MXPA97000128A - Zeolite layers with controlled width of crystals and orientation, which grow up on a layer that increases growth - Google Patents

Abstract

The present invention is directed to a new zeolite composition, which has a mesoporous growth-enhancing layer and a zeolite crystal layer on top of this growth-enhancing mesoporous layer, and wherein said mesoporous growth-increasing layer comprises zeolites. nanocrystalline or colloidal-sized, nanocrystalline zeolites and colloidal zeolites and metal oxide, or nanocrystalline or colloidal zeolites and a colloidal metal, or nanocrystalline or colloidal zeolites, a colloidal metal and metal oxide, and where this growth-enhancing mesoporous layer has interstices of about 20 to 2000Å and the zeolite layer is a polycrystalline layer of oriented crystals, with similar tendencies, where 99.9% of the zeolite crystals have at least one adjacent crystal point which is < _20 A. The invention also addresses a process for producing and using said composition

Description

ZEOLITE LAYERS WITH CONTROLLED WIDTH OF CRYSTALS AND PREFERRED ORIENTATION. WHICH GROW UP ON A LAYER THAT INCREASES GROWTH Field of the Invention The present invention is directed toward a new composition of matter comprising a zeolite layer, a growth enhancing layer, and a support. BACKGROUND OF THE INVENTION Zeolite membranes have long been a goal of the science of separations. For a zeolite membrane to be practical, it must have a high flux at the same level as selectivity. Obtaining such a membrane has been difficult in the past, due to the defects of the zeolite film. This has been especially true for membranes that grow from the alkaline synthesis routes described in the literature. These membranes have a heterogeneous crystal structure in the membrane and require a huge thickness of the layer (> 50 microns) to seal the tiny holes and void structures. The technique needs a thin zeolite membrane with very few defects. A patent, which describes the direct synthesis of zeolite membranes, has been issued to W. Haag and J. G. Tsi Oyiannis, Mobil (patent of E. U. A., No. 5,110,478, issued May 5, 1992). A document describing the scientific results obtained with this type of membrane was published in an article titled Synthesis and Character izat ion of a Zeolitic Membrane Puré (Synthesis and Characterization of a Pure Zeolite Membrane), by JG Tsikoyiannis and W. Haag in Zeolites (Vol. 12, page 126, 1992). The membrane described in the previous article and in the patent are used as a membrane of free placement and not fixed or bonded as a layer to a porous support, making it mechanically fragile and leading to its easy rupture during its use. The physical structure of the membrane is such that there is a gradient of crystal sizes across the thickness of the membrane. This gradient of crystal sizes throughout the thickness of the layer prevents the growth of a thin membrane with a minimum number of non-selective permeation paths. Zeolites have also grown on supports. See, for example, High temperature stainless steel supported zeolite (MFI) membranes: preparation, module construction and permeation experiment (Zeolite membranes supported in stainless steel at high temperature (MFI): preparation experiments, module construction and permeation), ER Geus, H. van Bekkum, W. Bakker and J. Moulijn, in Microporous Materials, Vol. 1, p. 137, 1993; Dutch patent application 9011048; European patent application 91309239 and patent of E. U. A., No. 4,099,692. All the membranes prepared above, are formed with several zones (larger crystals that grow on the top of smaller crystals) through the thickness of the membrane. In several areas, the crystals do not grow on a dense mat that is free of intercrystalline voids. To obtain the permeation-selective zeolite membrane, the above zeolite layers (comprised of zones) must grow with excessive thickness (> 50 microns) to seal and separate voids and defects within the membrane. This creates a great resistance to mass transfer, causing a reduced flow. Obtaining functional zeolite membranes from highly alkaline synthesis routes is difficult because the heterogeneous crystals in the membrane require a huge thickness of the membrane to seal the tiny holes and void structures that decrease the selectivity of the membrane. The presence of these tiny, hollow holes is the cause of the optical dispersion in highly alkaline synthesized membranes. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1, 2 and 3 show the X-ray diffraction patterns of compositions comprising a porous support having a growth-enhancing layer thereon and a zeolite layer growing on the layer which increases growth, in which this growth-increasing layer is inverted, as described herein, during the growth of the zeolite layer. The x axis represents 2 theta and the y axis is the intensity in CPS. Figures 1 and 2 show compositions having preferred crystallographic orientations of the C-axis of different grades. Figure 3 shows a composition having the axis orientation. Figure 4 shows a scanning electron micrograph of the morphology of an MFI zeolite layer, a Growth Enhancing layer, and a porous substrate, according to the present invention, which was fractured to reveal a cross section. This layer, labeled (A) is a porous substrate formed of α-alumina with 800 Á pores. The labeled layer (B) is a GEL layer, which is mesoporous and clearly discernable in the micrograph. The labeled layer (C) contains crystals of MFI zeolite, which inter-grow together on a dense mat. The columnar nature of the zeolite crystals used is readily apparent from the morphology of the fracture surface through the zeolite layer. The layer (C) is substantially free of voids and defects. Figure 4 (b) shows a scanning electron micrograph of the same composition as Figure 4 (a) only at a larger amplification in which more details can be seen about the interleaving of layers (A) and (B) . Figure 5 shows a scanning electron micrograph of the outer surface of a membrane of the present invention. The surface shown is a dense mat of intergrowth of the zeolite crystals, which are substantially free of defects that extend through the thickness of the layer. Figure 6 is a schematic view of the morphology in cross section, described herein, of one of the present compositions. (A) is the porous substrate, (B) is the layer that increases growth, (C) is a layer of zeolite, (D) is the grain limit, (T) is the thickness of a crystal of zeolite and ( W) is the width of a zeolite crystal at a point on the crystal. SUMMARY OF THE INVENTION One aspect of the present invention is directed toward a novel composition containing zeolite, which comprises a porous substrate (also referred to herein as a support) having coated thereon a mesoporous layer that increases growth and a layer of zeolite crystals on the mesoporous layer that increases growth, and in which the mesoporous layer that increases growth comprises zeolites; zeolite and metal oxide, zeolites and metal particles; or zeolites, metal particles and metal oxides, in which the zeolites are selected from the group consisting of nanocrystalline zeolites and colloidal size zeolites, and in which the mesoporous growth-increasing layer has interstices of about 20 to 2000 A, and wherein the zeolite layer is a polycrystalline layer. Preferably at least 99% of the zeolite crystals in the zeolite layer have at least one point between adjacent crystals, i.e. < 20 A. The zeolite layer will exhibit, in cross section, a set of crystals of similar tendencies. Preferably, a zeolite layer comprised of MFI-type zeolites will be prepared by exhibiting in cross-section a set of columnar trend crystals. The invention is also directed to a process for producing a zeolite-containing composition, which comprises: (a) coating a substrate with a growth-increasing layer, wherein this growth-increasing layer is prepared using a solution comprising zeolite; zeolite and metal oxide; zeolite and colloidal metal, or zeolite, colloidal metal and metal oxide; and wherein said zeolite is selected from the group consisting of the nanocrystalline and colloidal zeolite and where the metal oxide is a colloidal metal oxide or a polymeric metal oxide, prepared by the sol-gel process, followed by calcination at a temperature of about 200 to 1000 ° C for at least 2 hours; (b) contacting the substrate, which has a growth-increasing layer, coated with a zeolite synthesis mixture; (c) treating the synthesis mixture of the substrate and the zeolite hydrothermally for a time and at a temperature sufficient to form the zeolite layer on the growth-increasing layer, and in which the sedimentation of the particles produced from the mixture is prevented. synthesis of the zeolite on the zeolite layer; (d) removing the