Abstract: A catalyst comprising vanadium phosphorus oxide combined with a thermally conductive material is particularly useful for the selective hydrocarbon oxidations (e.g., butane to maleic anhydride) and can be prepared by forming a suspension comprising a vanadium (IV) phosphate compound in a liquid medium (via hydrochloric acid digestion of V2O5 and H3PO4 in an aqueous solvent or via heating vanadium pentoxide with at least one substantially anhydrous unsubstituted alcohol having 1-10 carbon atoms, 1-3 hydroxyl groups free from olefinic double bonds to form a feed of vanadium pentoxide reduced to a valence between 4 and 4.6, and then contacting the feed with a solution of orthophosphoric acid and at least one unsubstituted alcohol), adding a thermally conductive material to the suspension under agitation at moderated temperature between 40° C. and 120° C., followed by drying, optionally but preferably washing and calcining (either in situ or ex situ) the material thus formed.

Abstract: A process for catalytically oxidizing H2S contained in a gas directly to sulphur containing the following steps: combining the H2S-containing gas with a gas containing free oxygen in an amount to produce an oxygen-enriched H2S-containing gas having O2/H2S molar ratio ranging from about 0.05 to about 15; and contacting the oxygen-enriched H2S-containing gas with a catalyst for selective oxidation of H2S to sulphur, wherein the catalyst includes a catalytically active phase combined with a silicon carbide-based support and wherein the active phase of the catalyst consists of at least one oxysulphide of at least one metal selected from the group consisting of iron, copper, nickel, cobalt, chromium, molybdenum and tungsten, at a temperature above the dew point of sulphur formed during H2S oxidation.

Abstract: A process for catalytically oxidizing the H.sub.2 S present at low concentration in a gas to sulphur wherein the gas together with a gas containing free oxygen in a quantity to provide and O.sub.2 to H.sub.2 S mole ratio ranging from 0.05 to 10 are contacted with a catalyst for selectively oxidizing H.sub.2 S to sulphur, the catalyst comprising a support based on silicon carbide associated with a catalytic active phase containing at least one transition metal such as Fe, Ni, Cr, Co, Cu, Ag, Mn, Mo, Ti, W or V, in a form of a metal compound and/or in the elemental state. Prior to treating the gas, the oxidation catalyst is subjected to an activation treatment which loads the active phase of the catalyst to provide maximum sulphurization of the metal of the catalyst. In an alternate embodiment, the oxidation of the H.sub.2 S is performed below the dew point of the sulphur. In another embodiment, the oxidation is performed at a temperature above the dew point of sulphur and in particular between 200.degree. C.