GB268775A - Improvements in the manufacture and production of hydrocarbons or oxygen derivativesthereof - Google Patents

Abstract

268,775. I. G. Farbenindustrie Akt.- Ges. April 3, 1926, [Convention date]. Hydrocarbons; carboxylic acids and acid anhydrides; phenol; formaldehyde; quinone.- Hydrocarbons or their oxygen derivatives are converted into lower hydrocarbons or their oxygen derivatives (in the latter case with the intermediate production of hydrocarbons) by subjecting them to heat treatment with an oxygen-containing gas in the presence of an oxidation catalyst and also to decarboxylation at an elevated temperature, in the presence or absence of water vapour, using catalysts capable of splitting off carbon dioxide. The oxidation and decarboxylation are effected successively in either order, with or without repetition of any treatment, but in any case without separation of the intermediary products. The order of the operations determines the results obtained. For the catalytic oxidation, oxygen-supplying gases such as carbon dioxide and water vapour may be used instead of or along with the oxygen-containing gas; whilst in the decarboxylation of a dicarboxylic acid anhydride into a monocarboxylic acid, water must be present. By the process, for example, acenaphthene is converted into formaldehyde, with formation of naphthalic anhydride, naphthoic acid, naphthalene, phthalic anhydride, benzoic acid, benzene, benzoquinone, maleic anhydride, acrylic acid and ethylene as intermediary products. Starting from naphthalene or its substitution products such as alkyl- or hydroxynaphthalenes, in a similar manner phthalic anhydride, benzoic acid, benzene, benzoquinone, maleic anhydride, acrylic acid, ethylene and formaldehyde may be obtained. Salicylic acid mav be converted into phenol, benzoquinone, maleic anhydride, acrylic acid, ethylene and formaldehyde. According to the examples, (1) benzene is obtained by passing air and naphthalene vapour over heated vanadium pentoxide, and then bringing the cooled reaction mixture into contact with a catalyst containing the oxides of cadmium and aluminium; the naphthalene may be replaced by methylnaphthalene and water vapour may be present; (2) maleic anhydride, together with some benzoquinone, results when air and naphthalene vapour are passed over heated vanadium pentoxide, the products brought into contact with a catalyst containing the oxides of zinc, cadmium and aluminium, and then, if desired. with admixture of preheated air, passed over heated vanadic and salts. Specification 262,101 is referred to. The Specification as open to inspection under Sect. 91 (3) (a) states that the oxidation and the decarboxylation may be effected simultaneously. It refers also to the treatment of nitronaphthalenes. This subject-matter does not appear in the Specification as accepted.