GB190219178A - A Process for Oxidising Organic Compounds. - Google Patents

Abstract

19,178. Imray, O., [Farbwerke vorm. Meister, Lucius, & Br³ning]. Sept. 1. Alcohols; aldehydes; amines; bromo, chloro, iodo, and nitro compounds, organic; carboxylic acids; dyes, artificial; hydrocarbons; ketones; phenols; quinones; sulphonic acids.-Relates to the use of cerium oxides or salts or mixtures of oxides &c. of metals of the cerium group for oxidizing hydrocarbons and other organic compounds. Two processes are described. In one, the oxidation is effected in an electrolytic bath, the oxides &c. acting merely as carriers of oxygen and being successively oxidized and reduced, and in the other the oxygen of the oxidizing-body affects the oxidation. The oxidizing-bodies may be obtained from cerite or by heating, in air, the byeproducts from the manufacture of incandescent mantles, the presence of neodymium and praseodymium being rather advantageous. In one process, applied to the oxidation of toluene to benzaldehyde, tolylphenylmethane, and anthraquinone, m-xylene to m-tolylaldehyde, o-nitrotoluene to o.nitrobenzoic acid, or to the oxidation of other hydrocarbons or their substitution derivatives, cerinm dioxide is added in small quantities to a heated mixture of toluene and sulphuric acid at a temperature of 60‹ C. and the temperature raised to 90‹ C. when all the oxide is added. The reaction is completed when all the brown cerium oxide has been converted into white sulphate. In another process, by which anthracene is oxidized to anthraquinone, naphthalene to naphthoquinone or phthalic acid, anthracene disulphonic acid to anthraquinone disulphonic acid, dichloranthracene to anthraquinone, tetrachlornaphthalene to phthalic acid, tetraalkylated diamidodiphenyl methanes to the corresponding hydrols, leuco bases of triphenylmethane dye-stuffs to the corresponding dye-stuffs &c., the substance to be oxidized is slowly run into a mixture of ceric sulphate or nitrate, or ceric ammonium nitrate, and sulphuric or other acid, the temperature of the mixture being gradually raised. Dinitro-alpha-naphthol is oxidized even in the cold. In the electrolytic process the substances are introduced into a lead-lined cell containing sulphuric acid and a small quantity of a cerium salt. The electrode is preferably surrounded by a filter cloth or other porous diaphragm. This process is applied to the oxidation of anthracene to anthraquinone, naphthalene to naphthoquinone or phthalic acid, and phenanthrene to phenanthraquinone or benzoic acid. The processes are also applicable to nitro, sulpho, oxy, halogen, &c. substitution products of hydrocarbons. According to the Provisional Specification, an alkaline solution of a cerium salt may be used. Thus, amidophenol disulphonic acid or m-phenylenediamine is oxidized in the cold, and naphthalene when heated is transformed into phthalonic and phthalic acids.