Preparation of Y-type faujasite using an organic template

A method is disclosed for preparing crystalline aluminosilicate Y-type faujasite from a reaction mixture containing an organic template capable of producing Y-type faujasite. The reaction mixture contains only sufficient water to produce Y-type faujasite. In one embodiment, the reaction mixture is self-supporting and may be shaped if desired. In the method, the reaction mixture is heated at crystallization conditions and in the absence of an added external liquid phase, so that excess liquid need not be removed from the crystallized product prior to drying the crystals.

FIELD OF THE INVENTION 
The present invention relates to a process for producing crystalline 
aluminosilicate Y-type faujasite from a reaction mixture which contains an 
organic templating agent capable of producing Y-type faujasite and only 
sufficient water to form the Y-type faujasite. 
BACKGROUND 
Prior art methods of preparing crystalline Y zeolite typically produce 
finely divided crystals which must be separated from an excess of liquid 
in which the zeolite is crystallized. The liquid, in turn, must be treated 
for reuse or else be discarded, with potentially deleterious environmental 
consequences. Preparing commercially useful catalytic materials which 
contain the powdered zeolite also normally requires additional binding and 
forming steps. Typically, the zeolite powder as crystallized must be mixed 
with a binder material and then formed into shaped particles or 
agglomerates, using methods such as extruding, agglomeration, spray 
drying, and the like. These binding and forming steps greatly increase the 
complexity of catalyst manufacture involving zeolitic materials. The 
additional steps may also have an adverse effect on the catalytic 
performance of the Y zeolite so bound and formed. 
U.S. Pat. No. 3,094,383, issued Jun. 18, 1963 to Dzierzanowski et al., 
discloses a method for making type A zeolites in the form of coherent 
polycrystalline aggregates by forming reaction masses consisting of a 
mixture of sodium aluminate, a siliceous material and water, wherein the 
H.sub.2 O/Na.sub.2 O mole ratio is 5 to 25. The mass is aged while 
maintaining it out of contact with an external aqueous liquid phase while 
preventing the mass from dehydrating. The aging step can include 
maintaining the mass at 100.degree. F. (38.degree. C.) for, e.g., 18 
hours, followed by heating at 200.degree. F. (93.degree. C.) for, e.g., 24 
hours. 
U.S. Pat. No. 3,119,659, issued Jan. 28, 1964 to Taggart et al., discloses 
a method for producing an aluminosilicate zeolite in a preformed body by 
providing an unreacted preformed body containing a reactive kaolin-type 
clay and alkali metal hydroxide, and reacting the preformed body in an 
aqueous reaction mixture until crystals of the zeolite are formed in the 
body. The aggregate of the preformed body and the aqueous reactant mixture 
has a H.sub.2 O/Na.sub.2 O mole ratio of at least 20. It is stated that Y 
zeolite can be made in this manner. 
U.S. Pat. No. 3,777,006, issued Dec. 4, 1973 to Rundell et al., discloses a 
process for preparing zeolitic bodies having a size in excess of 200 
microns, by preparing clay bodies in the desired size range, treating the 
clay bodies in a sodium silicate solution, and heating the formed bodies 
in the solution until crystallization is complete. It is indicated that Y 
zeolite can be made in this manner. 
U.S. Pat. No. 3,972,983, issued Aug. 3, 1976 to Ciric, discloses a 
faujasite-type zeolite designated ZSM-20 made by preparing a mixture 
containing sources of an alkali metal oxide, a tetraethylammonium oxide, 
an oxide of aluminum, an oxide of silicon and water and maintaining the 
mixture at a temperature of at least 50.degree. C. until crystals of the 
zeolite are formed. The mole ratio of water to silica in the reaction 
mixture is disclosed to be 10-20. 
U.S. Pat. No. 4,058,586, issued Nov. 15, 1977 to Chi et al., discloses a 
method for preparing zeolitic aluminosilicates, particularly those that 
are characterized by pores in the 4 to 10 Angstrom sizes that are 
designated Zeolites A and X, in which compacts of Zeolites A and X, 
metakaolin clay mixture undergo crystallization at a temperature of 
200.degree. to 700.degree. F. (93.degree. to 371.degree. C.). The 
crystallization is carried out in a calciner or other drying equipment. 
Normally, the formed particles furnish all of the liquid needed for 
crystallization, though stem may be added during the crystallization 
process. 
U.S. Pat. No. 4,931,267, issued Jun. 5, 1990 to Vaughan et al., discloses a 
faujasite polymorph designated ECR-32 having a silica to alumina ratio 
greater than 6, and containing tetrapropylammonium and/or 
tetrabutylammonium trapped in the supercages of the structure. The 
reaction mixture from which the material is made has a silica to alumina 
mole ratio of 9-36 and a water to alumina mole ratio of 120-500. 
U.S. Pat. No. 5,116,590, issued May 26, 1992 to Vaughan et al., discloses a 
faujasite-type zeolite designated ECR-35 prepared from a reaction mixture 
which contains an organic cation selected from the group consisting of 
tetraethylammonium and methyltriethylammmonium or mixtures thereof. The 
reaction mixture from which the ECR-35 is prepared has a Si/Al.sub.2 ratio 
of 8-30 and a H.sub.2 O/Al.sub.2 O.sub.3 ratio of 100-600. 
