The present invention addresses to obtaining a support of hydrorefining catalysts by an innovative preparation route that reduces the problem of loss (or leaching) of boron over the operating time of industrial units. As the presence of boron in catalysts contributes to increased activity (hydrogenating and acidic) and stability for the hydrorefining reactions (hydrotreating and hydrocracking), its maintenance in the catalyst guarantees the preservation of the properties in operation, throughout the entire cycle of campaign of industrial units.

The present invention addresses to obtaining a support of hydrorefining catalysts by an innovative preparation route that reduces the problem of loss (or leaching) of boron over the operating time of industrial units. As the presence of boron in catalysts contributes to increased activity (hydrogenating and acidic) and stability for the hydrorefining reactions (hydrotreating and hydrocracking), its maintenance in the catalyst guarantees the preservation of the properties in operation, throughout the entire cycle of campaign of industrial units.

The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA) comprising at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active material of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %. The present invention further relates to a process for gas phase oxidation in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active materials of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %.

The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA) comprising at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active material of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %. The present invention further relates to a process for gas phase oxidation in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active materials of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %.

This invention is directed to a method of oxygenating hydrocarbons with molecular oxygen, O.sub.2, as oxidant under electrochemical reducing conditions, using polyoxometalate compounds containing copper such as Q.sub.10[Cu.sub.4(H.sub.2O).sub.2(B-α-PW.sub.9O.sub.34).sub.2] or Q.sub.13{[Cu(H.sub.2O)].sub.3[(A-α-PW.sub.9O.sub.34).sub.2(NO.sub.3).sup.−]} or solvates thereof as catalysts, wherein Q are each independently selected from alkali metal cations, alkaline earth metal cations, transition metal cations, NH.sub.4.sup.+, H.sup.+ or any combination thereof.

This invention is directed to a method of oxygenating hydrocarbons with molecular oxygen, O.sub.2, as oxidant under electrochemical reducing conditions, using polyoxometalate compounds containing copper such as Q.sub.10[Cu.sub.4(H.sub.2O).sub.2(B-α-PW.sub.9O.sub.34).sub.2] or Q.sub.13{[Cu(H.sub.2O)].sub.3[(A-α-PW.sub.9O.sub.34).sub.2(NO.sub.3).sup.−]} or solvates thereof as catalysts, wherein Q are each independently selected from alkali metal cations, alkaline earth metal cations, transition metal cations, NH.sub.4.sup.+, H.sup.+ or any combination thereof.

An object of the present invention is to provide an exhaust gas purification catalyst having improved exhaust gas purifying performance (in particular, improved NOx purifying performance) at low to medium temperature, and, in order to achieve the object, the present invention provides an exhaust gas purification catalyst (10A) including: a substrate (20); and a catalyst layer (30 or 40) formed on the substrate (20), wherein the catalyst layer (30 or 40) contains rhodium element, phosphorus element and a rare earth element other than cerium element, wherein a ratio of a mass of the phosphorus element contained in the catalyst layer (30 or 40) to the mass of the rhodium element contained in the catalyst layer (30 or 40) is from 1 to 10, and wherein a ratio of a mass of the rare earth element other than cerium element in terms of an oxide thereof contained in the catalyst layer (30 or 40) to the mass of the rhodium element contained in the catalyst layer (30 or 40) is from 1 to 5.

The invention relates to a catalyst comprising a support based on alumina or silica or silica-alumina, at least one group VIII element, at least one group VIB element and at least one organic compound of formula (I) ##STR00001##
in which R.sub.1 is a hydrocarbon-based radical comprising from 1 to 12 carbon atoms, R.sub.2 and R.sub.3 are chosen from a hydrogen atom and a hydrocarbon-based radical comprising from 1 to 12 carbon atoms, X is chosen from an oxygen atom or a sulfur atom except when R.sub.2 and R.sub.3 represent a hydrogen atom, in which case X is an oxygen atom, Y is chosen from a hydrogen atom, a hydrocarbon-based radical comprising from 1 to 12 carbon atoms or a unit —C(O)R.sub.4, R.sub.4 being chosen from a hydrogen atom and a hydrocarbon-based radical comprising from 1 to 12 carbon atoms.

The invention relates to a catalyst comprising a support based on alumina or silica or silica-alumina, at least one group VIII element, at least one group VIB element and at least one organic compound of formula (I) ##STR00001##
in which R.sub.1 is a hydrocarbon-based radical comprising from 1 to 12 carbon atoms, R.sub.2 and R.sub.3 are chosen from a hydrogen atom and a hydrocarbon-based radical comprising from 1 to 12 carbon atoms, X is chosen from an oxygen atom or a sulfur atom except when R.sub.2 and R.sub.3 represent a hydrogen atom, in which case X is an oxygen atom, Y is chosen from a hydrogen atom, a hydrocarbon-based radical comprising from 1 to 12 carbon atoms or a unit —C(O)R.sub.4, R.sub.4 being chosen from a hydrogen atom and a hydrocarbon-based radical comprising from 1 to 12 carbon atoms.

The invention concerns a synthesis process of a compound of the following formula (I) or one of the salts thereof,

##STR00001## wherein R represents a COOH, CH.sub.2OH or CHO group, comprising the step according to which the but-3-ene-1,2-diol (BDO) is subjected to an oxidation in the presence of a catalyst, said catalyst comprising an active phase based on at least one noble metal selected from palladium, gold, silver, platinum, rhodium, osmium, ruthenium and iridium, and a support containing alkaline sites.

The invention also concerns the application of this reaction to the preparation of bioavailable compounds of methionine used, in particular, in animal nutrition.