Abstract: Process for the production of propylene starting from mixtures of hydrocarbons, prevalently olefins, the above hydrocarbons having a boiling point ranging from ?15° C. to +80° C., preferably from ?12° C. to +60° C., which comprises putting the above mixture of hydrocarbons in contact, under cracking conditions, with a large-pore zeolite having a molar ratio Silica/Alumina lower than 200, preferably ranging from 50 to 150.

Abstract: The present invention relates to a mesoporous gel comprising an alumina matrix in which one or more oxides selected from silica, boron oxide, phosphorus oxide, oxides of metals of groups VIII and VIB, may be uniformly dispersed. The present invention also relates to a process for the preparation of this gel and its uses as carrier, as catalyst for acid-catalyzed reactions and as hydrotreating catalyst.

Abstract: Process for the preparation of a middle distillate having good properties at low temperatures, which can be used as fuel, starting from a mixture of substantially linear hidrocarbons, without sulfur and containing at least 20% of a high-boiling fraction having a distillation temperature exceeding 370° C., comprising, as single reactive step, a “hydrocracking” step on said mixture of linear hydrocarbons, at a temperature ranging from 250 to 450° C. and a total pressure of 0.5 to 15 MPa, in the presence of a supported catalyst comprising: (A) a carrier of an acid nature consisting of a calcined gel of silica-alumina amorphous to X-rays having a molar ratio between silica and alumina within the range of 30 and 500, a surface area within the range of 500 and 1000 m2/g, with a porosity within the range of 0.2 and 0.

Abstract: A superacid catalyst comprising: zirconium oxide on whose surface sulfate groups are present, in a quality corresponding to total coverage of the surface of the zirconium oxide by means of a monolayer of these sulfate groups, optionally containing a noble metal in a quantity ranging from 0.1 to 3% by weight, with a porosity ranging from 0.1 to 0.30 cm3/g, consisting of at least 70% of pores with a diameter ranging from 1 to 4 nm, prepared by a process which comprises: (a) hydrolyzing derivate of zirconium in a basic medium in the presence of a tetra-alkylammonium hydroxide (TAA), sulfuric acid and acetylacetone (AcAc); (b) drying the product of step (a) and calcining the dried material at a temperature ranging from 250 to 650° C. (c) optionally treating the product resulting from step (b) with an aqueous solution of a compound of a noble metal, and drying and calcining the treated product.

Abstract: Process for the production of propylene starting from mixtures of hydrocarbons, prevalently olefins, the above hydrocarbons having a boiling point ranging from −15° C. to +80° C., preferably from −12° C. to +60° C., which comprises putting the above mixture of hydrocarbons in contact, under cracking conditions, with a large-pore zeolite having a molar ratio Silica/Alumina lower than 200, preferably ranging from 50 to 150.

Abstract: The preparation is disclosed of an extruded catalyst based on a silica/alumina gel, which catalyst is particularly active in acid-catalyzed reactions, such as the oligomerization of light olefins, e.g., propylene.

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 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: An amorphous, micro/mesoporous silica-alumina gel with controlled pore size, having a surface area of at least 500 m.sup.2 /g and with a molar ratio of SiO.sub.2 :Al.sub.2 O.sub.3 of at least 30:1, is prepared by hydrolysing and causing a tetra-alkyl ammonium hydroxide, an aluminum trialkoxide, and a tetra-alkyl orthosilicate to gelate, by operating at a temperature equal to, or higher than, the boiling temperature, under atmospheric pressure, of any alcohols which are developed as a by-product from said hydrolysis reaction, without said alcohols being removed, or being substantially removed, from the reaction media; and the so produced gel being dried and fired.

Abstract: An amorphous, micro/mesoporous silica-alumina gel with controlled pore size, having a surface area of at least 500 m.sup.2 /g and with a molar ratio of SiO.sub.2 :Al.sub.2 O.sub.3 of at least 30:1, is prepared by hydrolysing and causing a tetra-alkyl ammonium hydroxide, an aluminum trialkoxide, and a tetra-alkyl orthosilicate to gelate, by operating at a temperature equal to, or higher than, the boiling temperature, under atmospheric pressure, of any alcohols which are developed as a by-product from said hydrolysis reaction, without said alcohols being removed, or being substantially removed, from the reaction media; and the so produced gel being dried and fired. So obtained gel is an active catalyst in hydrocarbon conversion reactions, in particular in light olefin isomerization and oligomerization processes, e.g., in propylene oligomerization processes to yield useful liquid hydrocarbons for gasoline and jet fuel formulation.

Abstract: A catalyst, which is active in the oligomerization of olefins is an X-ray-amorphous silica-alumina-nickel oxide gel having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of from 30/1 to 500/1, and NiO/SiO.sub.2 molar ratio of from 0.001/1 to 0.01/1, a superficial area of from 500 m.sup.2 /g to 1.000 m.sup.2 /g, and a porosity of from 0.3 ml/g to 0.6 ml/g, the means pore diameter being 1 nm (10 Angstrom), and devoid of pores having a diameter over 3 nm (30 Angstrom). The catalyst selectively dimerizes isobutene into alpha- and beta-isobutene and oligomerizes propylene into its relative dimers and trimers. A process is described for preparing the silica-alumina-nickel oxide gel.

Abstract: The preparation is disclosed of an extruded catalyst based on a silica/alumina gel, which catalyst is particularly active in acid-catalyzed reactions, such as the oligomerization of light olefins, e.g., propylene.

Abstract: Disclosed is a process for carrying out the selective dimerization of isobutene in order to produce alpha- and beta-di-isobutene dimer.sub.3, according to which process an isobutene stream is brought into contact, under dimerization conditions, with a solid silica gel/alumina catalyst which is amorphous when analyzed by X-ray diffraction, displays a molar ratio of SiO.sub.2 /Al.sub.2 O.sub.3 comprised within the range of from 30:1 to 500:1, has a surface-area comprised within the range of from 500 to 1000 m.sup.2 /g, a porosity of from 0.3 to 0.6 ml/g and an average pore diameter of approximately 10 .ANG. (.ANG.ngstrom), and is free from pores with a larger diameter than 30 .ANG..