abstract |
Acetaldehyde is produced by reacting methanol with hydrogen and carbon monoxide at elevated temperature and pressure in the presence of a catalyst comprising cobalt, an iodide or a bromide and one of the elements arsenic, antimony or bismuth, either in the form of the free element or a compound thereof, and in the additional presence of one or more of the following additives:n (i) an inert liquid such as chlorobenzene, decanoic acid, a polydimethylsiloxane fluid or a methyl phenyl silicone fluid, (ii) an acid and/or an acid derivative such as acetic acid, acetic anhydride, propionic acid, phenylacetic acid, benzoic acid, methyl acetate or butyl acetate. (iii) an oxygen-containing organic compound such as 1,4-dioxane, tetrahydrofuran, di-n-propylether, diphenylether, acetone, acetaldehyde, n-propanol or n-butanol. (iv) a non-polar solvent such as an alkane, benzene or an alkyl-substituted benzene. n The presence of the additive suppresses by-product formation and thereby improves the yield and selectivity to acetaldehyde. |