synthesis mixture from the unreacted zeolite. The contact, as used herein, includes total and partial immersion. The solution of step (a) will contain a solvent, preferably water (distilled, deionized, demineralized) etc. The process further comprises step (e) of calcining the composition when the synthesis mixture of the zeolite contains an organic model, for a time and at a temperature sufficient to remove this organic model. The compositions of the present invention (which may be referred to as zeolite membranes) have a large number of applications in separations. For example, they can be used in the separation of CO2 from the membrane, alcohol and water separations, hydrogen recovery, separation of xylenes and several other molecular separations. The compositions are also useful in the catalyst reactions. The compositions are often referred to in the art as zeolite membranes and can be used as such. The present compositions, prepared on non-porous supports, are useful as sensors. Detailed Description of the Invention The present invention describes a new type of supported zeolite composition, formed on the surface of a growth-enhancing layer (GEL) containing nanocrystalline or colloidal size zeolites, mixtures of colloidal or nanocrystalline zeolites and metal oxides, mixtures of colloidal or nanocrystalline zeolites and colloidal-sized metals and mixtures of colloidal or nanocrystalline zeolites, colloidal-sized metals and metal oxide. Here, the growth-increasing layer and the zeolite layer that grows on it, contains zeolite, but each one is a different layer. The morphology of the zeolite layer is such that substantially no gaps extend through the thickness of the layer, because the crystals of similar tendency are oriented and grown on a polycrystalline dense mat. This dense mat, as used herein, means that at least 99%, preferably 99.9% of the crystals of the zeolite have at least one point between adjacent crystals, ie <; 20 k. In the present invention, the spacing between crystals is adjusted by a zone of grain boundary and the spacing of the zone of maximum grain limit, holes or defects absent, will be < 40A and such spacings can easily be observed by transmission electron microscopy and may contain inorganic oxide material. As used herein, a grain boundary zone is defined as the width of the disordered zone between two adjacent ordered crystals. Preferably, the zeolite layer will exhibit, in cross section, a set of oriented crystals of similar tendency, preferably a columnar morphology in cross section (see views (a) and (b) of Figure 4), formed by zeolite crystals. oriented crystallographically. Other tendencies are possible, depending on the particular type of zeolite and the composition of the synthesis mixture of the zeolite. The dense mat of the zeolite crystals grows internally in the composition, so the non-selective permeation paths through the membrane are blocked by the narrowest point of approach between crystals. Non-selective permeation paths are permeation paths that exist at room temperature that do not pass through the zeolite crystals. This blocking of the non-permeation paths exists at room temperature, after a model that occludes the pore structure is removed from the zeolite crystals. The models that are used to grow the zeolites are often removed by a calcination stage. From the research of transmission electron microscopy (TEM), the narrowest point of approach between crystals smaller than 20 Á after removing the model, can be established. The space between crystals at this point may contain the inorganic oxide material that restricts the non-selective permeation of the molecules through the membrane. The absence of non-selective permeation paths can be detected by the ability to prevent temperature permeation. environment (~ 20 ° -C) of dye molecules through the composition, after removing any model from the pore structure. The dye molecules, which can be selected to detect the non-selective permeation paths through the membrane, must have minimum dimensions that are larger than the control aperture through the zeolite and the size of the dye molecules must also Be younger than 20 Á. The non-selective trajectories carry dye molecules that are larger than the pore size of the zeolite. The dye molecules must be carried in a solution obtained by a solvent, which can be transported through the pore structure of the zeolite and the zeolite layer must not allow to collect foreign contaminants (such as water) before being tested. . It has been found that the compositions obtained according to the present invention block the permeation of dye molecules at room temperature through the zeolite layer. All chosen dye molecules will have at least one dimension less than about 20 Á. The lack of ambient temperature permeation of the dye molecules, with sizes less than about 20 k, demonstrates that the non-selective permeation paths with sizes less than about 20 k are blocked. It should be noted that this test does not have to be carried out with a dye molecule and that any molecular species can be used when it is smaller than 20 Á and larger than the pore size of the zeolite. The advantage of using a dye molecule is that it can be easily detected by optical means. The zeolite layer grows on top of a growth-enhancing mesoporous layer, layer (GEL) containing colloidal or nanocrystalline zeolites. the growth-enhancing layer smoothes the porous support, facilitates the growth of the zeolite layer and provides a seeding surface that allows control of the nucleation density of the zeolite crystals formed in the support. This growth-increasing layer must be chemically and mechanically stable in the hydrothermal synthesis conditions and the colloidal or nanocrystalline zeolites contained therein serve as nucleation sites for the growth of the zeolite layer. Altering the density of the nucleation sites alters the way the zeolite layer grows, which determines the size of the zeolite crystal, the packing (ie the gaps and defects) and the tendency of crystals or the external morphology of the zeolite. the crystals. The GEL layer contains particles identifiable with the interstices between the zeolite particles; zeolites and oxides of metal, zeolite and metal and zeolite of colloidal size, metal of colloidal size and metal oxide. These interstices are mesoporous and have sizes of about 20 to 2000 A, preferably about 40 to 200 K. Mesopores, as used herein, mean that there is a gap structure connected through the GEL layer. Interstices in this size range provide the permeation path for molecules through the GEL layer. The molecules can permeate through these interstices because they lack any material that would hinder mass transport during the use of the membrane. Applicants believe that the size and configuration of the zeolite crystals in the zeolite layer is controlled by the properties of the mesoporous layer (GEL that increases growth.) The control of the morphology, orientation and configuration of the crystals of Zeolite in the zeolite layer reduces the number of gaps between the crystals, because the crystals are packed together so that only the grain boundary zones will separate them (see Figures 4 (a), 4 (b) and 6). The GEL layer is believed to nucleate the formation of a dense mat of the zeolite crystals that grow on the surface of the GEL layer.This dense mat of crystals is closely packed together so that there is at least one point between adjacent crystals of < 20 A. As the zeolite layer grows from the interface in the GEL layer, the width of the crystals may increase, however, the individual crystals remain separated in their boundaries by at least one p spacing of < 20 A. This densely packed mat is the zeolite layer. The zeolite layers that grow without the use of the growth-increasing layer do not have the degree of perfection of the layers described herein. The zeolite layer of the present composition can be formed of crystals of a variety of tendencies (such as, for example, columns or plates, as determined by the SEM) or the preferred crystallographic orientation (as can be determined by the XRD). ), depending on the chosen zeolite, the reaction conditions of the synthesis mixture and the composition of the GEL. Hollow, as used herein, means the spaces between adjacent crystals of zeolite in the zeolite layer greater than 40 Á. The present compositions are virtually free of voids in the zeolite layer. The voids are at most about 1% by volume, preferably less than 0.1% by volume of the zeolite layer. The gaps can be detected from the cross-sectional images of the zeolite layer obtained in the scanning or transmission electron microscope. The defects are connected voids and spaces between the adjacent zeolite crystals, which extend through the