Abstract: A synthetic porous crystalline material has the structure of ZSM-5 and a composition involving the molar relationship:

Abstract: A highly selective process is described for preparing 2,6-dimethylnaphthalene which comprises reacting a naphthalene hydrocarbon selected from naphthalene, methylnaphthalenes, dimethylnaphthalenes, trimethylnaphthalenes, polymethylnaphthalenes or their mixtures with one or more benzene hydrocarbons selected from benzene, toluene, xylenes, trimethylbenzenes, tetramethylbenzenes, pentamethylbenzene and/or hexamethylbenzene, under at least partially liquid phase conditions, in the presence of a zeolite belonging to the structural type MTW and optionally in the presence of a methylating agent.

Abstract: A process for hydrotreating a hydrocarbon feed, comprising subjecting said feed to hydrotreating conditions in the presence of a catalyst comprising an essentially alumina-based extruded support, essentially constituted by a plurality of juxtaposed agglomerates, optionally at least one catalytic metal or a compound of a catalytic metal from group VIB (group 6 of the new periodic table notation) and/or optionally, at least one catalytic metal or a compound of a catalytic metal from group VIII (group 8, 9 and 10 of the new periodic table notation), in which the sum S of the group VIB and VIII metals, expressed as the oxides, is 0% to 50% by weight, and wherein each of these agglomerates is partly in the form of packs of flakes and partly in the form of needles, said needles being uniformly dispersed both about the packs of flakes and between the flakes, in which the alumina agglomerates are obtained by forming a starting alumina originating from rapid dehydration of hydrargillite and in which the amount of alum

Abstract: For isomerising aromatic compounds containing eight carbon atoms in the presence of hydrogen, a mixture containing compounds with a boiling point of about 80° C. to 135° C. comprising at least one paraffin containing eight carbon atoms, at least one naphthene containing eight carbon atoms, at least benzene and at least toluene is added to the feed before introducing it into the isomerisation reactor R via line 1. These additions are made by a recycle via line 6 or by adding fresh compounds via line 11, or be a combination of fresh and recycled compounds via lines 6 and 11. Hydrogen is added via line 15.

Abstract: The present invention relates to a method of preparing 2,6-dimethylnaphthalene from a feed stream that contains hydrocarbons which contain dimethylnaphthalene isomers. The method includes the following steps:I. distillation and concentration of the dimethylnaphthalene isomers from the feed stream, to form a dimethylnaphthalene fraction,II. isomerization of the dimethylnaphthalene fraction to enrich the dimethylnaphthalene fraction in 2,6-dimethylnaphthalene, to form a 2,6-enriched dimethylnaphthalene fraction,III. purification of 2,6-dimethylnaphthalene from the 2,6-enriched dimethylnaphthalene fraction,wherein step II is conducted in the presence of a catalyst composition containing a synthetic zeolite characterized by an X-ray diffraction pattern including interplanar d-spacing (.ANG.)12.36.+-.10.411.03.+-.0.28.83.+-.10.146.18.+-.0.126.00.+-.0.104.06.+-.0.073.91.+-.0.013.42.+-.0.06,wherein the purification includes crystallization under pressure.

Abstract: The invention discloses a method of making 2,6-dimethylnaphthalene from any DMN with one methyl on each ring in a two-step hydroisomerization/dehydrogenation process. The catalyst used in the hydroisomerization step is an acidic catalyst such as a silica aluminum catalyst with a hydrogenation/dehydrogenation metal. The catalyst used in the dehydrogenation step is a reforming type catalyst.

Abstract: A process for isomerizating a feed containing alkylaromatic hydrocarbons, e.g., monocyclic alkylaromatic hydrocarbons and/or bicyclic alkylaromatic hydrocarbons. The process is carried out by contacting the feed under conversion conditions with a zeolite bound zeolite catalyst which comprises first crystals of an intermediate pore size first zeolite and a binder which comprises second crystals of a second zeolite. The process finds particular applications in isomerizing a feed containing ethylbenzene and less than equilibrium amounts of xylenes with ethylbenzene and can produce a product containing above equilibrium quantities of para-xylene and low aromatics ring loss and xylene loss.

Abstract: A process for isomerizing a nonequilibrium xylene feed mixture is disclosed. The isomerization is conducted in the presence of hydrogen and at pressures in excess of 75 psig over a ZSM-5 type catalyst containing about 0.1 to 5 wt % of at least one metal selected from the group consisting of zinc, copper, silver and gallium. In another embodiment, the catalyst may further contain an oxide of at least one element selected from silicon, germanium and tin. The process produces a product containing about or above equilibrium quantities of para-xylene with low xylene loss.