WO 92/12928, published Aug. 6, 1992, discloses that silica-bound extruded 
zeolites may be converted into binder-free zeolite aggregates by aging the 
zeolite in an aqueous ionic solution which contains hydroxy ions such that 
the initial molar ratio of OH:SiO.sub.2 is up to 1.2 and which causes the 
silica binder to be converted substantially to zeolite of the type 
initially bound. It is stated that this process can be used to make Y 
zeolite. 
WO 94/13584, published Jun. 23, 1994, discloses a method for preparing a 
crystalline aluminosilicate zeolite from a reaction mixture containing 
only sufficient water so that the reaction mixture may be shaped if 
desired. In the method, the reaction mixture is heated at crystallization 
conditions and in the absence of an external liquid phase, so that excess 
liquid need not be removed from the crystallized material prior to drying 
the crystals. 
GB 2,160,517 A, published Dec. 24, 1985, relates to a preformed synthetic 
zeolite selected from the group consisting of Y, omega zeolite, offretite, 
erionite, L zeolite and ferrierite whose Si/Al atomic ratio ranges from 
1.5 to 100, the preformed zeolite being obtained from a preformed 
aluminosilicic material whose Si/Al atomic ratio is lower than that of the 
product and ranges from 0.5 to 90 by treating the material with a 
silica-containing product in the presence of at least one organic or 
inorganic base. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide a method for preparing 
crystalline Y-type faujasite using a minimum of liquid for 
crystallization. 
It is a further object of the invention to provide a method for preparing 
crystalline Y-type faujasite while minimizing aqueous waste. 
It is a further object of the invention to provide a method for preparing 
Y-type faujasite in the absence of added binder. 
It is also an object of this invention to prepare crystalline Y-type 
faujasite in the form of a shape. 
It is a further object of the invention to provide a method for preparing 
Y-type faujasite in commercially useful forms without any post 
crystallization forming steps. 
It is a further object of the invention to provide a method for preparing 
Y-type faujasite having a small crystallite size. 
It is a further object of the invention to provide a method for preparing 
Y-type faujasite at reduced raw material costs. 
Thus, in accordance with the present invention, there is provided a method 
for preparing crystalline Y-type faujasite, said method comprising 
preparing a reaction mixture comprising at least one active source of 
silica, at least one active source of alumina, and an organic templating 
agent capable of producing the Y-type faujasite in mounts sufficient to 
produce the Y-type faujasite, and sufficient water to produce the Y-type 
faujasite, and maintaining said reaction mixture at a temperature up to 
about 130.degree. C. under crystallization conditions and in the absence 
of an added external liquid phase for sufficient time to form crystals of 
the Y-type faujasite. 
The present invention also provides a method for preparing crystalline 
Y-type faujasite, said method comprising preparing a reaction mixture 
comprising at least one active source of silica, at least one active 
source of alumina, and an organic templating agent capable of producing 
the Y-type faujasite in amounts sufficient to produce the Y-type 
faujasite, and sufficient water to shape said mixture, forming said 
reaction mixture into a shape, and maintaining said reaction mixture at a 
temperature up to about 130.degree. C. under crystallization conditions 
and in the absence of an added external liquid phase for sufficient time 
to form crystals of the Y-type faujasite. 
The Y-type faujasite prepared in accordance with this invention has an 
X-ray diffraction pattern, after it has been calcined, containing the 
lines of Table I. 
It is important, in preparing the reaction mixture of the present process, 
that the amount of water present in the reaction mixture as prepared for 
the crystallization step be sufficient to produce the Y-type faujasite. 
Thus, the reaction mixture itself furnishes all the water needed to 
crystallize the zeolite. This amount of water is less than the amount of 
water required in conventional processes for preparing zeolites. It is an 
amount which is not substantially greater than that required to produce 
the Y-type faujasite. For example, the amount of water used in the present 
invention is less than that required to dissolve the reaction mixture 
components, or, if they are not dissolved, less than that required to 
immerse the reaction mixture components in the water. Thus, during the 
crystallization step according to the present process, there is no 
separate, added external liquid phase present which must be removed from 
the crystallized material at the end of the crystallization step by, for 
example filtering or decanting, prior to drying the crystals. This absence 
of an added external liquid phase distinguishes the present invention from 
methods for making Y-type faujasite wherein the Y-type faujasite crystals 
are formed from solution or where solid reactants are heated in an aqueous 
solution until crystals of Y-type faujasite form. 
While it is not a requirement to form the mixture into a shape before the 
mixture is subjected to crystallization conditions, it may be desired in 
many cases to do so. In that case, the amount of water present in the 
reaction mixture is sufficient to form the reaction mixture into a shape, 
but insufficient to cause the shaped reaction mixture to collapse or 
"melt", i.e., once the reaction mixture is formed into the desired shape 
containing the desired amount of water, the resulting shape is 
self-supporting. 
Among other factors, the present invention is based on the discovery of a 
method for crystallizing the Y-type faujasite from a reaction mixture 
which contains an organic template capable of producing the Y-type 
faujasite and which contains only enough water to form the Y-type 
faujasite. The Y-type faujasite produced by this method has a silica to 
alumina mole ratio of greater than 6. Further, the Y-type faujasite 
prepared by the above described method is made as very small crystallites. 