thickness of the zeolite layer. In the present composition, the total number of defects in the zeolite layer with sizes > 40 k is < of 10,000 by 6.45 cm2, preferably from < 100 by 6.45 cm2. The number of defects greater than 2000 Á is less than 10 by 6.45 cm 2, preferably less than 1 by 6.45 cm 2. Isolated defects of the type described can be detected in the dye permeation experiments. The isolated spots in which the dye permeates the substrate reveals such defects. The defects can also be determined by examining the cross sections of the compositions of the zeolites in the scanning electron microscope. A cross-sectional view showing a zeolite composition which has no defect in the region examined is shown in Figure 4. Gas permeation can also be used to reveal defects in the composition. If the permeability of the zeolite layer to nitrogen at ambient temperature is less than 5 x 10 ~ 6 moles / (m2-sec-Pascal) for each miera and thickness of the zeolite layer, the composition will be considered as having an acceptable density of defects. More preferably, the permeability of the zeolite layer to nitrogen at room temperature is less than 5x10 ~ 7 moles (m2-sec-Pascal) for each thickness of the zeolite layer. The new architecture of the present invention is composed of a substrate, a growth-increasing layer containing mesoporous interstices and a layer of zeolite crystals. The substrate in which the GEL layer grows will be selected from porous and non-porous substrates. When a porous material is desired, it can be porous throughout its thickness. Preferably an inorganic oxide will be used. The porous substrate, here may be a ceramic, metal, zeolite, carbide, polymer or a mixture thereof. For example, alumina, titania, cordierite, mulita, stainless steel, Pyrex, silica, silicon carbide, carbon graphite and silicon nitride, or mixtures thereof, may be used. Preferably, a porous ceramic or porous metal, more preferably stainless steel, alumina and cordierite will be used. The porous substrate here may have a uniform pore size therethrough or it may be asymmetric, with a larger pore structure through the volume of the substrate with a smaller pore structure on the surface in which the GEL layer is going to grow The pore size of the substrate is dictated, among other things, by mass transfer considerations. It is preferred that the pore structure and the thickness of the substrate be chosen so that the resistance of the mass transfer does not limit the flow of the permeating material through the zeolite membrane during use. The porous substrate thus will exhibit a porosity of about 5 to 70%, preferably about 20 to 50% and an average pore size of about 0.004 to 2000 μm, preferably about 0.05 to 50 microns. It is preferred that the porous surface on which the GEL layer is deposited be smooth. The roughness in the substrate leads to defects in the zeolite layer. The substrate should have an average roughness with an amplitude of less than 20 μm with an aspect ratio of roughness of 1: 1. It is preferable that the average rugosity of the substrate is less than 0.5 μm with an aspect ratio of roughness less than 1: 1. One function of the GEL is to smooth the support. If a non-porous substrate is used, it may be selected from, for example, quartz, silicon, glass, borosilicate glass, dense ceramics, for example clay, metals, graphite polymers and their mixtures. When non-porous supports are used, the finished product can be used as a sensor or as a catalyst.

The growth-enhancing mesoporous layer is formed of a solution containing a nanocrystalline or colloidal zeolite or a mixture of metal oxide and a nanocrystalline or colloidal zeolite, or a mixture of nanocris-talin or colloidal zeolite and colloidal metal. Preferably, the nanocrystalline or colloidal zeolite or a mixture of nanocrystalline or colloidal zeolite and the metal oxide will be used to form a GEL layer. The metal oxides from which the GEL layer is prepared are colloidal metal oxides or polymeric metal oxides, prepared from the sol-gel process. The nanocrystalline zeolites are crystallites having a size of about 10 Á to 1 μm. Nanocrystalline zeolites can, for example, be prepared according to the methods set forth in PCT-EP92-02386, incorporated herein by reference, or other methods known to those skilled in the art. The particles of colloidal size are between 50 and 10,000 Á and form a stable dispersion or solution of discrete particles. Preferably, the colloidal particles will be from 250 to 5,000 A, more preferably less than 1000 k. Colloidal zeolites with sizes < 5000k can be easily obtained. The solution for preparing the GEL layer is coated on the surface of the porous substrate and calcined at temperatures < 10002C, preferably from about 200 to 1,000 ° C, more preferably from 300-600 ° -c. Following calcination, a stable mesoporous layer is formed which increases growth and remains in the final composition as a distinctive layer having a thickness of about 0.1 to 20 microns, preferably about 1 to 5 microns. This layer contains interstices, as described above. Following the calcination, the zeolite will be nanocrystalline or colloidal in size and the metal and metal oxide will be colloidal in size. The GEL layer can be formed of silica, silicates, aluminosilicates, aluminophosphates, silicoalumino-phosphates, metalloaluminifosfatos, metalloaluminofosfosilicatos and tin-silicates. Representatives of the molecular sieves (zeolites) that can be used include, but are not limited to, those of the structure type AFl, AEL, BEZ, EUO, FER, KFI, MAZ, MOR, MEL, MTW, OFF, TON, FAU (including zeolite X and zeolite Y), beta zeolite, LTA, LTL, AFS, AFY, APC, APD, MTN, MTT, AEL, CHA and MFI. Preferably an MFI zeolite with a ratio of silicon to aluminum greater than 30 will be used, which include compositions without aluminum. MFI zeolites with Si / Al ratios greater than 300 are referred to herein as silicalites. Some of the above materials, while they are not true zeolites, are frequently referred to in the literature as such and the term zeolite is used here broadly to include these materials. The metal oxides which may be used herein are selected from the group consisting of colloidal alumina, colloidal silica, colloidal zirconia, colloidal titania and polymeric metal oxides, prepared by the sol-gel process, and mixtures thereof. Preferably, the colloidal alumina will be used. Colloidal metals that can be used include copper, platinum and silver. By adjusting the ratio of the colloidal zeolite to the metal oxide, the density of the nucleation sites in the GEL can be controlled. This density controls the morphology of the zeolite film growing on the growth increasing layer in a subsequent hydrothermal synthesis step. The higher the nucleation density, the narrower the crystal width of the zeolite, which the crystals will exhibit at the interface of the zeolite layer. The nucleation density can be controlled by the relative proportions of the colloidal zeolites and the metal oxides (with the density decreasing as the amount of the metal oxide used increases) as well as the size of the colloidal zeolites in the GEL. Zeolites of colloidal size in the range of 50 to 10,000 k are thus used in the GEL. The larger the crystals of the colloidal zeolite used in the GEL, the wider the zeolite crystals in the layer. Applicants believe that the addition of the metal oxide, the colloidal metal or its mixtures to the colloidal zeolite in the GEL layer provides spaces between the nucleation sites that allow control of the width of crystals in the zeolite layer. GEL layers containing oxides of porous metal or colloidal metals fail to produce the necessary nucleation sites. The formulation of the GEL is 100-x% by weight of the colloidal metal or colloidal oxide; x% by weight of the colloidal zeolite, where x is at least 0.01, when the GEL is not formed from the pure colloidal zeolite. Here, the nucleation density is adjusted by the above formula as well as the particle size of the colloidal zeolite, the colloidal metal and the metal oxide. The smaller the particle size of the colloidal zeolite, the denser the nucleation sites that produce narrower zeolite crystals. The preferred synthesis technique used in this invention is the growth of the zeolite crystals on the face of a GEL layer that is oriented from 90 to 270 degrees in a low alkalinity synthesis mixture. In the 180 degree orientation, the preferred orientation, the GEL layer is horizontal and looks down, referred to here as inverted. Applicants believe that this prevents the zeolites, which form a core homogeneously in the synthesis mixture, from settling by gravity and incorporating into the growing columnar zeolite layer. Thus, the zeolite layer is not disturbed during the growth process.

