Process for the activation of zeolitic catalysts containing titanium and their use in oxidation reaction reactions

Oxidation processes of organic substrates with hydrogen peroxide or compounds capable of producing it under the reaction conditions, characterised in that said oxidation process consists in the ammoximation of carbonyl compounds carried out in the presence of zeolitic catalysts containing titanium having formula (I)

• xTiO2(1-x)SiO2 (I)
• wherein x ranges from 0.0001 to 0.4, said catalyst being obtained through a process which consists in subjecting the catalyst to treatment with an aqueous and/or aqueous-organic solution of an ammonium salt of a mono-, bi-, tri-, tetra-carboxylic acid, linear or branched, with a total number of carbon atoms ranging from 2 to 20, having general formula (II):
• 2
• wherein one of the R groups is a carboxyl whereas the other R groups, the same or different, can be selected from hydrogen, hydroxyl, ether, ester, carbonyl, carboxyl, amine, amide, vinyl, hydro-halogen, nitrile, hydro-sulfide, sulfonic, phosphonic groups, etc.;
• or they can be selected from alkyl, cycloalkyl, alkylcycloalkyl, aromatic, alkylaromatic, aralkyl and heteroaromatic groups, in turn substituted with one or more atoms or groups selected from hydrogen, hydroxyls, carboxyls, halogens, alkoxides, amines, esters, amides, vinyls, nitriles, hydroxyls, hydro-sulfides, carbonyls, etc.;
• the central carbon atom of general formula (II) may or may not belong to a cycle, which can be saturated or unsaturated, hetero-aromatic with one or more hetero-atoms selected from N, O, S, or non-hetero-aromatic;
• in the case of a cyclic substituent in formula (II), two adjacent R groups are immediately bound to the central carbon and contemporaneously belong to the cycle;
• this treatment is carried out for a time ranging from 0.2 to 5 hours, at concentrations of ammonium salt ranging from 0.2 to 10% by weight and is followed by the separation of the catalyst by filtration and its calcination at temperatures ranging from 300 to 650° C. for a period of time ranging from 1 to 6 hours.