DETAILED DESCRIPTION OF THE INVENTION 
Preparing the Reaction Mixture 
The reaction mixture from which and in which the Y-type faujasite is 
crystallized comprises at least one active source of silica, at least one 
active source of alumina, and sufficient water to form the Y-type 
faujasite. This amount of water is considerably less than that required in 
conventional processes for preparing the Y-type faujasite. 
The amount of water required in the reaction mixture of the present 
invention is that amount which is needed to adequately blend the mixture. 
Thus, a reaction mixture is prepared by mixing water with active sources 
of the zeolite to form a uniform mass having preferably a heavy paste-like 
consistency. The active sources will be in a form which can be easily 
blended into a uniform mass, and may be, for example, powders, hydrated 
particles, or concentrated aqueous solutions. Sufficient water is added to 
wet all the powders during the mixing and kneading steps. Alternatively, 
sufficient water is added that the powders may be kneaded into a uniform 
and generally homogeneous mixture which may be shaped. It is not necessary 
that all of the active sources be readily soluble in water during 
kneading, since the water added to the active sources will be insufficient 
to make a fluid-like mixture. The amount of water added depends on the 
mixing apparatus and on the active sources employed. Those familiar with 
the art can readily determine without undue experimentation the amount of 
liquid required to properly mix active sources of the zeolite. For 
example, hydrated sources of the zeolite may require relatively less 
water, and dried sources may require relatively more. Though it is 
preferred that the mixture be blended and kneaded until the mixture has a 
uniform, homogeneous appearance, the length of time devoted to kneading 
the mixture is not critical in the present invention. 
The water content of the reaction mixture after blending and kneading may 
be further adjusted, for example, by drying or by the addition of water. 
When it desired that the reaction mixture be formed into a shape, 
adjusting the amount of water can facilitate shaping the reaction mixture 
and ensure that it will be self-supporting, i.e., the shape will not 
collapse or "melt" due to an excess of water in the reaction mixture. 
Typical sources of silicon oxide (SiO.sub.2) include silicates, silica 
hydrogel, silicic acid, colloidal silica, fumed silica, tetraalkyl 
orthosilicates silica hydroxides, precipitated silica and clays. Typical 
sources of aluminum oxide (Al.sub.2 O.sub.3) include aluminates, alumina, 
and aluminum compounds such as AlCl.sub.3, Al.sub.2 (SO.sub.4).sub.3, 
aluminum hydroxide (Al(OH.sub.3)), and kaolin clays. One advantage of the 
present invention is that the sources of silicon oxide and aluminum oxide 
can all be non-zeolitic. 
Salts, particularly alkali metal halides such as sodium chloride, can be 
added to or formed in the reaction mixture. They are disclosed in the 
literature as aiding the crystallization of zeolites while preventing 
silica occlusion in the lattice. 
The reaction mixture also contains one or more active sources of alkali 
metal oxide. Sources of lithium, sodium and potassium, are preferred. Any 
alkali metal compound which is not detrimental to the crystallization 
process is suitable here. Non-limiting examples include oxides, 
hydroxides, nitrates, sulfates, halogenides, oxalates, citrates and 
acetates. The alkali metal is generally employed in an amount so that the 
alkali metal/aluminum ratio is at least 1/1, preferably greater than 1/1. 
The reaction mixture also contains an organic templating agent capable of 
producing Y-type faujasite. These organic templating agents are typically 
quaternary ammonium cations such as tetraethylammonium, 
tetrapropylammonium, or tetrabutylammonium cations. Tetraethyl ammonium 
compounds are the preferred organic template. The counter ion for the 
quaternary ammonium compounds may be essentially any anion such as halide 
or hydroxide which is not detrimental to the formation of the Y-type 
faujasite. As used herein, "halide" refers to the halogen anions, 
particularly fluorine, chlorine, bromine, iodine, and combinations 
thereof. Thus, representative anions include hydroxide, acetate, sulfate, 
carboxylate, tetrafluoroborate, and halides such as fluoride, chloride, 
bromide, and iodide. Hydroxide and iodide are particularly preferred as 
anions. 
The organic templating agent is used in an amount which is sufficient to 
produce the Y-type faujasite. 
The reaction mixture should contain the following components in the amounts 
indicated (expressed as mole ratios of oxides even though the actual 
starting materials may not be oxides): 
______________________________________ 
General 
Preferred 
______________________________________ 
SiO.sub.2 /Al.sub.2 O.sub.3 = 
6-15 6-12 
M.sup.+ /SiO.sub.2 = 
0.2-1.0 0.3-0.7 
OH.sup.- /SiO.sub.2 = 
0.1-0.5 0.2-0.4 
R/SiO.sub.2 = 0.05-0.5 0.1-0.4 
H.sub.2 O/SiO.sub.2 = 
1-5 2-5 
______________________________________ 
wherein M.sup.+ is an alkali metal cation and R is the organic templating 
agent. 
Forming the Shapes 
One advantage of the present invention is that the reaction mixture may be 
formed into a desired shape before the crystallization step, thereby 
reducing the number of process steps required to prepare catalytic 
materials containing the resulting zeolite. Prior to forming the reaction 
mixture, it may be necessary to change the liquid content of the reaction 
mixture, either by drying or by adding more liquid, in order to provide a 
formable mass which retains its shape. In general, for most shaping 
methods, water will generally comprise from about 20 percent to about 60 
percent by weight, and preferably from about 30 percent to about 50 
percent by weight of the reaction mixture. 
