GB400384A - Improvements relating to the production of higher ketones - Google Patents

Abstract

Catalysts for the conversion of lower into higher aliphatic ketones with the aid of lower aliphatic primary alcohols consist of aluminium xide with or without magnesia or other alkaline earth metal oxide as main constituent with relatively small amounts of copper and/or silver or an oxide thereof, to which molybdenum trioxide may be added. The catalysts used in the examples are prepared by (1) impregnating alumina with copper formate and molybdenum trioxide or barium oxide, (2) spreading magnesium oxide and aluminium hydroxide with small quantities of copper and silver oxides, (3) impregnating alumina with copper formate, (4) mixing magnesium oxide with aluminium hydroxide and copper oxide; in each case, the product is heated with air and steam. Specifications 326,812, [Class 1 (i), Chemical processes &c.], and 364,134 are referred to.ALSO:Higher aliphatic ketones are prepared by subjecting a mixture of a lower aliphatic ketone with a lower aliphatic primary alcohol together with hydrogen or nitrogen to a temperature of 150-400 DEG C. in the presence of a catalyst consisting of aluminium oxide with or without magnesia or other alkaline-earth metal oxide as main constituent with relatively small amounts of copper and/or silver or an oxide thereof, to which molybdenum trioxide may be added. The reaction may be effected discontinuously in an autoclave, or by continuously passing the reactants over the catalyst at ordinary or increased pressure. Both the hydrogen and nitrogen are stated to act primarily as diluents, but when using hydrogen small amounts of higher primary alcohols are also formed. According to the examples, (1) methyl alcohol and acetone in equimolecular quantities are passed with at least an equal volume of nitrogen over a catalyst prepared by impregnating alumina with copper formate and molybdenum trioxide or barium oxide and treating with air and steam at 450 DEG C.; the product contains methylethyl ketone, diethyl ketone and high-boiling polysubstituted ketones; (2) a mixture of acetone (1,25 mols.), ethyl alcohol (1 mol.), and hydrogen (1,5 mols.) is passed over a catalyst prepared by kneading magnesium oxide and aluminium hydroxide with small quantities of copper and silver oxides and heating the mixture with air and steam; methylpropyl ketone, dipropyl ketone and high-boiling ketones are obtained, together with butyl and hexyl alcohol; an alternative catalyst is prepared by impregnating alumina with copper formate; (3) magnesium oxide is mixed with aluminium hydroxide and copper oxide and treated with air and steam at 400-500 DEG C., and over this catalyst is passed a mixture of acetone (3,0 mols.), ethyl alcohol (2,5 mols.) and hydrogen (3.2 mols.) under pressure; the products comprise methylpropyl ketone and dipropyl ketone, together with butyl alcohol, hexyl alcohol and higher alcohols (4) a mixture of acetone (2,5 mols.), butyl alcohol (2 mols.) and hydrogen (3 mols.) is passed under pressure over the catalyst used in (3); methylamyl ketone is the principal product, but heptyl alcohol, octyl alcohol and higher ketones and alcohols are also formed; (5) methylethyl ketone (2 mols.), ethyl alcohol (3 mols.) and hydrogen (3 mols.) are passed under pressure over the catalyst used in (3), giving rise to higher ketones, mainly C6 and C8, together with butyl alcohol, hexyl alcohol and higher alcohols; (6) higher ketones, mainly methylamyl ketone, result from the heat treatment of butanol and acetone with hydrogen in an autoclave in the presence of the catalyst employed in (3). Specifications 326,812, [Class 2 (iii), Dyes &c.], and 364,134 are referred to. The Specification as open to inspection under Sect. 91 describes the formation of higher ketones by catalytic interaction of a lower ketone with an aliphatic alcohol, in the presence or absence of a diluent gas. This subject-matter does not appear in the Specification as accepted.