We refer to this technique of synthesis as a process of crystallization In Situ Inverted of low alkalinity, that Increases the Growth (GEL-LAI-ISC). The growth MFI zeolite compositions are optically transparent through the thickness of the zeolite layer in which they do not disperse light within this layer. The zeolite compositions also show a significant crystallographic preferred orientation (as determined by the XRD). The preferred orientation will be different, depending on the zeolite chosen for the zeolite layer and the method of preparation. However, a preferred orientation will always be displayed. The crystallographic orientation of the MFI crystals in the preferred embodiment is such that at least 75% of the crystals in the zeolite layer are aligned in an orientation with the axis c parallel to the growth direction (within 152, preferably 5o of normal to the surface of the zeolite layer), preferably at least 90% of the crystals will exhibit the preferred orientation. The width of crystals in the zeolite layer can vary from 0.1 to 20 μm. A measure of the proportion of the crystals having a normal direction to the zeolite layer (such as axis c) can be obtained by comparing the X-ray diffraction pattern of the layer with that of a randomly oriented zeolite powder. In the case of an MFI type zeolite, for example, with a preferred orientation of the c axis, the ratio of the intensity of the peak 002 to the combined peak 200 and 020 is divided by the same ratio for the randomly oriented powder, the quotient is named the degree of the preferred crystallographic orientation (CPO - the orientation whose needs will be specified). Measured in this way, the layers, according to the invention, have a CPO degree of at least 2 and can have a degree of CPO along the c-axis, as high as 108. When preparing the GEL-coated substrate Upon which a zeolite layer will grow, the substrate is first coated with the GEL, followed by crystallization in situ. The GEL smoothes the porous substrate, facilitating the growth of the zeolite layer and provides a seeding surface to increase the nucleation density of the zeolite crystals formed on the GEL. This gel must be stable chemically and mechanically under the hydrothermal conditions employed during the preparation of the final composition and also capable of increasing heterogeneous nucleation or surface nucleation. By altering the density of the nucleation sites, the tendency of the zeolite crystals changes, adjusting the width of the crystals formed. The GEL layer is produced from solutions prepared by a variety of solution coating techniques, known in the art. For example, immersion coating, rotary coating and sliding molding can be used. The coated substrate is then calcined at temperatures ranging from about 200 to 1000 ° C to form a stable mesoporous hue. The preferred method of coating is determined from the geometry of the substrate. In practical situations, a rotary coating method for discs or plates can be used. This rotating coating gives excellent control of the thickness of the coating. For tubular and honeycomb structures, an immersion process can be used. The GEL will be approximately 0.1 to 20 μm thick. The calcination time will be sufficient to form a mechanically stable layer in at least about 30 minutes, preferably 2 hours, more preferably at least about 6 hours. The calcination of the GEL will typically be conducted at a heating rate of about 10 to 20 ° C / hour, from room temperature to the calcination temperature, this is readily determined in the art. Preferably, a dilute solution of a concentration of 0.1 to 10% by weight solids, more preferably 1% by weight solids, will be used to produce the GEL. The GEL coating solution may contain small amounts of organic binders, such as PEG (polyethylene glycol), PVA (polyvinyl alcohol) or methyl cellulose. Once the substrate, which has the GEL coating, is prepared, the zeolite layer begins to grow. The hydrothermal treatment for forming the upper layer of crystalline zeolite is carried out by contacting the substrate carrying the intermediate layer with a synthesis mixture of the zeolite and treating hydrothermally for a time and a temperature sufficient to effect the crystallization, for example in an autoclave under autogenous pressure. Heating times can be, for example, within the range of 30 minutes to about 300 hours. The temperatures can be, for example, from 50 to 300 ° C, approximately, and preferably around 180 ° C. The growth of the zeolite layer on the GEL-coated substrate is carried out with the GEL layer in an orientation and location in the synthesis mixture, so that the sedimentation of the particles produced during the synthesis is minimized or prevented. hydrothermal treatment on the GEL layer. For example, the GEL layer is advantageously at least 5 mm and preferably at least 8 mm, from a wall or especially the base of the container, to avoid interference from particle sedimentation. Alternatively, an additional element to inhibit sedimentation can be employed in the synthesis process of the zeolite.

The zeolite layer may have any of a preferred orientation in the configuration a crystallographically preferred orientation, or both. The preferred orientations in configuration or crystallographic occur due to the control of the relative regimes of nucleation and growth offered by the synthesis procedure. Specifically, during the synthesis, the growth regime can be made to dominate the regimen of surface nucleation of new crystals or the incorporation of new crystals. The incorporation of new crystals is defined as the union on the surface of the growth layer of a crystal formed in the synthesis mixture. Since the growth regime dominates the renucleation or incorporation, crystals can grow competitively for extended periods of time without the significant addition of new crystals in the growth layer. Since the growth layer is composed of individual crystals and the synthesis method seeks to prevent renucleation or incorporation of crystals, the resulting composition may have a preferred configuration orientation or crystallographically, or both, the configuration orientation occurs because the crystals are forced to grow with preferred regular tendencies (or morphology) on the surface of the zeolite layer. A regular trend (or morphology) is taken as a regularly configured profile of a particular crystallographic grain in the layer. The regularly configured profiles are defined as those that can be equipped or packed together so that there are no interconnected spaces or gaps between the crystals. The interconnected gaps will form a structure of pores. A few examples of regular habits or tendencies with regular configurations are columnar, cubic, rectangular and prismatic. Spherical, irregular and elliptical configurations are not considered to be regular trends. In a preferred configuration orientation, the defined layers will have the same regular trend. This can be measured by unfolding or fracturing the substrate on which the layer grows and examining the cross-sectional morphology of the zeolite layer with a scanning electron microscope. By examining the surface of the zeolite layer as it grows, it can also give additional information relative to the preferred configuration orientation in the layer. A layer with a preferred orientation in configuration is taken as one which has more than 90% of the crystals within a layer within the zeolite layer exhibiting similar regular tendencies of its own. The self-similar requirement means that the same regular trend is exhibited within a layer and that it can be drawn on the electron micrograph of the cross section of the zeolite layer, however, although the configurations are the same, they do not have to be the same size. Due to the growth mechanism of the zeolite layer, it is possible to have a preferred configuration orientation in the bottom (base) of the layer and another preferred configuration orientation in a layer near the surface of the first layer. An example of this is a MFI zeolite layer, which has a columnar tendency at the base of the layer and a rectangular tendency at the surface of the layer. Many layers of MFI zeolite that grow in accordance with the present invention exhibit only a tendency through the thickness of the zeolite layer. Usually, the MFI zeolite layers with a preferred C-axis orientation exhibit a columnar tendency (or morphology) throughout the thickness of the zeolite layer. Often the preferred orientation layers have a preferred crystallographic orientation. In the preferred embodiment, the zeolite layer grows by suspending a substrate having the growth-increasing layer coated, in a synthesis mixture of the zeolite, with the substrate oriented so that the growth-increasing layer is oriented from 90 to 80%. 