The reaction mixture is formed into a shape, e.g., particles. Methods for 
preparing such shapes are well known in the art, and include, for example, 
extrusion, spray drying, granulation, agglomerization and the like. When 
the shape is in the form of particles, they are preferably of a size and 
shape desired for the ultimate catalyst, and may be in the form of, for 
example, extrudates, cylinders, spheres, granules, agglomerates and 
prills. The particles will generally have a cross sectional diameter 
between about 1/64 inch and about 1/2 inch, and preferably between about 
1/32 inch and about 1/4 inch, i.e., the particles will be of a size to be 
retained on a 1/64 inch, and preferably on a 1/32 inch screen and will 
pass through a 1/2 inch, and preferably through a 1/4 inch screen. 
The shape prepared from the reaction mixture will contain sufficient water 
to retain a desired shape. Additional water is not required in the mixture 
in order to initiate or maintain crystallization within the shaped 
reaction mixture. Indeed, it may be preferable to remove some of the 
excess water from the shaped reaction mixture prior to crystallization. 
Conventional methods for drying wet solids can be used to dry the reaction 
mixture, and may include, for example drying in air or an inert gas such 
as nitrogen or helium at temperatures below about 200.degree. C. and at 
pressures from subatmospheric to about 5 atmospheres pressure. 
Naturally occurring clays, e.g., bentonite, kaolin, montmorillonite, 
sepiolite and attapulgite, are not required, but may be included in the 
reaction mixture prior to crystallization to provide a product having good 
crush strength. Such clays can be used in the raw state as originally 
mined or can be initially subjected to calcination, acid treatment or 
chemical modification. Microcrystalline cellulose has also been found to 
improve the physical properties of the particles. 
Zeolite Crystallization 
According to the present process, the zeolite is crystallized either within 
the reaction mixture or within the shape made from the reaction mixture. 
In either case, the composition of the mixture from which the zeolite is 
crystallized has the molar composition ranges stated above. 
It is preferred that the total volatiles content of the reaction mixture 
during crystallization be in the range of between about 20 wt. % and about 
60 wt. %, and preferably between about 30 wt. % and about 60 wt. %, based 
on the weight of the reaction mixture, where the total volatiles content 
is the measure of total volatile liquid, including water, in the reaction 
mixture. It is a feature of the present process that no additional liquid 
beyond that required to produce the Y-type faujasite is required for 
zeolite crystallization. 
Crystallization of the zeolite takes place in the absence of an added 
external liquid phase, i.e., in the absence of a liquid phase separate 
from the reaction mixture. In general, it is not detrimental to the 
present process if some liquid water is present in contact with the 
reaction mixture during crystallization, and it can be expected that some 
water may be on the surface of the reaction mixture during 
crystallization, or that some water may be expelled from the reaction 
mixture and may collect on or near the reaction mixture as the reaction 
progresses. However, it is an objective of the present invention to 
provide a method of crystallizing the zeolite in such a way as to minimize 
the amount of water which must be treated and/or discarded following 
crystallization. To that end, the present method provides a zeolite 
synthesis method which requires no additional water for crystallization 
beyond a sufficient amount of liquid required to form the Y-type 
faujasite. 
Once the reaction mixture has been formed it is preferably "aged" before 
the Y-type faujasite is crystallized. This aging is accomplished by 
maintaining the reaction mixture at a relatively low temperature (compared 
to the crystallization temperature) under conditions which will prevent 
dehydration of the reaction mixture (such as placing the mixture in a 
sealed container and/or exposing it to a small amount of water vapor). 
Thus, the reaction mixture is maintained at room temperature or a slightly 
higher temperature. Typically, the temperature at which the mixture is 
aged will be from about 25.degree. C. to about 75 C., preferably from 
about 25.degree. C. to about 50.degree. C. This temperature should be 
maintained for a time sufficient to provide the crystalline Y-type 
faujasite following the crystallization step. It is believed it is within 
the skill of one skilled in this art to readily determine the length of 
this aging step without undue experimentation. In general, the aging 
should be continued long enough to allow Y-type faujasite nuclei to begin 
to form in the reaction mixture. Typically, though, the aging step will be 
at least 24 hours, preferably 2 days or longer (e.g., 2-4 days), with 
longer aging times leading to a more crystalline product. 
Crystallization is conducted after the aging step at an elevated 
temperature and usually in an autoclave so that the reaction mixture is 
subject to autogenous pressure until the crystals of zeolite are formed. 
The temperatures during the hydrothermal crystallization step are 
typically maintained from about 70.degree. C. to about 130.degree. C., 
preferably from about 80.degree. C. to about 120.degree. C. If the 
crystallization temperature is too high, the resulting product may be 
zeolite beta, not Y-type faujasite. 
The crystallization is conducted under conditions which will prevent 
dehydration of the reaction mixture. This may be accomplished by exposing 
the reaction mixture to a small amount of water vapor or steam during 
crystallization. 
It is believed it is well within the skill of one skilled in this art to 
determine a satisfactory crystallization time without undue 
experimentation. The crystallization time required to form crystals will 
typically range from about 1 day to about 10 days, and more frequently 
from about 1 day to about 4 days. If the crystallization period is too 
long, the zeolite formed will be zeolite Beta, not Y-type faujasite. 
