GB703491A - Improvements in or relating to production of oxygenated compounds from olefins - Google Patents

Abstract

Oxygenated products comprising aldehydes are obtained by contacting olefinic compounds, carbon monoxide, water, and hydrogen in an initial reaction zone with an iron group preferably a cobalt carbonylation catalyst at elevated temperature and pressure, passing the reaction mixture via a cooling zone to a gas-liquid high pressure separating zone where water and water-soluble cobalt compounds are separated from other liquid products and uncondensed gases, recycling at least a part of said water and water-soluble cobalt compounds to said initial zone thus maintaining a high concentration of active catalyst there and providing cooling, and passing the other aldehyde-containing liquid products to a decobalting zone where the cobalt catalyst is converted by heat treatment to insoluble cobalt compound and separated. Water is initially injected into said zone, but the flow of extraneous water may be cut back as reaction proceeds. The recycled water containing cobalt catalyst may be injected into the initial zone in the vicinity of the olefinic compound injection point and also at a plurality of points spaced in the direction of flow of said reaction products through said zone. In one modification, the cooled product stream, after separation only of uncondensed gases, may be passed to the lower portion of a liquid-liquid separating zone of which water fills at least the lower half, where water-soluble cobalt compounds are scrubbed out, and water from this zone is recycled to the initial zone. In a further modification the whole liquid product may be passed to a decobalter where the conditions are such that the cobalt catalyst in both phases is converted at least in part to other water-soluble cobalt compounds, e.g. cobalt formate, followed by separation of water and other liquid products. The usual olefines and catalysts are referred to.