GB1030003A - - Google Patents

Abstract

Cyclohexyl phenyl ketone is made by reacting a mixture of benzene and hexahydrobenzoic acids at 280 DEG to 480 DEG C. in the presence of a catalyst comprising the manganous salts of the said acids. The catalyst is made by dissolving manganous oxide, or manganese carbonate, in a mixture of the acids. Preferably for 2 moles of acids there are present 1.1 to 1.3 mols. of manganous oxide. The catalyst may also be made by double decomposition from the two acids and appropriate manganese salts. Other metal oxides, e.g. magnesium or lithium oxide, may be present and, if so, an additional amount of the acids, equivalent to the quantity of inert oxide, should also be present. Preferably there is an excess of 0.1-0.3 moles of hexahydrobenzoic acid in relation to the benzoic acid. Preferred temperatures are 330 DEG to 370 DEG C. Activity of the catalyst may be maintained by passing steam through the reaction mixture. Oxidation of the catalyst is prevented by passing small quantities of hydrogen through the reaction mixture. Sub-, normal- or elevated-pressures may be adopted. Examples are provided.ALSO:A catalyst containing manganese, in the manganous form, is made by dissolving manganese oxide, or carbonate, in a mixture of hexahydrobenzoic and benzoic acids or by double decomposition from the acid mixture and appropriate manganese salts. Preferably for each two moles of acid mixture there are present 1.1 to 1.3 moles of manganous oxide. Inert oxides e.g. magnesium and lithium oxides, may be present and if so, an additional quantity of the acids, equivalent to the amount of inert oxide, should also be present. Catalytic activity may be maintained by effecting the reaction in the presence of steam and/or hydrogen.