permanent magnetic bar assembly with a paramagnetic substance does not render the assembly attractive to diamagnetic materials. In this example, the permanent magnetic bar assembly coated with iron oxide (FeO) powder was positioned each of various diamagnetic powders that included Si, SiC, SiO 2 . Al 2 O 3 , non-magnetic butadiene, magnetic butadiene, TiO 2 , ceramics, activated carbon, and polyethylene. None of the diamagnetic powders was attracted by permanent magnetic bar assembly, except for the magnetic butadiene which contained a paramagnetic substance. 
     Example 4 
     In mixing a diamagnetic substance with a suitable IPM substance, the paramagnetic substance acts as a magnetic inducing agent. The diamagnetic substance in the mixture exhibits magnetism when the mixture is exposed to a magnetic field that is created by a permanent magnetic bar or electromagnetic. Both the paramagnetic and diamagnetic substances in the mixture are attracted to the magnet. 
     Experiments were performed in air (gas phase) at ambient conditions. For each test, approximately 1.0 gram of diamagnetic powders and 0.1 grams of paramagnetic powders were weighed by a precision balance (to 10 −4  grams) and the mixture was placed into a precision weighed glass vessel. A permanent magnetic bar assembly with magnetic power of 6,000 GS was position adjacent the mixture to attract powders from the vessel. The magnet was removed and the vessel with residual mixed powders was weighed. The weight percent (%) of the mixed powders attracted by the magnet; the data is summarized in Tables 3 and 4. 
     
       
         
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 3 
               
             
             
               
                   
               
               
                 Permanent paramagnetic bar strength: 6000 GS 
                   
               
               
                 Diamagnetic Material (DM):Ni/γAl 2 O 3    
                   
               
               
                 (PM powder) = 10:1 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Vessel 
                 DM + Ni/γ 
                   
               
               
                   
                   
                   
                 Ni/ 
                 after MB 
                 Al 2 O 3   
                 % 
               
               
                   
                 Vessel 
                 DM 
                 γAl2O3 
                 attraction 
                 attracted  
                 attracted 
               
               
                   
                 (g)  
                 (g) 
                 (g) 
                 (g) 
                 by MB (g) 
                 by MB 
               
               
                   
               
             
          
           
               
                 γ Al 2 O 3   
                 22.8674 
                 1.0048 
                 0.1024 
                 23.9014 
                 0.0732 
                  6.61 
               
               
                 Si 
                 23.2828 
                 1.0005 
                 0.1014 
                 23.3942 
                 0.9905 
                 89.89 
               
               
                 SiC 
                 22.9324 
                 1.0018 
                 0.1048 
                 23.9704 
                 0.0686 
                  6.20 
               
               
                 RFCC 
                 21.3282 
                 1.0013 
                 0.1028 
                 22.3216 
                 0.1107 
                 10.03 
               
               
                 S 
                 21.3285 
                 1.0027 
                 0.1009 
                 22.2885 
                 0.1436 
                 13.01 
               
               
                 Activated 
                 21.3604 
                 1.0008 
                 0.1008 
                 22.3683 
                 0.0937 
                  8.51 
               
               
                 Carbon 
               
               
                   
               
             
          
         
       
     
     As set forth in Table 3, with Ni/γAl 2 O 3  as the inducing agent, the magnetic bar showed only mild attractions for γ Al 2 O 3 , SiC, resid fluid cracking catalyst (RFCC-Al 2 O 3 /SiO 2 : 70/30), elemental sulfur (S), and activated carbon, but exhibited a significantly higher attraction for silicon. 
     