2702 in the synthesis mixture and in which this orientation of 180 of the growth-increasing layer is horizontal and looks down, and where the growth-increasing layer is at least about 5 mm from the bottom, at the lowest point, of the synthesis mixture of the zeolite, hydrothermally treating the substrate containing the synthesis mixture of the zeolite for a time and at a temperature sufficient to form the zeolite layer. For example, at about 50 to 300 ° C, preferably about 100 to 250 ° C for at least about 30 minutes, to form the zeolite layer on the growth-increasing layer. Washing the GEL and the substrate coated with zeolite with water, for a time and at a temperature sufficient to remove any unreacted zeolite synthesis mixture, preferably at a temperature of about 15 to 100 ° C, for at least about 10 minutes, more preferably for at least six hours. When the zeolite synthesis mixture contains an organic model, the composition, after washing, is calcined at a temperature of about 400 to 600 ° C for at least one hour. Larger roasting times will not affect the performance of the membrane. The zeolite layer growing according to the present invention will have a thickness of about 0.1 to 100 μ, preferably 0.5 to 20 microns. The thicknesses here are defined as the distance from the interface of the zeolite GEL layer to the extreme top point in the zeolite crystal. The zeolite layers of the present invention are prepared from the zeolite synthesis mixtures. Such mixtures are any from which the zeolite crystals grow and are known in the art (see, for example, the Handbook of Molecular Sieves, by Rosemarie Szostak, Van Nostrand Reinhold, NY 1992, Zeolite Molecular Sieves, D. W. Breck; R. E. Kreiger Publishing Co., Malaba, Florida, 1984 ISBN 0-89874-648-5.) The zeolites that can be used include those that are used in the GEL layer. A preferred route of the MFI zeolites is a low alkalinity synthesis mixture having a pH of 8 to 12, preferably 9.5 to 11, and from which the MFI zeolite crystals can grow. Such mixtures are easily prepared by those skilled in the art. For example, suitable mixtures include Na 2? TPABr (tetrapropylammonium bromide), SiO 2 and water. The membranes grow by suspending the porous substrate coated with selection GEL in the low alkalinity synthesis mixture. This synthesis mixture is then heated to about 50 to 300 ° C, preferably to about 180 ° C, for a period of about 30 minutes, preferably from about 30 minutes to about 300 hours. The zeolite layer of the present invention will preferably grow in the growth-increasing layer, oriented from 90 to 2702. Any growth on a substrate that does not have the GEL layer, can be easily removed by known techniques, such as shaving or frosting , which is not part of this invention.

Once the zeolite layer has grown, any remaining synthesis mixture is removed, for example by washing with water at a temperature of about 15 to 100 ° C, preferably about 80 to 100 ° C for at least about 10 minutes, preferably at least six hours . Excessive washing for long periods will not affect the separation capabilities of the compositions. Once the synthesis mixture of the zeolite has been removed, if it contains an organic model, the composition is burned to remove the model. For example, calcination in air or oxygen at about 400 to 600 ° C can be used for at least one hour. Longer calcination times will not affect the performance of the membrane. If an organic model is not present, a drying step at temperatures of about 100 ° C may optionally be carried out. Catalytic functions can be incorporated into the compositions by methods known in the art. When a catalytic function is incorporated, this composition can be used as an active element in a reactor. Several different architectures of the reactor can be constructed, depending on the location of the catalytic site in the composition. In one case of the catalytic function that can be placed inside the zeolite layer, while in another case the catalytic function can be placed inside the support or the GEL layer and in another case the catalytic function will be distributed through the support , the GEL layer and the zeolite layer. In addition, the catalytic function can be incorporated into a reactor by placing conventional catalyst particles near one or more surfaces of the composition, so that specific products or reagents are continuously and selectively removed or added to the reaction zone through the reactor. Impregnation with catalytically active metals, such as the noble metals of Group VIII and particularly platinum, can impart a catalytic function to the composition. The catalytic activity can be incorporated by techniques known to those skilled in the art as an incipient wetting technique. The amount of the noble metal of Group VIII to be incorporated is within the range of 0.1 to 10% by weight. The compositions are useful for separation processes, whereby a filler material, derived from petroleum, natural gas, hydrocarbons or air, comprising at least two molecular species, is contacted with the composition of the invention, wherein less one molecular species of the filler material is separated therefrom by the composition and where the hydrocarbon fillers are the carbon, bitumen and filler materials derived from the kerogen. The separations that can be carried out using a composition according to the invention include, for example, the separation of normal alkanes from similar boiling hydrocarbons, especially nC ^ or C ^ g alkanes from kerosene, normal alkanes and alkenes from corresponding branched isomers of alkanes and alkenes; the separation of aromatic compounds from each other, especially the separation of Cs aromatic isomers from each other, more especially para-xylene, from a mixture of xylenes and, optionally, ethylbenzene, and the separation of aromatics from different numbers of carbon, for example mixtures of benzene, toluene and aromatic Cgmixtos, separation of aromatic compounds from aliphatic compounds, especially aromatic molecules with from 6 to 8 carbon atoms of aliphatic C5 - Clo (range naphthas), separation of olefinic compounds from saturated compounds, especially light alkenes mixtures of alkanes / alkenes, more especially ethene ethane and propane propene; remove hydrogen from cnts that contain it, especially from light cnts from refineries and petrochemical gas, more especially from C2 and lighter components, and alcohols from aqueous streams. Also alcohols derived from other hydrocarbons, particularly alkanes and alkenes, which may be present in mixtures formed during the manufacture of the alcohols. Specifically, the following table shows some possible cargo materials derived from petroleum, natural gas, hydrocarbons or air and the molecular species separated from them, by the use of the present compositions. The table does not mean any limitation.