It has been found that the best product was obtained by a combination of 
aging and crystallization conditions comprising 1 day at room temperature, 
followed by 1 day at 45.degree. C., followed by 39 hours at 100.degree. C. 
In the present method, the crystallized material collected following the 
crystallization step will typically comprise at least about 50 weight 
percent crystals. Crystallized material containing at least about 80 
weight percent crystals, and even at least about 90 weight percent 
crystals, may also be prepared using the present method. 
Once the zeolite crystals have formed, the crystals may be water-washed and 
then dried, e.g., at 90.degree. C. to 150.degree. C. for from 8 to 24 
hours. The drying step can be performed at atmospheric or subatmospheric 
pressures. 
Seed Crystals 
The zeolite made by the present process is crystallized within the reaction 
mixture, which comprises amorphous reagents. Crystalline material (i.e., 
"seed" crystals of Y-type faujasite) may be added to the mixture prior to 
the crystallization step, and methods for enhancing the crystallization of 
zeolites by adding "seed" crystals are well known. However, the addition 
of seed crystals is not a requirement of the present process. Indeed, it 
is an important feature of the present process that the zeolite can be 
crystallized within the reaction mixture in the absence of crystals added 
prior to the crystallization step. 
DESCRIPTION OF THE Y-TYPE FAUJASITE 
The Y-type faujasite prepared in accordance with this invention and 
calcined is characterized by the X-ray diffraction lines in Table I below. 
In Table I, d is the distance between two lattice planes, and I/I.sub.0 is 
the ratio, expressed in percent, of the intensity of any given line (I) to 
the intensity of the most intense line (I.sub.0). The strongest line is 
assigned a value of 100. In Table I, the intensities are indicated as W 
(weak--less than 20), M (medium--20-40), S (strong--40-60) and VS (very 
strong--greater than 60). In Table IA, actual relative intensities are 
shown. Of course, distances as well as relative intensities may be subject 
to small variations according to the product analyzed. Such variations do 
not indicate a change of structure but are due to the replacement of 
certain cations or to a deviation in the silica/alumina ratio. 
TABLE I 
______________________________________ 
2 Theta d (.ANG.) 
I/I.sub.0 
______________________________________ 
5.87 15.05 S 
6.14 14.38 VS 
10.08 8.77 M 
11.83 7.47 M 
15.58 5.68 VS 
18.63 4.76 M 
20.31 4.37 S 
22.78 3.90 W 
23.58 3.77 VS 
27.01 3.29 S 
29.60 3.02 W 
30.73 2.91 M 
31.37 2.85 M 
______________________________________ 
TABLE IA 
______________________________________ 
2 Theta d (.ANG.) 
I/I.sub.0 
______________________________________ 
5.87 15.05 57 
6.14 14.38 100 
10.08 8.77 37 
11.83 7.47 38 
15.58 5.68 67 
18.63 4.76 24 
20.31 4.37 46 
22.78 3.90 16 
23.58 3.77 72 
27.01 3.29 55 
29.60 3.02 15 
30.73 2.91 25 
31.37 2.85 55 
______________________________________ 
The Y-type faujasite produced by the present invention typically has a 
silica/alumina mole ratio of greater than 6, preferably from greater than 
6 to about 15, more preferably from greater than 6 to about 10. The 
silica/alumina mole ratio of the product zeolite can be determined from a 
corelation with the unit cell constant as calculated from X-ray 
diffraction analysis (see Sohn et al., Zeolites, 6, 225 (86)). The Y-type 
faujasites produced by the present application include zeolites such as 
ZSM-20, ECR-32 and ECR-35. 
Zeolite Crystallite Size 
Typically, the zeolite crystals are less than 10 microns in diameter as 
determined by Scanning Electron Microscopy. Since small crystals are 
desirable for certain catalytic applications, crystallization conditions 
can be tailored to produce zeolite crystals with diameters of less than 
1.0 micron. The crystal size of the zeolite may be determined by, for 
example, grinding the shaped particles to separate the individual 
crystals. High resolution electron micrographs of the separated crystals 
can then be prepared, after which the average size of individual zeolite 
crystals can be determined by reference to calibrated length standards. An 
average crystal size may then be computed in various well-known ways, 
including: 
##EQU1## 
where n.sub.i is the number of zeolite crystals where minimum length falls 
within an interval L.sub.i. For purposes of this invention, average 
crystal size will be defined as a number average. It is important to note 
that for purposes of this invention, zeolite crystal size is distinguished 
from what some manufacturers term "zeolite particle size," the latter 
being the average size of all particles, including both individual 
crystals and polycrystalline agglomerates, in the as-produced zeolite 
powder. 
Typically, the zeolite crystals are less than 10 microns in diameter as 
determined by Scanning Electron Microscopy. Since small crystals are 
desirable for certain catalytic applications, crystallization conditions 
can be tailored by, for example, reducing crystallization temperature, by 
increasing aluminum content in the reaction mixture, and/or by reducing 
the water content of the reaction mixture or the shaped particles prior to 
crystallization, to produce zeolite crystals with diameters of less than 
1.0 micron. 