       
         
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 4 
               
             
             
               
                   
               
               
                 Permanent paramagnetic bar strength: 6000 GS 
                   
               
               
                 Diamagnetic Material:FeO (PM powder) = 10:1 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Vessel 
                 DM + 
                   
               
               
                   
                   
                   
                   
                 after MB 
                 FeO 
                 % 
               
               
                   
                 Vessel 
                 DM 
                 FeO 
                 attraction  
                 attracted 
                 attracted 
               
               
                   
                 (g) 
                 (g) 
                 (g) 
                 (g) 
                 by MB(g) 
                 by MB 
               
               
                   
               
               
                 γ Al 2 O 3   
                 21.7532  
                 1.0047 
                 0.102  
                 21.989  
                 0.8709 
                 78.69 
               
               
                 Si 
                 23.2471 
                 1.0032 
                 0.1034 
                 23.3912 
                 0.9625 
                 86.98 
               
               
                 SiC 
                 23.319  
                 1.0015 
                 0.1052 
                 23.4359 
                 0.9898 
                 89.44 
               
               
                 RFCC 
                 22.8697 
                 1.004  
                 0.1065 
                 22.955  
                 1.0252 
                 92.32 
               
               
                 S 
                 23.282  
                 1.0013 
                 0.1044 
                 23.4632 
                 0.9245 
                 83.61 
               
               
                 Activated 
                 23.2832 
                 1.0012 
                 0.1043 
                 23.3733 
                 1.0154 
                 91.85 
               
               
                 Carbon 
                   
                   
                   
                   
                   
                   
               
               
                   
               
             
          
         
       
     
     As set forth in table 4, FeO is a better inducing agent than Ni/γAl 2 O 3  since the magnetic bar attracted a much higher percentage of the paramagnetic and diamagnetic mixtures. 
     Example 5 
     This experiment is similar to that of Example 4 except that an IPM in the form of thin carbon steel wires (CSW) was used instead of iron powder. As shown in Table 5, 70 to nearly 100% of the diamagnetic substance were attracted by the magnet, except in the case the elemental sulfur. 
     
       
         
               
               
             
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 5 
               
             
             
               
                   
               
               
                 Permanent paramagnetic bar strength: 6000 GS 
                   
               
               
                 Diamagnetic Material (DM):Carbon Steel Wire (CSW)  
                   
               
               
                 (PM substance) = 10:5 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Vessel 
                 DM + 
                   
               
               
                   
                   
                   
                   
                 after MB 
                 CSW 
                 % 
               
               
                   
                 Vessel 
                 DM 
                 CSW 
                 attraction  
                 attracted 
                 attracted 
               
               
                   
                 (g) 
                 (g) 
                 (g) 
                 (g) 
                 by MB (g) 
                 by MB 
               
               
                   
               
             
          
           
               
                 γ Al 2 O 3   
                 21.7529 
                 1.0062 
                 0.5057 
                 22.203  
                 1.0618 
                 70.23 
               
               
                 Si 
                 23.2464 
                 1.0031 
                 0.5071 
                 23.2854 
                 1.4712 
                 97.42 
               
               
                 SiC 
                 23.3189 
                 1.0029 
                 0.5038 
                 23.4808 
                 1.3448 
                 89.25 
               
               
                 RFCC 
                 22.8686 
                 1.0064 
                 0.5035 
                 23.2035 
                 1.1750 
                 77.82 
               
               
                 S 
                 21.3598 
                 1.0012 
                 0.1023 
                 22.3472 
                 0.1161 
                 10.52 
               
               
                 Activated  
                 23.2827 
                 1.003  
                 0.5011 
                 23.6792 
                 1.1076 
                 73.64 
               
               
                 Carbon 
               
               
                   
               
             
          
         
       
     
     Example 6 
     Liquid phase testing was conducted at ambient conditions. Specifically, for each test, approximately 50 grams of water were mixed with 1.0 gram diamagnetic powder in a precision weighed vessel. Thereafter, paramagnetic powder was added into the mixture. A permanent magnetic bar assembly, with a magnetic power of 6,000 GS, was inserted into the liquid mixture, allowing the suspended solid powders to be attracted by the magnet. The magnet was removed and solid powders scrapped off and the cleaned magnet was reinserted into the solvent and allowed to attract additional powder. After removing the magnet the second time, the vessel with the solution containing the residual powders was weighed. The weight percent (%) of the mixed powders attracted by magnet was calculated. 
     Table 6 are the results for testing using water as the solvent, RFCC powder (equilibrium resid fluid cracking catalyst (SiO 2 /Al 2 O 3 : 7/3) as the diamagnetic material (DM), and Fe 2 O 3  as the IPM. Approximately 0.1, 0.3, 0.5, and 0.7 grams of Fe 2 O 3  were added in each instance and the results show that 60 to nearly 100% of the mixed powders was attracted by the magnet, depending upon the amount of Fe 2 O 3  added and the position of the magnet (related to magnetic strength). The amount of powder attracted was proportional to the amount of Fe 2 O 3  added to the mixture. 
     
