Abstract: Mixed oxide vanadium/antimony/titanium ammoxidation catalysts, particularly suited for the ammoxidation of alkanes and exhibiting X-ray diffraction spectra which are characteristic of a crystallographic phase of rutile TiO.sub.2, are prepared by (a) dissolving respective soluble compounds of vanadium, of antimony and of titanium in at least one saturated alcohol, (b) contacting the alcoholic solution thus obtained with water and precipitating the mixed oxide therefrom, and (c) separating and calcining the mixed oxide thus precipitated.

Abstract: This invention provides a process for the selective production of cumene comprising reacting benzene with propylene in the presence of a type-Y zeolite modified by treatment with a phosphorous compound. This invention also provides a process for the transalkylation of a polyalkylated benzene which comprises reacting the polyalkylated benzene in the presence of benzene and a type-Y zeolite modified by treatment with a phosphorous compound.

Abstract: A process for oligomerizing propylene is described, consisting of reacting said olefin in the presence of an X-ray amorphous alumina-silica gel catalyst with a silica/alumina molar ratio of between 30/1 and 500/1, a surface area of between 500 and 1000 m.sup.2 /g, a total pore volume of between 0.3 and 0.6 ml/g, an average pore diameter of the order of 10 .ANG. or less, and free or substantially free of pores with a diameter greater than 30 .ANG..

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.

Abstract: Cumene is prepared by alkylation of benzene with propylene, or by transalkylation of diisopropylbenzenes in the presence of benzene, on a silica and alumina gel catalyst which is amorphous to X-rays and has an SiO.sub.2 /Al.sub.2 O.sub.3 ratio of between 50/1 and 300/1, a surface area of between 500 and 1000 m.sup.2 /g, an overall pore volume of between 0.3 and 0.6 ml/g and mean pore diameter of the order of 10 .ANG., and which is free or substantially free of pores having a diameter exceeding 30 .ANG..

Abstract: An oxidation catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure is obtained by a process which comprises the following stages:(a) preparation of a solution of Ti(IV) by dissolution (partial hydrolysis) of TiCl.sub.4 in an aqueous solution at a final pH below 1.0,(b) preparation of a solution of V(IV) by heating, in order to dissolve it, solid V.sub.2 O.sub.5 suspended in an aqueous oxalic acid solution,(c) precipitation of metatitanic acid from the Ti(IV) solution at a pH not higher than 1.3,(d) precipitation of vanadium oxide from the said V(IV) solution in the presence of the metatitanic acid obtained in (c), and(e) separation of the precipitate, dyring and calcination thereof at an elevated temperature.The process provides a catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure, which has a specific surface area of the order of 10 to 60 m.sup.

Abstract: An oxidation catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure is obtained by a process which comprises the following stages:(a) preparation of a solution of Ti(IV) by dissolution (partial hydrolysis) of TiCl.sub.4 in an aqueous solution at a final pH below 1.0,(b) preparation of a solution of V(IV) by heating, in order to dissolve it, solid V.sub.2 O.sub.5 suspended in an aqueous oxalic acid solution,(c) precipitation of metatitanic acid from the Ti(IV) solution at a pH not higher than 1.3,(d) precipitation of vanadium oxide from the said V(IV) solution in the presence of the metatitanic acid obtained in (c), and(e) separation of the precipitate, drying and calcination thereof at an elevated temperature.The process provides a catalyst formed from V.sub.2 O.sub.5 and TiO.sub.2 of rutile structure, which has a specific surface area of the order of 10 to 60 m.sup.