Abstract: A method of producing aliphatic and cycloaliphatic diols by catalytic hydrogenation of dicarboxylic acid esters by the use of a copper chromite catalyst in which the copper content (calculated as CuO) is 40-47 wt. %, and the chromium content (calculated as Cr.sub.2 O.sub.3) is 40-47 wt. %, and barium is also present in the amount of up to 10 wt. % (calculated as BaO) under mild temperature and pressure conditions is disclosed. The method produces diols without the formation of high boiling materials and does not require purification of the product diols by overhead distillation.

Abstract: A process for the manufacture of phthalic anhydride by oxidation in the gas phase of an o-xylol naphthalene mixture. By producing a solution of 1 to 80 parts by mass naphthalene in 99 to 20 parts by mass o-xylol at a temperature of 0.degree. to 80.degree. C., storing the solution at that temperature, heating the solution only shortly prior to the reaction to 110.degree. to 180.degree. C., atomizing the heated solution into a hot airflow, passing the heated solution over metal oxide catalysts in the gas phase and collecting phthalic anhydride product, a problem-free manufacture of phthalic anhydride is attained.