       
         
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 6 
               
             
             
               
                   
               
               
                 Permanent Magnet Bar (MB) Strength: 6,000 GS 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Vessel/ 
                 DM +  
                   
               
               
                   
                   
                   
                   
                 Solution 
                 Fe 2 O 3   
                 % 
               
               
                   
                   
                   
                   
                 after 
                 attracted 
                 attracted 
               
               
                 Vessel  
                 Solution 
                 DM  
                 Fe 2 O 3   
                 attraction 
                 by 
                 by 
               
               
                 (g) 
                 (g) 
                 (g) 
                 (g) 
                 by MB (g) 
                 MB 
                 MB 
               
               
                   
               
             
          
           
               
                 Water:RFCC:Fe 2 O 3  = 50:1:0.1 
                   
               
             
          
           
               
                 12.0105 
                 50.0064 
                 1.0005 
                 0.1011 
                 62.1254 
                 0.9931 
                 90.15 
               
             
          
           
               
                 Water:RFCC:Fe 2 O 3  = 50:1:0.3 
                   
               
             
          
           
               
                 11.9915 
                 50.2518 
                 1.001 
                 0.3061 
                 62.3449 
                 1.2055 
                 92.23 
               
             
          
           
               
                 Water:RFCC:Fe 2 O 3  = 50:1:0.5 
                   
               
             
          
           
               
                 11.9744 
                 50.428 
                 1.0168 
                 0.5008 
                 62.5725 
                 1.3475 
                 88.79 
               
             
          
           
               
                 Water:RFCC:Fe 2 O 3  = 50:1:0.7 
                   
               
             
          
           
               
                 11.9824 
                 50.4629 
                 1.0381 
                 0.7024 
                 62.4704 
                 1.7154 
                 98.56 
               
               
                   
               
             
          
         
       
     
     Example 7 
     This experiment was similar to that of Example 6 except diesel was the solvent. The results as set forth in Table 7 demonstrate that approximately 39 to 92% of the mixed solid powders was attracted by the magnet with the amount of powder in diesel attracted by the magnet was proportional to the amount of Fe 2 O 3  added to the mixture with one exception. 
     
       
         
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
               
               
             
               
               
               
               
               
               
               
             
           
               
                 TABLE 7 
               
             
             
               
                   
               
               
                 Permanent Magnet Bar (MB) Strength: 6,000 GS 
                   
               
             
          
           
               
                   
                   
                   
                   
                 Vessel/ 
                 DM +  
                   
               
               
                   
                   
                   
                   
                 Solution 
                 Fe 2 O 3   
                   
               
               
                   
                   
                   
                   
                 after 
                 attracted 
                 %  
               
               
                 Vessel  
                 Solution 
                 DM 
                 Fe 2 O 3   
                 attraction 
                 by 
                 attracted 
               
               
                 (g) 
                 (g) 
                 (g) 
                 (g) 
                 by MB (g) 
                 MB 
                 by MB 
               
               
                   
               
             
          
           
               
                 Diesel:RFCC:Fe 2 O 3  = 50:1:0.1 
                   
               
             
          
           
               
                 11.9753 
                 50.1911 
                 1.0013 
                 0.1025 
                 62.6677 
                 0.6025 
                 54.58 
               
             
          
           
               
                 Diesel:RFCC:Fe 2 O 3  = 50:1:0.3 
                   
               
             
          
           
               
                 11.9917 
                 50.0825 
                 1.0047 
                 0.3017 
                 62.3252 
                 1.0554 
                 80.79 
               
             
          
           
               
                 Diesel:RFCC:Fe 2 O 3  = 50:1:0.5 
                   
               
             
          
           