Abstract: A reforming process, selective for the dehydrocyclization of paraffins to aromatics, is effected using a catalyst containing multiple Group VIII (8-10) noble metals having different gradients within the catalyst and a nonacidic large-pore molecular sieve. The use of this bed of catalyst results in greater selectivity of conversion of paraffins to aromatics and improved catalyst stability, particularly in the presence of small amounts of sulfur.

Abstract: A process for producing 2-methylnaphthalene from a feedstock containing 1-methylnaphthalene by contacting the feedstock with a catalyst composition, in which the process comprising isomerization of 1-methylnaphthalene,wherein the catalyst composition comprising a synthetic zeolite characterized by an X-ray diffraction pattern including interplanar d-spacing as set forth in Table A of the specification.

Abstract: A class of highly stable supergallery pillared clay compositions that have a basal spacing up to 55 .ANG. corresponding a gallery height of 35 .ANG. for samples dried at room temperature and a basal spacing up to 45 .ANG. corresponding a gallery height of 255 .ANG. for samples steamed at 800.degree. C. for 17 hours. Said compositions are prepared by special procedures including pillaring reaction in presence of poly (vinyl alcohol) as a pillaring precursor, an aging process at pH of around 4 to 9, and a calcinating or steaming treatment at high temperature. The new compositions exhibit catalytic properties and adsorption properties superior to prior art pillared clays. Said compositions are useful as catalysts for carbonium-ion reaction, and as adsorbents and catalyst carriers. They are especially suitable for preparing microspheric cracking catalysts for heavy oil or residual feedstock.

Abstract: The present invention relates to a zeolite beta catalyst characterized by critical limits of weak and strong acid species and exceptionally high catalytic activity. The catalyst is activated at a temperature effective to substantially reduce the concentration of strong acid species, i.e., hydronium cations, without substantially reducing the concentration of weak acid species, i.e., hydroxoaluminum cations, preferably following a calcining step wherein a synthesized zeolite beta catalyst containing a templating agent is calcined at a temperature in the range of from about 200.degree. to 1000.degree. C. in order to remove a substantial portion of the catalyst templating agent and an ion-exchanging step wherein the calcined catalyst is ion-exchanged with a salt solution containing at least one hydrogen forming cation selected from NH.sub.4.sup.+ and quaternary ammonium.

Abstract: Forms of zeolite Omega synthesized by hydrothermal crystallization from reaction systems containing alkali metal cations and organic templating agents, modified by calcination in air, ion-exchange, steam calcination and treatment with a low-pH aqueous ammonium ion solution, are significantly improved with respect to surface area, catalytic activity and adsorption capacities for large molecular species. A catalyst comprising zeolite Omega is effective for isomerization of aromatics and aliphatics.

Abstract: The invention relates to an alumino-silicate type catalyst containing an omega zeolite with a Si/Al atomic ratio of between 2.5 and 100, with a content by weight of sodium of less than 2000 ppm (in relation to the weight of dry zeolite) and further containing, at least one metal selected from group IIa, IIb, and IVa metals, and at least one group VIII metal.The catalyst is prepared by the grafting of an organometallic compound of said group IIa, IVb, IIb, IVa metals.The catalyst is particularly suitable for the isomerization of an aromatic C.sub.8 cut.

Abstract: An improvement to a known process in which C.sub.8 aromatic hydrocarbons are treated to recover a desired isomer of xylene, and in particular o-xylene or p-xylene. A step in recovering isomers of xylene typically includes subjecting a mixture of xylenes to fractional distillation and drawing a stream rich in o-xylene from the fractionation column. The current improvement involves the steps of contacting the contents of the fractionation column with an isomerization catalyst, thereby isomerizing C.sub.8 aromatic hydrocarbons in the fractionation column toward equilibrium and consequently enhancing the effectiveness of the fractional distillation in the recovery of the desired xylene isomer. The process can be carried out in the xylene splitter of existing apparatus by making appropriate modifications thereto. It also can be carried out in newly-designed and fabricated apparatus. Embodiments are disclosed for favoring the production either of o-xylene or p-xylene.

