Abstract: The object of the present invention relates to a simple, rapid and inexpensive process for effecting solid-liquid separations in the case of zeolites, also having small crystals. This process, which is particularly useful for the recovery of zeolite crystals in suspension in the crystallization water, comprises treating this suspension of crystals with an acid or one of its precursors and subjecting the resulting mixture to filtration or decanting. According to a particular aspect of the invention, the crystalline phase is separated in a mixture with oxides which can be used as ligands. Said oxides can be generated by the reagents of the zeolite preparation reagent mixture, not transformed into crystalline phase during the synthesis hydrothermal treatment, or they can be added to the suspension of crystals before the separation treatment, or again they can be generated by precursors suitably added to the crystallization slurry.

Abstract: Catalyst based on molibden and silicon having a surface area ranging from 20 to 400 m2/g and a molar ratio Mo/Si>0.2 obtainable with a process which comprises: a) dissolving a soluble molibden salt in an aqueous solution containing at least one basic compound selected from ammonium hydroxides having general formula (I): R1R2R3R4N+OH−  (I) b) adding to the solution of step (a) at least one compound of silicon capable of hydrolyzing to Sio2; c) gelifying and calcining the gel obtained.

Abstract: Catalyst based on molibden and silicon having a surface area ranging from 20 to 400 m2/g and a molar ratio Mo/Si>0.

Abstract: A process is described for the preparation of zeolitic catalysts in the form of microspheres, comprising zeolite and oligomeric silica, characterized by a high mechanical resistance. The process consists in subjecting to rapid drying the suspension, to which tetra-alkylorthosilicate is optionally added, resulting from the synthesis of zeolite by hydrothermal treatment at autogenous pressure of the reagent mixture containing tetra-alkylammoniumhydroxide as templating agent, and subjecting the product resulting from the drying to calcination.

Abstract: The present invention relates to a process for the preparation of zeolitic catalysts comprising zeolite and oligomeric silica, which can be used in industrial reactors. The process consists in directly mixing the suspension, resulting from the synthesis of the zeolite, with an oligomeric silica sol, obtained from the hydrolysis of a tetra-alkyl ortho silicate in the presence of tetra-alkylammonium hydroxide, and in subjecting the mixture to rapid drying, by feeding to a spray-dry.

Abstract: A synthetic, crystalline, porous material is disclosed, together with the related preparation process. Such material of zeolitic nature containing oxides of silicon, titanium and gallium corresponds, in the calcined and anhydrous state, to the following empyrical formula:pHGaO.sub.2 .multidot.qTiO.sub.2 .multidot.SiO.sub.2,wherein p has a value greater than zero and smaller than or equal to 0.050, and q has a value greater than zero and smaller than or equal to 0.025, and the H.sup.+ of HGaO.sub.2 can be at least partially replaceable or replaced by cations.

Abstract: The present invention relates to a process for the preparation of a micro-meso porous material which comprises:a) preparing a mixture starting from a tetraalkylorthosilicate, a C.sub.3 -C.sub.6 alkyl alcohol or dialcohol, a tetraalkylammonium hydroxide having the formula R.sub.1 (R.sub.2).sub.3 N--OH wherein R.sub.1 is a C.sub.3 -C.sub.7 alkyl and R.sub.2 is a C.sub.1 or C.sub.3 -C.sub.7 alkyl, optionally in the presence of one or more metal compounds, in which the molar ratios are within the following ranges:alcohol/SiO.sub.2 <or equal to 20;R.sub.1 (R.sub.2).sub.3 N--OH/SiO.sub.2 =0.05-0.4;H.sub.2 O/SiO.sub.2 =1-40;metal oxides/SiO.sub.2 =0-0.02;b) subjecting this mixture to hydrolysis and subsequent gelation at a temperature of between 20.degree. C. and a temperature close to the boiling point of the alcohol or mixture of alcohols present;c) subjecting the gel obtained to drying and calcination.

