| 摘要 |
<p>Dialkyl carbonates can be prepared by reaction of carbon monoxide with alk yl nitrites in continuous gas phase reaction, in which a platinum metal halide catalyst on aluminium oxides, aluminium oxide hydrates or aluminium hydroxides as support and, if desired, an additive comprising an antimony, bismuth, aluminium, copper, vanadium, niobium, tantalum, tin, iron, cobalt, nickel compound or a mixture of a plurality thereof on this catalyst are used and hydrogen halide is replaced during the course of the reaction batchwise or continuously in at least the amount which is discharged from the reactor together with the reaction mixture. This results in the formation of dialkyl carbonates in almost quantitative selectivity, while the corresponding dialkyl can not in most cases be detected. The abovementioned supports are characterised by a BET surface area of more than 1 m2/g.</p> |