               
                 11.9192 
                 50.0838 
                 1.0335 
                 0.5085 
                 62.4436 
                 1.1014 
                 71.43 
               
             
          
           
               
                 Diesel:RFCC:Fe 2 O 3  = 50:1:0.7 
                   
               
             
          
           
               
                 12.0006 
                 50.1219 
                 1.0009 
                 0.7034 
                 62.2536 
                 1.5732 
                 92.31 
               
               
                   
               
             
          
         
       
     
     Example 8 
     This experiment demonstrates that the magnetic strength of the 6000 GS permanent magnets employed in the above examples decreased exponentially (with 10 4  power) with distance from a magnet. The magnetic field strength of the permanent magnet was measured at increments from 0 to 5.00 cm distances. The results as shown in Table 8 illustrate the substantial decay of its magnetic strength. It is expected that electromagnetic bars will exhibit similar decay. With the present invention, the strength of the magnetic field generated by the magnets must be strong enough to activate the inducing paramagnetic substances to magnetize the diamagnetic substances as the diamagnetic and inducing paramagnetic substances interact. Given that magnetic strength decays dramatically with distance, it is necessary to keep the distance between sleeve holders to a relatively small gap as discussed previously. 
     
       
         
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
               
               
               
               
               
               
             
           
               
                 TABLE 8 
               
             
             
               
                   
               
               
                   
                 Distance (cm) 
               
             
          
           
               
                   
                 0 
                 0.50 
                 0.75 
                 1.00  
                 1.25 
                 1.50  
                 1.75 
                 2.00  
                 2.25  
                 2.50 
                 3.00  
                 5.00 
               
               
                   
               
             
          
           
               
                 Mag. Field St. (GS)  
                 6000 
                 1000 
                 600  
                 250  
                 110 
                 75 
                 43 
                 40 
                 20 
                 15 
                 10 
                 1 
               
               
                   
               
             
          
         
       
     
     Example 9 
     With the present invention, in order to function as an effective magnetic filter to remove diamagnetic materials, the filter must use magnets, which can be permanent magnets or electromagnets, capable of generating sufficient magnetic fields to impart or induce the requisite magnetism in the diamagnetic materials so as to be attracted by a magnetic field. The intensity of the induced magnetism in the diamagnetic materials must to be strong enough to cause the attraction by the magnetic field. To demonstrate the importance of the magnetic field strength, 2,000 GS and 6,000 GS permanent magnetic bars were compared in a test similar to that in Example 6 where the magnets removed RFCC powders in water solution at room temperature. 
     The results are as summarized in Table 9 show that with the 2,000 GS magnet, only about 40% of the mixed powder was attracted. The amount of paramagnetic powder present in the solution did not affect the level of attraction. In contrast, with the 6,000 GS magnet, 90% and 92% of the mixed powder was removed under a PM/DM ratio of 0.1 and 0.3, respectively. Therefore, it is preferred to use magnets with higher magnetic strength to attract the diamagnetic substances through induced magnetism by the paramagnetic substances. The influence of the amount of paramagnetic powder present in the solution was comparatively less important with respect to the diamagnetic material being attracted. 
     
       
         
               
             
               
               
               
               
             
           
               
                 TABLE 9 
               
             
             
               
                   
               
               
                 Permanent Magnet Bar (MB) Strength: 2,000 and 6,000 GS 
               
             
          
           
               
                   
                   
                 para- 
                 % attracted 
               
               
                   
                   
                 magnetic 
                 by MB 
               
               
                   
                   
               
               
                   
                 2000 GS 
                   
                   
               
               
                   
                 Water:RFCC:para-magnetic = 50:1:0.1 
                 Fe2O3 
                 38.52 
               
               
                   
                 Water:RFCC:para-magnetic = 50:1:0.3 
                 Fe2O3 
                 44.43 
               
               
                   
                 6000 GS 
                   
                   
               
               
                   
                 Water:RFCC:para-magnetic = 50:1:0.1 
                 Fe2O3 
                 90.15 
               
               
                   
                 Water:RFCC:para-magnetic = 50:1:0.3 
                 Fe2O3 
                 92.23