Abstract: This invention presents a novel MgAPSO molecular sieve, containing a critical range of magnesium in the sieve framework and having a small crystallite size, which is particularly active for hydrocarbon conversion. The sieve advantageously is incorporated, along with a platinum-group metal, into a catalyst formulation which is useful for isomerization. When utilized in a process for isomerizing a non-equilibrium mixture of xylenes containing ethylbenzene, a greater yield of para-xylene is obtained compared to prior-art processes.

Abstract: There is disclosed a method for isomerizing dimethylnaphthalene (DMN) in liquid phase under atmospheric pressure by using a catalyst comprising hydrogen-form mordenite which has a molar ratio of silica to alumina (SiO.sub.2 /Al.sub.2 O.sub.3 ratio) of at least 100 and is molded by incorporating alumina as the molding aid therein. According to the above method, the objective 2,6-DMN minimized in the contents of impurities can stably be produced in high selectivity and high yield under mild reaction conditions for a long period of time, while side reactions and deterioration of the catalyst are suppressed to a minimum.

Abstract: Hydrocarbon conversion processes are described which use novel microporous compositions. These compositions have a three-dimensional microporous framework structure of ZnO.sub.2, PO.sub.2 and M'O.sub.2 tetrahedral units, and an intracrystalline pore system. The M' metal is selected from the group consisting of magnesium, copper, gallium, aluminum, germanium, cobalt, chromium, iron, manganese, titanium and mixtures thereof. Examples of the hydrocarbon conversion processes include hydrocracking, hydrotreating and hydrogenation.

Abstract: A method for preparing one or more specific dimethyltetralins from either 5-(o-, m-, or p-tolyl)-pent-1- or -2-ene or 5-phenyl-hex-1- or -2-ene, and optionally for preparing one or more specific dimethylnaphthalenes from the aforesaid dimethyltetralins is disclosed wherein the orthotolylpentene or phenylhexane is cyclized to the dimethyltetralin using an ultra-stable crystalline aluminosilicate molecular sieve Y-zeolite.

Abstract: This invention relates to hydrocarbon conversion processes using novel molecular sieve compositions as the catalyst. These molecular sieves contain chromium in the framework structure along with aluminum and silicon. The process of preparing the chromium-containing molecular sieves involves contacting a starting molecular sieve with a solution or slurry of a fluoro salt of chromium under effective process conditions to provide for aluminum extraction and substitution of chromium.

Abstract: A catalytic process for the conversion of hydrocarbons is described. Catalyst in this improved process is made by thermally activating a hydrotalcite-type clay of formula:M.sup.2+.sub.2x M.sup.3+.sub.2 (OH).sub.4x+4 A.sup.n-.sub.2/n.ZH.sub.2 Owhere M.sup.2+ is one or more metal ion selected from the group consisting of Mg.sup.2+, Zn.sup.2+ Cu.sup.2+, Ni.sup.2+, Co.sup.2+, Mn.sup.2+ and Fe.sup.2+ and M.sup.3+ is one or more metal ion selected from the group consisting of Al.sup.3+, Fe.sup.3+, Co.sup.3+, Mn.sup.3+ and Cr.sup.3+, x runs between 1.5 and 5, A is one or more anions selected from the group consisting of B(OH).sub.4.sup.-, [B.sub.3 O.sub.3 (OH).sub.4 ].sup.-, V.sub.2 O.sub.7.sup.4-, V.sub.4 O.sub.12.sup.4-, and V.sub.3 O.sub.9.sup.3-, n is 1, 3 or 4, and Z runs between 0 and about 4. These hydrotalcite-type clays have an X-ray diffraction d(001) value greater than about 7.7 Angstroms.

Abstract: This invention presents a novel MgAPSO molecular sieve, containing a critical range of magnesium in the sieve framework, which is particularly active for hydrocarbon conversion. The sieve advantageously is incorporated, along with a platinum-group metal, into a catalyst formulation which is useful for isomerization. When utilized in a process for isomerizing a non-equilibrium mixture of xylenes containing ethylbenzene, a greater yield of para-xylene is obtained compared to prior-art processes.

Abstract: There is provided a crystalline oxide material with a characteristic X-ray diffraction pattern. This material may be a layered material, which is swollen or pillared. Upon calcination of the swollen material, the layers collapse and condense upon one another in a somewhat disordered fashion to form a non-swellable material. However, the swollen layered material may be intercalated with polymeric oxide pillars to maintain layer separation, even after calcination.

