Carbon Monoxide and Oxo-Alcohols
Pure carbon monoxide is a raw material for a number of organic chemicals such as acetic acid, phosgene, which is an intermediate for polyurethane manufacture, and formic acid (see Figure 7-6). The toxic nature of CO makes it difficult to store or transport. For safety, inventories are usually kept to a minimum. For these reasons pure carbon monoxide plants tend to be located close to the point of use of the product and are accordingly fairly small. Approximately 500kt/y of CO is used for producing acetic acid.
The term oxo-alcohols covers a range of higher alcohols, from C3-alcohol to C18 +. Lower alcohols (propanol, butanol, and pentanol) find usage as solvents. In the range C8 to C10 they are used as plasticizers. Higher alcohols (C12+) are required for the manufacture of synthetic detergents. Oxo-alcohols are manufactured by reacting olefins with syngas (50:50 H2:CO) to form aldehydes. The aldehyde is then hydrogenated with high purity hydrogen to produce the oxo-alcohol end product. World production of oxo alcohols is about 8100 kt/y, over half of which is produced in two countries alone, the United States and Germany.