Applicants believe that molecular diffusion is responsible for the above separations. Additionally, the compositions can be used to effect a chemical reaction to supply at least one reaction product by contacting the fillers, as described above, or in the following, with the compositions having a catalyst incorporated within the zeolite layer, support or intermediate layer, placing the catalyst in proximity sufficiently close to the composition to form a module. A module will react with the loading material just before its entry into the composition or just after its exit from the composition. In this way, one can separate at least one reaction product or reagent from the fillers. The selection catalysts for fluids of a particular process are well known to those skilled in the art and are easily incorporated into the present compositions or formed in modules by a person skilled in the art. The following table represents some of the possible load materials / processes, in addition to those above, that can be reacted, and some possible product supplied. The table does not mean any limitations The zeolite layer of the invention can be used as a membrane in such separations without the problem of being damaged by contact with the materials to be separated. Also, many of these separations are carried out at elevated temperatures, as high as 5002C, and it is an advantage of the supported zeolite layer of the present invention that it can be used at such high temperatures. The present invention therefore also supplies a process for the separation of a fluid mixture, which comprises contacting the mixture with one face of the zeolite layer, according to the invention, under such conditions that at least one component of the mixture has a different permeability in stable state, through the layer, from that of another component, and recover a component or mixture of components from the other face of the layer. The invention further provides a process for catalyzing a chemical reaction, which comprises contacting a charge material with a zeolite layer, according to the invention, which is in active catalytic form under the conditions of catalytic conversion, and recovering a composition comprising at least one conversion product. The invention further provides a process for catalyzing a chemical reaction, which comprises contacting a filler with one each of a zeolite layer, according to the invention, ie in active catalytic form, under the conditions of catalytic conversion. , and recovering from the opposite face of the layer at least one conversion product, advantageously at a concentration different from its equilibrium concentration in the reaction mixture. For example, a p-xylene rich mixture of the reactor or a reactor product in a process of isomerization of xylenes, aliphatic aromatics and hydrogen in a reforming reactor, hydrogen removal from refinery processes and chemicals, such as the dehydrogenation of alkane, in the formation of alkenes, dihydrocyclization of light alkane / alkenes in the formation of aromatics (for example Cyclar), dehydrogenation of ethylbenzene to styrene. The invention further provides a process for catalyzing a chemical reaction, which comprises contacting a reagent of a bimolecular reaction with a face of a zeolite layer, according to the invention, ie in an active catalytic form, under conditions of catalytic conversion, and control the addition of a second reagent by diffusion of the opposite face of the layer, in order to more precisely control the reaction conditions. Examples include: controlling the addition of ethylene, propylene or hydrogen to benzene, in the formation of ethylbenzene, eumeno or cyclohexane, respectively. The invention further considers the separation of a filler material, as described herein, wherein the separated species react as they leave the composition or as they pass through the composition and thus form another product. This is believed to increase the impulse force for diffusion through the membrane layer. Some specific reaction systems, where these compositions will be advantageous for selective separation in the reactor or in a reactor effluent, include: the selective removal of a para-xylene-rich mixture from the reactor, the product of the reactor, the reactor charge or other locations in a process of isomerization of xylenes, the selective separation of aromatic fractions or streams rich in aromatic molecules specific to catalytic reforming or other aromatic generation processes, such as the processes of dehydrocyclization of alkanes and light alkenes (for example C3-C7 paraffins to aromatics, from processes such as Cyclar), petrol methanol processes and catalytic thermal decomposition, selective separation of benzene-rich fractions from streams and refinery processes and from chemical plants; Selective separation of olefins or olefin specific fractions from refinery process units and chemical products, including catalytic and thermal decomposition, olefin isomerization processes, methanol to olefin processes, naphtha to olefin conversion processes, dehydrogenation of alkanes, such as the dehydrogenation of propane to propylene, selective removal of hydrogen from streams and refinery and chemical processes, such as catalytic reforming, dehydrogenation of alkanes, catalytic decomposition, thermal decomposition, dehydrocyclization of light alkanes / alkenes, dehydroge -nation of ethylbenzene, dehydrogenation of paraffins; selective separation of molecular isomers in processes such as isomerization of butane, isomerization of paraffins, isomerization of olefins, selective separation of alcohols from aqueous streams and / or other hydrocarbons. The following examples are for illustration and do not mean any limitations. EXAMPLES Materials The following reagents were used in the preparation of the GEL coatings: colloidal alumina solution, colloidal titania prepared from a sol-gel process, colloidal silicalite solutions, and distilled water. Various batches of the colloidal silicalite solutions, prepared according to the patent PCT-EP92-02386, were used for the preparation of the GEL coatings. More information on these solutions is shown below: Silicalite < MFI) Observations: 1. All suspensions were prepared from the same type of synthesis solutions with the same raw material. 2. Lot 4 was a duplication of 2. The solids content of lots 2 and 4 was calculated assuming a 55% conversion of the amorphous silica to the zeolite. The actual solids content of these 2 unwashed samples is, of course, higher, for example for the 4 solids content (evaporation to dryness) was 23.3% by weight, but this includes zeolite, amorphous silica and TPAOH- Residual NaOH. Porous alumina and stainless steel substrates were used to support the GEL and zeolite coatings. The average pore size and porosity of the alumina is approximately 800 Á and 32%, respectively. The sintered, porous, stainless steel substrates of Mott (0.25 μm) and Pall (M020, 2 μm) were obtained. All substrates were cleaned with acetone in an ultra-sonic bath, dried at 120 ° C and then cooled to room temperature before use. GEL Coating In general, a dilute solution is preferred to produce a high-quality growth-enhancing layer. Dilution with distilled water to obtain a solids concentration of less than 1% by weight is generally preferred. The colloidal silicalites and metal oxides were first diluted separately with distilled water at a concentration of 0.5% by weight. The colloidal silicalite solution was slowly added to the desired amount of the metal oxide solution with continuous stirring. The resulting solutions with the desired weight% of colloidal silicalite and metal oxide were then degassed for 15 minutes to remove trapped air in the solutions. The substrates were then coated by rotation with these solutions, at 4000 rpm, and calcined at 400-500 C for 6 hours in the air. The heating regime was controlled at 202 C / hour.

Hydrothermal Reaction Hydrothermal experiments were performed using mixtures of the following reagents: NaOH (Baker), A1 (N03) 3.9H20 (Baker), Ludox AS-40 (Dupont), NalCoag 225.2328 tetrapropylammonium bromide (98%, Aldrich) , and distilled water. MFI membranes were prepared from two different mixtures of reaction batches, one containing silica only, to make an MFI with high silica content, and the other with added alumina, to obtain the ZSM-5. They have the general formulation xM20: 10 Si02: z Al203: p TPABR: yH20; M can be Na, Li, K, Rb and Cs, x varies from 0 to 5, and varies from 50 to 30,000, z varies from 0 to 0.5 and p varies from 0.2 to 1. All the results shown in the next section have the composition of 0.22 Na2 ?: 20 SÍO2: O AI2O3: 280 H2O: 0.5 TPABr with the exception of sample ZSM-5, which contains 0.05 AI2O3 for sample ZSM-5. The 1.74 g of TPABr and 0.45 g of NaOH (50% by weight) were dissolved in 52 ml of distilled water, with stirring. To this solution, then 18.8 g of Ludox AS-40 was added with stirring, for at least 15 minutes, until a uniform solution formed, The TPABr can be replaced with the tetrapropylammonium hydroxide, if desired. The substrates with the GEL coating were placed inverted (orientation of 1802) in a Teflon-lined autoclave, supported on the stainless steel wire frame. The distance between the substrate and the bottom of the autoclave was at least 5 mm. The synthesis solution is then emptied into the autoclave to cover the entire substrate. The autoclave was sealed and placed in an oven, which was previously heated to the desired temperature. The autoclaves were removed from the oven after the reaction and cooled to room temperature. The coated substrates were washed with hot water for at least 6 hours, then calcined at 500 ° C for 6 hours in the air. The heating rate was controlled at 102c / hour. Analysis The resulting membranes were characterized by X-ray diffraction, electron microscopy, dye test and permeability evaluations. Results and Discussion Products The following table shows some of the typical examples synthesized under different experimental conditions, such as the GEL composition, the reaction time and the substrate.

CPO = preferred crystallographic orientation. § alumina: pore size of 0.08 μm; SS = stainless steel, Pall Corporation, PMM Grade M020 # a. 100% by weight of unwashed solution (lot 2) b. 100% by weight of the washed solution (lot 1) c. 50% by weight of washed solution (lot 1); 50% by weight of alumina d. 50% by weight of unwashed solution (lot 2); 50% by weight of alumina e. 10% by weight of unwashed solution (lot 4); 90% by weight of alumina f. 100% by weight of the washed solution (lot 3) * 25% more water was used in the synthesis solution § axis b is the major phase.