Abstract: There is provided a molecular sieve coated with a non-oxide ceramic. The molecular sieve may be a zeolite, such as ZSM-5, and the ceramic coating may be, e.g., boron nitride. The coated molecular sieve may be prepared by contacting the molecular sieve with a ceramic precursor material comprising a thermally decomposable material, such as polyborazylene, and thermally decomposing this thermally decomposable material. The coated molecular sieves may be used as organic conversion catalysts. The non-oxide ceramic coating may alter or enhance the shape-selective properties of the molecular sieve by providing a diffusion barrier to molecules.

Abstract: The invention relates to a catalyst for isomerizing a C.sub.8 aromatic fraction containing a mordenite and at least one metal from group VIII of the periodic classification of elements (such as Pt or Pd), characterized in that the mordenite is such that its skeleton Si/Al atomic ratio is between 6 and 10.5, its sodium weight content is below 2000 ppm, its unit cell volume is between 2.73 and 2.78 nm.sup.3, its benzene adsorption capacity is between 4 and 10% based on the dry mordenite weight and its 1,3,5-trimethylbenzene adsorption capacity is between 0.5 and 2.5% by weight based on the dry mordenite weight. The invention also relates to the preparation of said mordenite.

Abstract: This invention deals with a hydrocarbon conversion process using a crystalline oxysulfide composition. The crystalline oxysulfide composition has a three-dimensional microporous framework structure of at least MO.sub.2, MS.sub.2, and MOS tetrahedral units, having an intracrystalline pore system and an empirical formula expressed in molar ratios:(M.sub.s Al.sub.t P.sub.u Si.sub.v)S.sub.w O.sub.2-wwhere M is at least one metal selected from the group consisting of metals which: 1) can be incorporated into the framework structure of a microporous molecular sieve and 2) form hydrolytically stable sulfides; s, t, u, v and w are the mole fractions of M, Al, P, Si and S respectively. The values of s, t, u and v are chosen such that when t is greater than zero u is greater than zero, s+t+u+v=1 and when s=1, M is only a combination of gallium and germanium.

Abstract: This invention deals with a crystalline oxysulfide composition, a process for preparing the composition, a catalyst using the composition and processes using the composition. The crystalline oxysulfide composition has a three-dimensional microporous framework structure of at least MO.sub.2, MS.sub.2, and MOS tetrahedral units, having an intracrystalline pore system and an empirical formula expressed in molar ratios:(M.sub.s Al.sub.t P.sub.u Si.sub.v)S.sub.w O.sub.2-wwhere M is at least one metal selected from the group consisting of metals which: 1) can be incorporated into the framework structure of a microporous molecular sieve and 2) form hydrolytically stable sulfides; s, t, u, v and w are the mole fractions of M, Al, P, Si and S respectively. The oxysulfide composition is prepared by contacting a molecular sieve having an empirical formula: (M.sub.s Al.sub.t P.sub.u Si.sub.v)O.sub.

Abstract: The catalytic conversion of hydrocarbon feedstocks is affected under effective conversion process conditions in the presence of silicoaluminophosphate-based catalyst compositions.

Abstract: A method for preparing one or more specific dimethyltetralins from either 5-(o-, m-, or p-tolyl)-pent-1-or -2-ene or 5-phenyl-hex-1- or -2-ene, and optionally for preparing one or more specific dimethylnaphthalenes from the aforesaid dimethyltetralins is disclosed.

Abstract: A process is provided for converting feedstock alkylaromatic compounds by isomerization over a catalyst comprising MCM-22.

Abstract: A catalyzed process for the isomerization of a xylene-containing stream containing a major amount of ethylbenzene under supercritical temperature and pressure which contacts the stream under supercritical conditions with a catalyst and subsequently reduces the temperature of the isomerization product at a pressure above the critical pressure.

Abstract: This invention presents a novel catalyst formulation for the isomerization of alkylaromatic hydrocarbons. The catalyst is comprised of at least one Group VIII metal, and a pentasil zeolite having an x-ray diffraction characteristic of ZSM-12 wherein a portion of the aluminum atoms have been replaced with gallium atoms. When utilized in a process for isomerizing a non-equilibrium mixture of xylenes containing ethylbenzene, a greater yield of paraxylene is obtained compared to prior-art processes.

Abstract: Gallium-containing, crystalline silicate molecular sieves in which substantially all of the gallium occupies molecular sieve lattice positions or is intimately associated with the crystal lattice of the silicate sieve when composited into a silica matrix are shown to form catalyst compositions having superior properties for the catalytic, liquid-phase isomerization of a xylene-containing stream containing a minor amount of ethylbenzene to a product mixture rich in paraxylene.

