25. ALLEN, C. F. H. The Oxo Process. Syn. Org. Chem., Eastman Kodak Co., vol. 18, No. 3, 1946; U. O. P. Co. Lib. Bull., vol. 22, No. 5, 1947, p. 20.
Oxo process developed in Germany produces straight-chain aldehydes and ketones from olefins and water gas, the former predominating. The use of hydrocarbons terminating in =CH2 favors production of aldehydes. For example, if C2H4 is used, the products are propionaldehyde and diethyl ketone, the former being 70% of the total. The product from unsaturated hydrocarbons containing 11-17 C atoms has been the basic starting material. The reaction can be carried out in batches or continuously. Pressures used are about 150 atm. with temperatures up to 180°. After partial conversion and separation of the oxygenated fraction by distillation, the residue is made up with new gas and recirculated. The catalyst consists of Co, Th, and Mg carbonates on kieselguhr suspended in Diesel oil. The catalyst is not sensitive to S, so removal of S compounds from the water gas is not necessary. Possibilities of the process are great. The carbonyl compounds formed can be converted into other substances by known chemical processes. For example, reduction in presence of a Raney Ni catalyst gives the corresponding alcohols. These can be sulfated to produce the modern detergents. The development is only beginning, however, and many technical difficulties remain to be overcome.
ALLEN, J. G. See abs. 1477.