Patent GB-735352-A (GB)
Title: Improvements in or relating to the synthesis of oxygenated organic compounds from olefins, carbon monoxide and hydrogen
IPC: C07C27/22
Filed: 1952-11-26
Abstract: Cobalt is recovered from a cobalt-contaminated aldehyde product of an Oxo-synthesis by contacting the product with an aqueous solution of a carboxylic acid whereby the cobalt is converted into water-soluble compounds containing both anionic and cationic cobalt, separating an aqueous solution containing the water-soluble compounds and converting the anionic cobalt therein to the cationic form, and recovering the cobalt in the form of an oil-soluble cobalt soap suitable for use in an Oxo-synthesis.  The Oxo-synthesis is effected under conventional conditions.  Anionic cobalt may be converted to the cationic form by treating the solution containing both forms with an oxidizing agent such as air at about 50-200 DEG  F. and at a pH maintained at at least 7.0, preferably 7-11.5 with an alkali metal hydroxide the anionic cobalt being thus converted to insoluble compounds which are converted to cobaltous compounds on acidification of the solution with e.g. sulphuric acid.  In this treatment cobaltous cobalt is precipitated as the hydroxide in the alkaline solution but redissolves on the addition of acid.  The solution containing cobaltous cobalt may then be treated with fatty acids, e.g. oleic or naphthenic, to give solutions of catalysts to be used in the synthesis.  The cobalt solution may be heated with oleic and/or sodium oleate in the presence of the olefine to be converted to give a catalyst layer on stratification.  Alternatively oleic acid may be used for the acidification of the precipitated cobalt. Carboxylic acids specified are formic, propionic and acetic the latter being preferred.  During treatment with carboxylic acid the temperature should not exceed 200 DEG  F. and is preferably about 150-185 DEG  F.  After stratification traces of cobalt may be removed from the aldehyde layer by washing with water at about 165 DEG  F. The wash water may be recycled to the mixer as a diluent for the acid stream.  The aldehyde may be hydrogenated in the usual fashion.  An illustration of suitable apparatus is provided together with experiments which show the presence of anionic and cationic cobalt in solutions obtained by treating aldehyde product with aqueous acetic acid; the incomplete recovery of cobalt as a salt of a fatty acid by a double decomposition reaction without prior oxidation; and the conversion of anionic and cationic cobalt into the cobaltous form by treatment of the acid decobalter aqueous layer with air either at a pH of about 10 the precipitated cobalt being redissolved with sulphuric acid or at 100-150 DEG  F. and a pH of 5-6 with the addition of an aqueous solution of a fatty acid salt obtained by treating Oxo alcohol bottoms with an alkali hydroxide at 500 DEG  C. Specification 702,950 is referred to.ALSO:Cobalt is recovered from a cobalt-contaminated aldehydic product of an Oxosynthesis by contacting the product with an aqueous solution of a carboxylic acid whereby the cobalt is converted into water-soluble compounds containing both anionic and cationic cobalt, separating an aqueous solution containing the water-soluble compounds and converting the anionic cobalt therein to the cationic form, and recovering the cobalt as an oil-soluble cobalt soap suitable for use in an Oxo-synthesis. Anionic cobalt may be converted to the cationic form by treating the solution containing both forms with an oxidizing agent such as air at about 50-200 DEG  F. and at a pH maintained at at least 7.0, preferably 7-11.5, with an alkali metal hydroxide the anionic cobalt thus being converted to insoluble compounds which are converted to cobaltous compounds on acidification of the solution with e.g. sulphuric or hydrochloric acids.  In this treatment cobaltous cobalt is precipitated as the hydroxide in the alkaline solution but redissolves on the addition of acid.  The solution containing cobaltous cobalt may then be treated with fatty acids, e.g. oleic or naphthenic acids, to give solutions of cobalt soaps for use as catalysts in the Oxosynthesis.  The cobalt solution may be heated with oleic acid or sodium oleate in the presence of the olefine to be converted to give a layer containing cobalt oleate on stratification.  Alternatively oleic acid may be used for the acidification of the precipitated cobalt.  Carboxylic acids specified are formic, propionic and acetic the latter being preferred.  During treatment with aqueous carboxylic acid solutions the temperature should not exceed 200 DEG  F. and is preferably about 150-185 DEG  F. After stratification traces of cobalt may be removed from the aldehyde layer by washing with water at about 165 DEG  F.  The wash water may be recycled to the mixer as a diluent for the acid stream. An illustration of suitable apparatus is provided together with experiments which show the conversion of anionic and cationic cobalt into the cobaltous form by treatment of the acid decobalter aqueous layer with air either at a pH of about 10 the precipitated cobalt being redissolved with sulphuric acid or at 100-150 DEG  F. and a pH of 5-6 with the addition of an aqueous solution of a fatty acid salt obtained by treating Oxo alcohol bottoms with an alkali hydroxide at 500 DEG  C.  Specification 702,950, [Group IV (b)], is referred to.