Abstract: A method for preparing one or more specific dimethyltetralins from either 5-(o-, m-, or p-tolyl)-pent-1- or -2-ene or 5-phenyl-hex-1- or -2-ene, and optionally for preparing one or more specific dimethylnaphthalenes from the aforesaid dimethyltetralins is disclosed.

Abstract: A crystalline, galliosilicate molecular sieve having the erionite-type structure and the following composition expressed in terms of oxide mole ratios in the anhydrous state:Ga.sub.2 O.sub.3 :xSiO.sub.2 :yM.sub.2 O:zN.sub.2 O:tQ.sub.2 Owhere M is an alkali metal, preferably sodium, N is an alkali metal other than M, preferably potassium, Q is a cation derived from the templating agent used in synthesizing the galliosilicate molecular sieve, preferably a choline cation, x equals 5.5 to 30, y equals 0.1 to 0.9, z equals 0.1 to 0.9, t equals 0.1 to 0.6 and y+z+t equals about 1.0. The crystalline, galliosilicate molecular sieve of the invention may be employed, after reducing its alkali metal content, as a component of a catalyst which can be used in a variety of chemical conversion processes, preferably hydrocarbon conversion processes, and most preferably hydrodewaxing, hydrocracking and isomerization processes.

Abstract: Hydrocarbon conversion processes are disclosed using a catalyst prepared by a method comprising reacting an adsorbent containing surface hydroxyl groups with a Lewis acid in a halogenated organic solvent.

Abstract: An improved process employing a supported, platinum-containing, crystalline, silicate molecular sieve catalyst composition effective in removing ethylbenzene from unextracted xylene feeds during isomerization, primarily by hydrodeethylation, and also the primarily C.sub.9 paraffins and naphthenes. Choosing (1) a set of process conditions within narrow ranges of temperature T, total pressure P, and hydrogen to hydrocarbon mol ratio H/HC such that Z, which is defined as a function of T, P and H/HC, is less than about 0.01, and (2) a platinum-containing catalyst composition, greatly reduces the feed C.sub.9 paraffins and naphthenes content during isomerization, removes most of the ethylbenzene by hydrodeethylation to ethane and benzene, and minimizes xylene loss to hydrogenation and cracking, all without substantially changing the excellent isomerization properties of the sieve catalyst composition.

Abstract: Described are catalyst mixtures comprising a HAMS-1B crystalline borosilicate molecular sieve incorporated into an inorganic matrix component and a molybdenum on silica component. These mixtures when used to isomerize unextracted xylene streams containing ethylbenzene to mixtures rich in paraxylene demonstrate improved paraffins and naphthenes conversion to light hydrocarbons and convert most of the ethylbenzene by a hydrodeethylation mechanism to benzene and ethane.

Abstract: Crystalline molecular sieves having three-dimensional microporous framework structures of TiO.sub.2, AlO.sub.2, SiO.sub.2 and PO.sub.2 tetrahedral units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR: (Ti.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (Ti.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2 ; and "w", "x", "y" and "z" represent the mole fractions of titanium, aluminum, phosphorus and silicon, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.

Abstract: A novel family of crystalline, microporous gallophosphate compositions is synthesized by hydrothermal crystallization at elevated temperatures from gallophosphate gels containing a molecular structure-forming template. The family comprises distinct species, each with a unique crystal structure. Calcination removed volatile extraneous matter from the intracrystalline void space and yields microporous crystalline adsorbents with pores, the dimensions of which vary, among the individual species, from about 3A to 10A in diameter. The compositions represent a new class of adsorbents of the molecular sieve type, and also exhibit properties somewhat analogous to zeolitic molecular sieves which render them useful as catalysts or catalyst based in chemical reactions such as hydrocarbon conversion.

Abstract: Molecular sieve compositions having three-dimensional microporous framework structures of CrO.sub.2, AlO.sub.2 and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR: (Cr.sub.x Al.sub.Y P.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (Cr.sub.x Al.sub.y P.sub.z)O.sub.2 ; and "x", "y" and "z" represents the mole fractions of chromium, aluminum and phosphorus, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.