Zeolite Post-Treatment 
A crystallized material containing crystals of zeolite is prepared in the 
process as described above. The zeolite can be used as synthesized or can 
be thermally treated (calcined). In some cases, the synthesis product can 
contain silica which is not incorporated in the zeolite structure. This 
excess silica can be removed by washing with dilute acid (e.g., 0.2M 
HNO.sub.3) or dilute base (e.g., 0.01M NH.sub.4 OH). This washing should 
be done prior to thermal treatment of the zeolite. Usually, it is 
desirable to remove the alkali metal cation by ion exchange and replace it 
with hydrogen, ammonium, or any desired metal ion. The zeolite can be 
leached with chelating agents, e.g., EDTA or dilute acid solutions, to 
increase the silica/alumina mole ratio. These methods may also include the 
use of (NH.sub.4).sub.2 SiF.sub.6 or acidic ion-exchange resin treatment. 
The zeolite can also be steamed; steaming helps stabilize the crystalline 
lattice to attack from acids. The zeolite can be used in intimate 
combination with hydrogenating components, such as tungsten, vanadium, 
molybdenum, rhenium, nickel, cobalt, chromium, manganese, or a noble 
metal, such as palladium or platinum, for those applications in which a 
hydrogenation/dehydrogenation function is desired. Typical replacing 
cations can include metal cations, e.g., rare earth, Group IA, Group IIA 
and Group VIII metals, as well as their mixtures. Of the replacing 
metallic cations, cations of metals such as rare earth, Mn, Ca, Mg, Zn, 
Ga, Cd, Pt, Pd, Ni, Co, Ti, Al, Sn, Fe and Co are particularly preferred. 
The hydrogen, ammonium, and metal components can be exchanged into the 
zeolite. The zeolite can also be impregnated with the metals, or, the 
metals can be physically intimately admixed with the zeolite using 
standard methods known to the art. The metals can also be occluded in the 
crystal lattice by having the desired metals present as ions in the 
reaction mixture from which the zeolite is prepared. 
Typical ion exchange techniques involve contacting the synthetic zeolite 
with a solution containing a salt of the desired replacing cation or 
cations. Although a wide variety of salts can be employed, chlorides and 
other halides, nitrates, and sulfates are particularly preferred. 
Representative ion exchange techniques are disclosed in a wide variety of 
patents including U.S. Pat. Nos. 3,140,249; 3,140,251; and 3,140,253. Ion 
exchange can take place either before or after the zeolite is calcined. 
Following contact with the salt solution of the desired replacing cation, 
the zeolite is typically washed with water and dried at temperatures 
ranging from 65.degree. C. to about 315.degree. C. After washing, the 
zeolite can be calcined in air or inert gas at temperatures ranging from 
about 200.degree. C. to 820.degree. C. for periods of time ranging from 1 
to 48 hours, or more, to produce a catalytically active product especially 
useful in hydrocarbon conversion processes. 
Regardless of the cations present in the synthesized form of the zeolite, 
the spatial arrangement of the atoms which form the basic crystal lattice 
of the zeolite remains essentially unchanged. The exchange of cations has 
little, if any, effect on the zeolite lattice structures. 
The zeolite may be used as a catalyst, without additional forming, if the 
reaction mixture has been formed into a shape which is of a size and shape 
desired for the ultimate catalyst. Alternatively, the zeolite can be 
composited with other materials resistant to the temperatures and other 
conditions employed in organic conversion processes, using techniques such 
as spray drying, extrusion, and the like. Such matrix materials include 
active and inactive materials and synthetic or naturally occurring 
zeolites as well as inorganic materials such as clays, silica and metal 
oxides. The latter may occur naturally or may be in the form of gelatinous 
precipitates, sols, or gels, including mixtures of silica and metal 
oxides. Use of an active material in conjunction with the synthetic 
zeolite, i.e., combined with it, tends to improve the conversion and 
selectivity of the catalyst in certain organic conversion processes. 
Inactive materials can suitably serve as diluents to control the amount of 
conversion in a given process so that products can be obtained 
economically without using other means for controlling the rate of 
reaction. Frequently, zeolite materials have been incorporated into 
naturally occurring clays, e.g., bentonite and kaolin. These materials, 
i.e., clays, oxides, etc., function, in part, as binders for the catalyst. 
It is desirable to provide a catalyst having good crush strength, because 
in petroleum refining the catalyst is often subjected to rough handling. 
This tends to break the catalyst down into powders which cause problems in 
processing. 
Naturally occurring clays which can be composited with the synthetic 
zeolite of this invention include the montmorillonite and kaolin families, 
which families include the sub-bentonites and kaolins commonly known as 
Dixie, McNamee, Georgia and Florida clays or others in which the main 
mineral constituent is halloysite, kaolinite, dickite, nacrite, or 
anauxite. Fibrous clays such as sepiolite and attapulgite can also be used 
as supports. Such clays can be used in the raw state as originally mined 
or can be initially subjected to calcination, acid treatment or chemical 
modification. 
In addition to the foregoing materials, the zeolite prepared by the present 
method can be composited with porous matrix materials and mixtures of 
matrix materials such as silica, alumina, titania, magnesia, 
silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, 
silica-beryllia, silica titania, titania-zirconia as well as ternary 
compositions such as silica-alumina-thoria, silica-alumina-zirconia, 
silica-alma-magnesia and silica-magnesia-zirconia. The matrix can be in 
the form of a cogel. 
