Catalyst for the dehydrogenation of C.sub.6 -C.sub.15 paraffins and to a process for making such catalysts

A catalyst for the dehydrogenation of C.sub.6 -C.sub.15 paraffins comprising, on an inorganic support, 0.01 to 5 wt. % of at least one platinum group metal, 0.01 to 5 wt. % of at least one of the elements tin, germanium and lead as a promoter and magnesium as a modifier, obtained by simultaneous introduction to the inorganic support of a soluble precursor of said platinum group metal, said promoter and said modifier from a common impregnation solution to thereby form an impregnated support, drying of the impregnated support, calcining said support at a temperature between 300.degree. C. and 700.degree. C. and subsequent reduction of said precursor in a hydrogen-containing gas at temperatures between 200.degree. C. and 700.degree. C., wherein said magnesium is present at a concentration by weight of 0.01 to 20 wt. % of the final catalyst.

A process for preparing a catalyst for the dehydrogenation of C.sub.6 -C.sub.15 paraffins, containing, on an inorganic support, 0.01 to 5 wt. % of at least one platinum group metal, 0.01 to 5 wt. % of at least one of the elements tin, germanium and lead as promoter and magnesium as a modifier, comprising simultaneously applying to the support a soluble precursor of the platinum group metal, promoter and modifier from a common impregnation solution, drying the support, calcining said support at temperatures between 300.degree. and 700.degree. C. and then reducing said precursor in a hydrogen-containing gas at temperatures between 200.degree. and 700.degree. C., wherein magnesium is at a concentration of 0.01 to 20 wt. % of the final catalyst as modifier and wherein said support has a bulk density of 0.25 to less than 0.5 g/cm.sup.3.