Abstract: Crystalline molecular sieves having three-dimensional microporous framework structures of MnO.sub.2, AlO.sub.2, SiO.sub.2 and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis expressed by the formula:mR: (Mn.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (Mn.sub.w Al.sub.x P.sub.y Si.sub.z)O.sub.2 ; and "w", "x", "y" and "z" represent the mole fractions of manganese, aluminum, phosphorus and silicon, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is also disclosed.

Abstract: Delaminated clays whose X-ray diffraction patterns do not contain a distinct first order reflection are prepared from synthetic and natural swelling clays whose particles have a length-to-width ratio greater than about 2.0, a length-to-thickness ratio greater than about 5.0 and are comprised of randomly oriented platelets by reacting the clay with a pillaring agent selected from the group consisting of polyoxymetal cations, mixtures of polyoxymetal cations, colloidal particles comprising alumina, silica, titania, chromia, tin oxide, antimony oxide or mixtures thereof, and cationic metal clusters comprising nickel, molybdenum, cobalt or tungsten and then subjecting the resulting reaction products to drying in a gaseous medium, preferably spray drying. The resulting acidic delaminated clays, which contain the microporosity associated with zeolites and pollared clays and the macroporosity associated with amorphous aluminosilicates, may be used as the active component of cracking and hydroprocessing catalysts.

Abstract: Crystalline molecular sieves having three-dimensional microporous framework structure of MO.sub.2, AlO.sub.2, and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis are expressed by the formula:mR: (M.sub.x Al.sub.y P.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (M.sub.x Al.sub.y P.sub.z)O.sub.2 ; "M" represents at least two elements capable of forming framework tetrahedral oxides and selected from the group consisting of arsenic, beryllium, boron, chromium, gallium, germanium, lithium and vanadium; and "x", "y" and "z" represent the mole fractions of "M", aluminum and phosphorus, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is disclosed. The catalyst is useful in the cracking and hydrocracking of various hydrocarbonaceous feeds.

Abstract: A process for producing a thermally shock calcined aluminosilicate zeolite comprising (A) precalcining an aluminosilicate zeolite at a relatively low temperature, (B) very rapidly increasing the temperature of the aluminosilicate zeolite to a relatively high temperature for a short period of time, and (C) rapidly cooling the aluminosilicate zeolite. The resulting zeolite is catalytically active for hydrocarbon conversion reactions and is particularly selective for the production of para-xylene from a reaction mix of toluene and a methylating agent.

Abstract: A process for producing a thermally shock calcined crystalline silica comprising (A) precalcining a crystalline silica at a relatively low temperature, (B) very rapidly increasing the temperature of the crystalline silica to a relatively high temperature for a short period of time, and (C) rapidly cooling the crystalline silica. The resulting crystalline silica is catalytically active for hydrocarbon conversion reactions and is particularly selective for the production of para-xylene from a reaction mix of toluene and a methylating agent.

Abstract: Novel class of crystalline microporous ferroaluminophosphate compositions containing as lattice constituents in addition to AlO.sub.2 and PO.sub.2 structural units, ferric and/or ferrous iron in tetrahedral coordination with oxygen atoms. These compositions are prepared hydrothermally using organic templating agents and are suitably employed as catalysts or adsorbents.

Abstract: There is provided a catalytic composition which comprises a mixture of a crystalline chromosilicate and an oxide of chromium, said catalytic composition providing a specific X-ray diffraction pattern and having the following composition in terms of mole ratios of oxides:0.9.+-.0.2 M.sub.2/n O:Cr.sub.2 O.sub.3 :YSiO.sub.2 :ZH.sub.2 O,wherein M is at least one cation having a valence of n, Y is a value within the range of about 4 to about 500, and Z is a value within the range of about 0 to about 160. There is also provided a method for preparing such a catalytic composition.There is provided a process for the conversion of a hydrocarbon stream which comprises contacting said stream at conversion conditions with the above catalytic composition. In addition, there is provided a process for the isomerization of a xylene feed which comprises contacting said feed at isomerization conditions with the above catalytic composition.

Abstract: Xylene isomerization is carried out using specific non-zeolitic molecular sieve catalyst, e.g., the silicoaluminophosphate molecular sieves of U.S. Pat. No. 4,440,871, to provide improved production of p-xylene from C.sub.8 aromatic compounds and the conversion of ethylbenzene to a xylene.

Abstract: A novel catalytic absorbent composition is prepared with a synthetic copper or silver carbonate-containing material. The absorbent is useful for removing hydrogen sulfide and mercaptan sulfur from hydrocarbon oils, especially from feedstreams to a reformer.