The zeolite can also be composited with other zeolites such as synthetic 
and natural faujasites (e.g., X), and erionites. They can also be 
composited with purely synthetic zeolites such as those of the ZSM, SSZ, 
KU, FU, and NU series. The combination of zeolites can also be composited 
in a porous inorganic matrix. 
The zeolite prepared in the present process is useful in hydrocarbon 
conversion reactions. Hydrocarbon conversion reactions are chemical and 
catalytic processes in which carbon containing compounds are changed to 
different carbon containing compounds. Examples of hydrocarbon conversion 
reactions include isomerization of C.sub.5 and C.sub.6 compounds to 
increase the octane of gasoline, hydocracking, fluid catalytic cracking, 
butane alkylation for fuels, aromatics alkylation, aromatics isomerization 
and olefin polymerization.

EXAMPLES 
Example 1 
150 Grams of silica (Hi-Sil 233, a hydrated silica manufacture by PPG) was 
placed in a Baker-Perkins mixer. 50 Grams of NaAlO.sub.2 was added to the 
mixer and the two were mixed for about ten minutes. Then 19 grams of a 50% 
NaOH aqueous solution and 190 grams of a 35% tetraethylammonium hydroxide 
solution was slowly added to the mixer and mixing continued for about 3 
hours. Deionized water (40 grams) was then added slowly to the mixer to 
form a paste-like mixture. Heat (66.degree. C.) was applied to the mixture 
to dry it slightly (to about 50% volatiles) and make it extrudable, and 
the mixture was stored overnight at room temperature in a sealed 
container. 
The mixture was extruded and the extrudates divided into four parts (A, B, 
C and D). Parts A and B contained 49.3% volatiles, and parts C and D were 
air dried to 45% volatiles. 
Each of parts A, B, C and D was placed in its own one quart Teflon bottle 
with a hole in the cover, and each bottle was sealed in an autoclave which 
contained 12 cc water outside the bottles to prevent drying of the samples 
when heated (especially small samples in large autoclaves). At the end of 
crystallization, there was still about 12 cc water outside the bottles, so 
consumption of this water was negligible. The bottles were then left at 
room temperature for 24 hours. The bottles containing parts A and C were 
then heated at 110.degree. C. for two days, and the bottles containing 
parts B and D were heated at 110.degree. C. for four days. 
The resulting crystalline extrudates were washed with deionized water, 
filtered, dried in a vacuum oven at 120.degree. C. overnight and calcined 
for 6 hours at 593.degree. C. The products were analyzed by X-ray 
diffraction and determined to be the Y-type faujasite of this invention. 
The XRD lines for part B are indicated in Table II below. 
TABLE II 
______________________________________ 
2 Theta d (.ANG.) 
I/I.sub.0 
______________________________________ 
2.59 34.08 6.13 
3.18 27.76 3.69 
4.17 21.17 3.27 
5.87 15.05 56.67 
6.14 14.38 100.00 
6.55 13.48 11.01 
7.40 11.93 5.66 
7.75 11.40 2.15 
10.08 8.77 37.37 
11.83 7.47 37.52 
13.43 6.59 7.00 
14.82 5.98 3.10 
15.58 5.68 67.16 
18.24 4.86 4.24 
18.63 4.76 23.71 
20.32 4.37 45.69 
21.66 4.10 5.00 
22.78 3.90 15.87 
23.58 3.77 71.59 
24.92 3.57 5.32 
25.75 3.46 8.47 
27.01 3.30 55.15 
27.73 3.21 6.62 
29.60 3.02 15.25 
30.73 2.91 25.28 
31.37 2.85 54.74 
32.43 2.76 13.83 
33.09 2.70 8.14 
34.07 2.63 13.77 
34.59 2.59 7.90 
35.62 2.52 2.97 
37.13 2.42 3.68 
37.90 2.37 12.04 
41.42 2.18 5.61 
41.86 2.16 2.90 
______________________________________ 
Example 2 
150 Grams of silica (Hi-Sil 233, a hydrated silica manufacture by PPG) was 
placed in a Baker-Perkins mixer. 50 Grams of NaAlO.sub.2 was added to the 
mixer and the two were mixed for about ten minutes. Then 19 grams of a 50% 
NaOH solution and 190 grams of a 35% tetraethylammonium hydroxide solution 
was slowly added to the mixer and mixing continued for about 3 hours. 
About one half of the mixture was removed from the mixer (volatiles content 
53.63%) and divided into parts A and B and stored at room temperature for 
24 hours. The half of the mixture remaining in the mixer was mixed while 
adding 25 grams of deionized water to achieve a paste-like consistency. 
Heat (about 66.degree. C.) was applied to the mixture until a volatiles 
content of about 50% was achieved. This mixture was then sealed in a 
container and let stand at room temperature overnight. This mixture was 
not extrudable, and was divided into parts C and D and crystallized as it 
was (dry powder form). 
Parts A and B were extruded and each of parts A, B, C and D was placed in 
its own one quart Teflon bottle with a hole in the cover, and each bottle 
was sealed in an autoclave which contained 12 cc water outside the 
bottles. The bottles were then left at room temperature for 24 hours. The 
bottles containing parts A and C were then heated at 110.degree. C. for 
two days, and the bottles containing parts B and D were heated at 
110.degree. C. for four days. 