General Observations The X-ray diffraction pattern of the inverted zeolite membrane, grown on a substrate coated with GEL (LAI-GEL-ISC) was observed. The reflections of the MFI type zeolite are identified in all the diagrams. No second phase of zeolite was observed. The only lines in the patterns not associated with the zeolite identified with the porous support. The pattern associated with the GEL-LAI-ISC membrane was drastically different from that of the MFI powder. It is seen (Figures 1 and 2) that the prepared MFI crystal layer of GE1-LAI-ISC exhibited a pronounced crest at 001, with no other significant crests of zeolite occurring in the pattern or (crests (oko) (see Figure 3) This is strong evidence that the preferred orientation of directions (0 0 1) or (oko) parallel to the direction of growth exists in the membrane.Another way of saying this is that the MFI crystal layer in the membranes GEL-LAI-ISC showed a very strong crystallographic orientation with the c-axis normal to the GEL layer Figure 5 shows a plan view of a typical membrane (C-axis orientation) GEL-LAI-ISC (sample # 2) The tightly packed upper surface and the columnar tendency in cross-section of the crystals was observed for the zeolite layer, Figure 4a shows the zeolite layer (C), the growth-increasing layer (B) and the porous support ( A) The main part of Figure 4a showed continuous growth of the zeolite that completely covers the surface of the GEL layer. The formation of a dense packing of the columnar crystals in the zeolite layer is evident. The width of the right columns in the layer that increases growth is very narrow and becomes larger and larger as the layer grows. As such, the cross-sectional area of the grains grows upwards in the layer, the columnar nature of the microstructure is consistent with the X-ray pattern of the powder diffraction. In Figure 5 it is clear that the zeolite surface consists of a continuous array of densely packed zeolite crystals, which are < 10 μm in width. Effect of Density of Nucleation Sites on the Width of MFI Crystals The width of the columns of zeolite crystals in sample # 5 is less than that of sample # 6, which has a lower density of nucleation sites in its GEL, due to the addition of colloidal alumina. Morphology was similar, but grain size is larger in sample # 6 than in sample # 5. Thus, by simply controlling the nucleation density, the width of the zeolite crystals in the zeolite layer can be modified and controlled. Effect of the Substrates Used in the Morphology of the MFI Crystals The sample # 9 that grows on stainless steel as a substrate, is very similar in morphology to the membrane made on an alumina substrate. The formation of MFI crystals seems independent of the substrate used. Dye Permeation Test The absence of defects in the zeolite layer MFI was measured for its lack of ability to pass dye molecules into the porous substrate. Any dye which penetrates the substrate is easily visible due to a change of color in the substrate. Rhodamine B (0.5% by weight) in methanol was added to the center of a dry membrane to cover the surface. Approximately 2 to 3 drops were applied to a 2.54 cm membrane and allowed to dry for -30 seconds before clearing excess dye. The methanol was then dried on the membrane to remove any excess of the Rhodamine B solution on the membrane. The membrane was then washed with methanol for 10-30 secondsAny permeation of the dye into the substrate through the defects in the membrane is then easily apparent. The methanol penetrated into the substrate, however, no dye of Rhodamine B was observed on the substrate, which indicates that the membrane is capable of performing the separation of the dye. When the membrane was synthesized from a zeolite synthesis mixture, which contains an organic model, the dye test was performed after calcination. If a non-ceramic substrate is used, other methods are used in addition to visual examination to detect penetration into the membrane.

Claims (40)

1. CLAIMS 1. A composition comprising a substrate, having coated thereon a mesoporous growth-increasing layer and a layer of zeolite crystals on this mesoporous growth-enhancing layer, wherein said mesoporous growth-increasing layer comprises zeolites; zeolite and metal oxide; zeolite and metals of colloidal size; zeolite, metals of colloidal size and metal oxide; and their mixtures, and in that the zeolites are selected from the group consisting of the nanocrystalline zeolites and the colloidal size zeolites, and where the mesoporous layer which increases growth has interstices of about 20 to 2000 k and the zeolite layer is a layer polycrystalline 2. A composition, according to claim 1, wherein 99% of the zeolite crystals have at least one point between adjacent crystals, ie < 20 k. 3. A composition, according to claim 1, wherein the substrate is a porous substrate, selected from the group consisting of stainless steel, Pyrex, ceramics, alumina, titania, cordierite, mulita, silicon carbide, silicon nitride, carbon, graphite, zeolite and their mixtures. 4. A composition, according to claim 3, wherein the substrate is a porous substrate having a porosity of about 10 to 70% and a pore size distribution of about 0.004 to 100 μm. 5. A composition, according to claim 1, wherein the growth-increasing layer is approximately 0.1 to 20 μm thick. 6. A composition, according to claim 1, in which the zeolite crystals of the zeolite layer and the zeolite of the growth-increasing layer are selected from the group consisting of: silica, silicates, aluminosilicates, aluminophosphates, silicoaluminum-phosphates, metal-aluminum-phosphates, metal-aluminum-phospho-silicates and stannosilicates. A composition, according to claim 6, wherein the zeolite crystals of the zeolite layer and the zeolites of the growth-increasing layer are selected from those of the structure of the zeolite X, Y zeolite, zeolite type. Beta, MFI zeolite, silicalite, LTA, LTL, CHA, AFL, AEL, BEA, EUO, FER, KFI, MAZ, MOR, MEL, MTW, OFF, TON, FAU, AFS, AFY, APC, APD, MTN, MTT , AEL, and their mixtures. 8. A composition, according to claim 1, wherein the metal oxide and the growth-increasing layer are selected from the group consisting of colloidal-sized alumina, silica, titania, zirconia, and mixtures thereof. 9. A composition, according to claim 1, wherein the colloidal sized metal is selected from the group consisting of copper, platinum, silver and mixtures thereof. 10. A composition, according to claim 1, wherein the composition has < 1% in volume of holes. 11. A composition, according to claim 10, wherein the composition has less than 0.1% by volume of voids. 12. A composition, according to claim 1, wherein the composition has < 10,000 defects per 6.45 cm2 of > 40 Á. 13. A composition, according to claim 1, wherein the zeolite crystals of the zeolite layer are from about 0.1 to 20 μm wide and about 1 to 100 μm thick. A composition, according to claim 1, wherein the nanocrystalline zeolites in the growth-increasing layer are from about 10 Á to 1 μm in size, and the colloidal-sized zeolites in the growth-enhancing layer are from about 50 Á to 1 μm. 15. A composition, according to claim 1, wherein the zeolite crystals of the zeolite layer exhibit in cross section a set of crystals of similar tendencies. 16. A composition, according to claim 1, in which the metal oxide and the metal of a colloidal size are present in an amount of 99.99% by weight to approximately 0.01% by weight. A composition, according to claim 1, wherein the zeolite crystals are of the MFI structure type and exhibit an orientation of the C axis within 15 degrees of normal to the surface of the zeolite layer or the orientation of the axis or a mixture thereof, and in that this orientation of the C-axis the zeolite crystals are columnar. 18. A composition, according to claim 4, wherein the porous substrate has an average roughness with an amplitude of <; 10 μm, with an aspect ratio of the roughness < 1: 1 19. A composition, according to claim 1, wherein the substrate is a non-porous substrate, selected from the group consisting of quartz, silicon, glass, borosilicate glass, clay, metal, polymer, graphite, dense ceramics, and its mixtures 20. A composition, according to claim 1, wherein the zeolite crystals with columns. 