Abstract: A superacid catalyst comprising zirconium oxide having a purely tetragonal crystalline phase structure and whose surface has sulfate groups thereon in a quantity corresponding to the total coverage of the surface of the zirconium oxide by a monolayer of said sulfate groups, the zirconium oxide having a porosimetric distribution consisting of at least 70% of pores having a diameter ranging from 1-4 nm.

Abstract: Process for the hydroisomerization of n-paraffins in the presence of a difunctional catalyst which comprises:(a) a porous crystalline material isostructural with beta-zeolite selected from boro-silicate (BOR-B) and boro-alumino-silicate (AL-BOR-B) in which the molar SiO.sub.2 :Al.sub.2 O.sub.3 ratio is higher than 300:1;(b) one or more metal(s) belonging to Group VIIIA, selected from platinum and palladium, in an amount comprised within the range of from 0.05 to 5% by weight.

Abstract: Process for the preparation of amides via the catalytic rearrangement of oximes which comprises putting an oxime in vapor phase in contact with a catalyst selected from a mesoporous silica-alumina having a molar ratio SiO/Al.sub.2 O.sub.2 of between 20 and 1000, an average pore diameter of between 20 and 100 .ANG. and an X-ray diffraction pattern (XRD) from powders which, after calcination, has the deepest reflection at d-spacing of more than 18 .ANG. (2.theta.<4.9.degree., CuK.alpha. radiation).

Abstract: Process for the preparation of caprolactam by the catalytic rearrangement of cyclohexanone oxime in which a vapour phase oxime is contacting a catalyst selected from an essentially amorphous, micro-mesoporous silica-alumina having a molar ratio SiO.sub.2 /Al.sub.2 O.sub.3 of 30 to 5000, a surface area of at least 500 m.sup.2 /g and a total pore volume of 0.3 to 1.3 ml/g.

Abstract: Process for the hydroisomerization of n-paraffins in the presence of a difunctional catalyst which comprises:(a) a porous crystalline material isostructural with beta-zeolite selected from boro-silicate (BOR-B) and boro-alumino-silicate (Al-BOR-B) in which the molar SiO.sub.2 :Al.sub.2 O.sub.3 ratio is higher than 300:1;(b) one or more metal(s) belonging to Group VIIIA, selected from platinum and palladium, in an amount comprised within the range of from 0.05 to 5% by weight.

Abstract: A synthetic, crystalline, porous material is disclosed, together with the related preparation process. Such material of zeolitic nature containing oxides of silicon, titanium and gallium corresponds, in the calcined and anhydrous state, to the following empyrical formula:pHGaO.sub.2.qTiO.sub.2.SiO.sub.2,wherein p has a value greater than zero and smaller than or equal to 0.050, and q has a value greater than zero and smaller than or equal to 0.025, and the H.sup.+ of HGaO.sub.2 can be at least partially replaceable or replaced by cations.

Abstract: A catalytically active gel is described consisting of a silica matrix with uniform porosity, monomodal pore distribution and high surface area, within which one or metal oxides possessing catalytic activity are dispersed. A process for preparing this catalytic gel is also described.

Abstract: A catalytically active gel product is described consisting of a silica matrix which is amorphous to x-rays with uniform porosity, monomodal pore distribution and high surface area, within which one or more metal oxides possessing catalytic activity are dispersed. A process for preparing this catalytic gel is also described.

Abstract: A novel method for preparing crystalline, porous boro-silicates and boron-metal-silicates isostructural with beta zeolite is disclosed.This method makes it possible the times required by the synthesis of such zeolites to be reduced, and said preparations to be carried out with larger reaction volumes.

Abstract: A silica and alumina gel is disclosed, which is amorphous at X-rays, has a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 comprised within the range of from 30/1 to 500/1, a surface area comprised within the range of from 500 to 1000 m.sup.2 /g, a total volume of pores comprised within the range of from 0.3 to 0.6 ml/g, an average diameter of the pores of the order of magnitude of 10 .ANG. or less and which is free, or substantially free, from pores having a diameter larger than 30 .ANG..Such a silica and alumina gel is catalytically active in reactions of conversion of the hydrocarbons, such as: oligomerization, alkylation, isomerization and dewaxing.Also a process for preparing such a silica and alumina gel is disclosed.