One half of each of the resulting crystalline products was washed with 
deionized water, and the other half washed with a 10% NH.sub.4 NO.sub.3 
solution containing 0.6 cc HNO3 per 100 grams of solution. The products 
were dried in a vacuum oven at 120.degree. C. overnight and calcined for 6 
hours at 593.degree. C. The products were analyzed by X-ray diffraction 
and determined to be the Y-type faujasite of this invention. The X-ray 
diffraction lines for part D are indicated in Table III below. 
TABLE III 
______________________________________ 
2 Theta d (.ANG.) 
I/I.sub.0 
______________________________________ 
3.37 26.21 3.63 
3.69 23.90 5.65 
5.18 17.04 4.22 
5.85 15.10 51.97 
6.14 14.37 100.00 
7.50 11.77 5.04 
10.10 8.76 37.49 
11.84 7.47 34.39 
13.41 6.60 30.53 
15.60 5.68 59.25 
16.76 5.29 4.26 
17.52 5.06 5.15 
18.65 4.76 29.00 
19.60 4.53 5.53 
20.33 4.37 43.03 
21.30 4.17 12.26 
22.36 3.97 13.92 
22.42 3.96 15.66 
22.91 3.88 34.08 
23.61 3.77 69.5 
24.56 3.62 3.07 
24.94 3.57 7.05 
25.76 3.45 12.82 
27.03 3.30 56.45 
27.73 3.21 8.93 
28.51 3.13 5.28 
29.62 3.01 31.92 
30.76 2.91 34.09 
31.38 2.85 52.12 
32.45 2.76 13.09 
33.05 2.71 8.61 
34.10 2.63 12.19 
34.56 2.59 9.22 
35.13 2.55 6.51 
37.89 2.37 11.12 
40.00 2.25 3.85 
40.58 2.22 2.14 
41.03 2.20 5.95 
41.43 2.18 9.61 
______________________________________ 
Example 3 
600 Grams of silica (Hi-Sil 233, a hydrated silica manufacture by PPG) was 
placed in a Baker-Perkins mixer. 200 Grams of NaAlO.sub.2 was added to the 
mixer and the two were mixed for about ten minutes. Then 76 grams of a 50% 
NaOH solution and 760 grams of a 35% tetraethylammonium hydroxide solution 
was slowly added to the mixer and mixing continued for about 3 hours. Then 
50 grams of deionized water was added and mixing continued until the 
mixture reached a paste-like consistency. 
Heat (about 66.degree. C.) was applied to the mixture until a volatiles 
content of about 50% was achieved. This mixture was then sealed in a 
container and let stand at room temperature overnight. The mixture was 
heated again until the volatiles content was 48%. 
The resulting mixture was divided into six parts (A-F) which were aged and 
crystallized as follows: 
______________________________________ 
Part Aging Crystallization 
______________________________________ 
A 1 day at room temp. 
4 days at 110.degree. C. 
B 1 day at room temp. 
7 days at 110.degree. C. 
C 2 days at room temp. 
4 days at 110.degree. C. 
D 2 days at room temp. 
7 days at 110.degree. C. 
E 1 day at 45.degree. C. 
4 days at 110.degree. C. 
F 1 day at 45.degree. C. 
7 days at 110.degree. C. 
______________________________________ 
Each of parts A-F was placed in its own one quart Teflon bottle with a hole 
in the cover, and each bottle was sealed in an autoclave which contained 
12 cc water outside the bottles. The bottles were aged in the autoclave 
for the time and at the temperature indicated above, except for parts A 
and B where aging started at the end of the first day. 
The resulting crystalline products were washed with an acid solution 
containing 0.6 cc HNO.sub.3 per 100 grams of solution. The products were 
dried in a vacuum oven at 120.degree. C. overnight and calcined for 6 
hours at 593.degree. C. The products were analyzed by X-ray diffraction 
and determined to be the Y-type faujasite of this invention. The X-ray 
diffraction lines for part E are shown in Table IV below. 
TABLE IV 
______________________________________ 
2 Theta d (.ANG.) 
I/I.sub.0 
______________________________________ 
2.06 42.90 5.49 
3.02 29.26 7.33 
3.30 26.75 3.01 
5.99 14.74 56.44 
6.24 14.16 100.00 
7.39 11.96 7.89 
10.20 8.67 31.07 
11.04 8.01 11.85 
11.93 7.41 29.54 
12.95 6.83 7.04 
15.68 5.65 63.31 
17.00 5.21 4.42 
17.26 5.13 3.47 
18.75 4.73 28.64 
20.43 4.34 54.19 
21.41 4.15 6.01 
22.53 3.93 15.15 
22.82 3.89 16.21 
23.32 3.81 19.79 
23.71 3.75 61.73 
25.06 3.55 7.45 
25.86 3.44 14.67 
27.13 3.28 60.45 
27.86 3.20 10.09 
28.73 3.11 5.81 
28.96 3.08 4.43 
29.73 3.00 13.45 
30.86 2.90 32.24 
31.47 2.84 57.08 
32.22 2.78 5.40 
32.57 2.75 20.03 
33.23 2.69 6.91 
34.20 2.62 13.25 
37.27 2.41 5.30 
37.99 2.37 14.38 
39.26 2.29 5.91 
41.53 2.17 8.76 
______________________________________