21. A process for preparing a composition, which comprises the steps of: (a) coating a substrate with a growth-increasing layer, in which this growth-increasing layer is prepared using a solution comprising zeolite; zeolite and metal oxide; zeolite and colloidal metal, or zeolite, colloidal metal and metal oxide; or their mixtures; and wherein said zeolite is selected from the group consisting of the nanocrystalline zeolite and colloidal zeolite and wherein the metal oxide is a metal or solide metal oxide, prepared by the sol-gel process, followed by the salsination; (b) putting on substrate the substrate, which has a sap that increases growth, coated with a zeolite synthesis mixture; (c) hydrothermally treating the synthesis mixture of the zeolite for a time and at a temperature sufficient to form the zeolite sap on the sap which increases the sressation, and in which the sedimentation of the particles produced from the mixture is prevented. synthesis of the zeolite, during the hydrothermal treatment, on the zeolite layer; (d) removing the synthesis mixture from the zeolite without reacting. 22. A process for preparing a composition, according to claim 21, wherein the step (a) of re-surfacing is preferably carried by submerging the substrate with the substrate is a tubular or honeycomb substrate, and rotatingly resurfacing the substrate with this Substrate is a substratum of disso or plasa. 23. A proseso, of agreement are the reivindisasión 21, in which the solusión to prepare the sapa that increases the sresimiento is a solusión that has a sonsentrasión of 0.1 to 10% in weight of solids. 24. A proseso, of agreement are the reivindisasión 21, which also comprises calsinar the somposision at a temperature of approximately 400 to 6002C, for at least about an hour, suando the mixture of synthesis of the zeolite are an organism model. 25. A proseso, of agreement are the reivindisasión 21, in which, during the stage (b) of sontasto, the substrate is oriented so that the sapa that increases the sresimiento is oriented from 90 to 2702, in the mixture of synthesis, and in which the 1802 orienteering of the sapa that increases sresimiento is horizontal and looks downward and this sapa that increases growth is at least about 5 mm from the bottom of the alkaline synthesis mixture. 26. A proseso, of agreement are the reivindisasión 21, in which the stage (d) somprende wash are a solusión that somprende water. 27. A zeolite membrane, according to claim 1, in which the somposisance is insorporated about 0.1 to 10% by weight of a noble metal of Group VIII. 28. A proseso, of agreement are the reivindisasión 21, in which the ansho of the crystals in the sap of zeolite is increased by the increase of the sanctity of the metal soloidal or the oxide of metal in stage (b). 29. A process of separation, the sual somprende put in sontasto a material of twill, derived from oil, air, hydrosarburos or natural gas, which includes at least two thickened thickeners, is a somposisión that somprende a substrate that has re-covered a sapa mesoporosa that increases the sresimiento, and a sapa of zeolite crystals on this mesoporous sapa that increases the sresimiento, and in that disha sapa mesoporosa that increases the sresimiento som-prende zeolitas; zeolite and metal oxide; zeolite and metals of solitary size; zeolite, metal of solitary size and metal oxide; and their mixtures, and in which the zeolites are seleded from the group consisting of nanocrystalline zeolites and zeolites of solitary size, and where the mesoporous sap that increases the sressation has interstices of about 20 to 2000 A and the sap of zeolite is a polysrystalline sap. . 30. A proseso, of agreement are the reivindisasión 19, in which the moles thickeners are separated by means of diffusion. 31. A proseso, of agreement are the reivindisasión 29, in which the twill material is selessiona of the group that are of mixed xylenes and ethylbenseno; hydrogen, H2S and ammonia; mixtures of n-butanes and isobutanes; mixtures of n-butenes and isobutenes; normal paraffins that are kerosene; mixtures of nitrogen and oxygen; mixtures of hydrogen and methane; mixtures of hydrogen, ethane and ethylene, mixtures of hydrogen, propane and propylene, naphtha of the soquifisator which are normal olefins C5 to C ^ Q and paraffins; methane and ethane mixtures that are argon, helium, neon or nitrogen; intermediate produtos of the reformer satalitiso del reastor; fluid produtos of desomposicion satalítisa,; naphtha, light soda gas oil; mixtures of n-pentanes and isopentanes; mixtures of n-pentenes and isopentenes; mixtures of ammonia, hydrogen and nitrogen; aromatherapy mixtures of 10 butenes sarbons, mixtures of sulfur and nitrogen mixtures, mixtures of sulfur compounds, mixtures of nitrogen compounds, mixtures containing bensen, and mixtures thereof. 32. A process to sabotage a quiescent reassumption, the sual somprende to put in sontasto a sorrent of reassión are a somposision that somprende a substratum that has resubierta a sapa mesoporosa that increases the sresimiento and a sapa of sristales of zeolite on the sapa mesoporosa that increases the sresimiento , and in that this mesoporous sapa that increases the sresimiento somprende zeolites; zeolite and metal oxide, zeolite and metals of solitary size; zeolite, metal of solitary size and metal oxide; and their mixtures, and in which the zeolites are seleded from the group consisting of nano-crystalline zeolites and zeolites of single-size, and mesoporous disha sapa which increases the sressation has interstices of about 20 to 2000 A and the zeolite sap is a polysrystalline sap. 33. A Proseso, of agreement are the vindication 29, in which the satalizer forms a module is the somposission or is contained within the somposission. 34. A proseso, of agreement are the vindication 33, in which the twill material is oversized of mixed xylenes and ethylbensen; ethane, ethylbensen, butanes; propane; normal paraffins C ^ g- 18 'H2S' sorrientes of satalitisa reformation, light petroleum gases; sulfur and nitrogen blankets; Sulfur compounds, nitrogen blankets; mixed butenes; and their mezslas. 35. A proseso, of agreement are the reivindisasión 34, in which suando the material of sarga reassiona are the somposisión, a reastivo or a produsto of reassión is obtained. 36. A proseso, of agreement are the reivindisasión 29, in which the twill material is oversized of mixed xylenes and ethylbensen; ethane, ethylbensen, butanes; propane; normal paraffins ^ Q- C ^ g; H2S; sorrientes of satalitisa reformation; light petroleum gases (LPG); sulfur; nitrogen compounds, mixed butenes, and their mixtures. 37. A somposission, the sual can be obtained by the process of claim 21. 38. A somposition, according to claim 1, wherein the zeolite layer exhibits a preferred orientation of the configuration, a preferred orientation, or a mezsela of the two orientsiones. 39. A process to sate a chemise reassumption, sual is to put in sontasto a reastive of a bi-oral reassumption mezsla with a face of a composition that shadows a substratum that has a mesoporous sapa that increases the sresimiento and a sapa of crystals. of zeolite on this mesoporous sapa that increases the sresimiento, and in that the mesoporosa sapa that increases the sresimiento somprende zeolites; zeolite and metal oxide; zeolite and metals of solitary size, zeolite, metal of solitary size and metal oxide; and its mixtures, and in which the zeolites are selesionated from the group that grows from the nanocrystalline zeolites and zeolites of single-size and the mesoporous sapa which increases the sressation has interstisions from about 20 to 2000 Á and where the sap of zeolite is polysrystalline, is desir in astute satalitisa form, under the sonsions of satalitisa sonversion, and sontrolar the adisión of a second reastivo by the diffusion from the opposite sara of the estrustura. 40. A proseso, of agreement are the reivindisasión 29, in which the somposission adsorbs at least one thickened thickener of the twill material.