Chapter 10
Downloaded by UNIV OF CALIFORNIA SAN DIEGO on September 1, 2015 | http://pubs.acs.org Publication Date: December 16, 1987 | doi: 10.1021/bk-1987-0328.ch010
Production of Vinyl Acetate from Methanol and Synthesis Gas Nabil Rizkalla1 and Alan Goliaszewski
The Halcon SD Group, Inc., Montvale, NJ 07645 This report describes a process to produce vinyl acetate with high selectivity from exclusively methanol, carbon monoxide, and hydrogen. The simplest scheme for this process involves esterifying acetic acid with methanol, converting the methyl acetate with syn gas directly to ethylidene diacetate and acetic acid, and finally, thermal elimination of acetic acid. Produced acetic acid is recycled. Each step proceeds in high conversion and selectivity. The single step conversion of methyl acetate to ethylidene diacetate is catalyzed by either a palladium or rhodium compound, a source of iodide, and a promoter. The mechanism is described as involving the concurrent generation of acetaldehyde and
acetic anhydride which subsequently react to form ethylidene diacetate.
An alternative to this scheme
involves independent generation of acetaldehyde by reductive carbonylation of methanol or methyl acetate, or by acetic anhydride reduction. The acetaldehyde is then reacted with anhydride in a separate step. Mixtures of carbon monoxide and hydrogen have proven to be versatile starting materials for the chemical industry. Certain processes involving the conversion of syn gas to simple organic chemicals have been demonstrated as selective and efficient.
One example is meth-
anol, produced in high selectivities by passing carbon monoxide and
hydrogen over a heterogeneous catalyst. Other examples of commercial processes are acetic anhydride and acetic acid. Patents cover other processes including acetaldehyde, ethanol, and ethylene glycol. At first glance, vinyl acetate is an unlikely candidate to be prepared exclusively from syn gas. Most vinyl acetate is presently produced by the palladium-catalyzed reaction of acetic acid and ethylene that involves subsequent reoxidation of reduced palladium. This report describes an alternative process for vinyl acetate utilizing syn gas as feedstock, thus avoiding the necessity for ethylene (see figure 1). Of course, at this time of plummetting oil prices, a route utilizing syn gas cannot 'Current address: 415 Faletti Circle, River Vale, NJ 07675 0097-6156/87/0328-0136$06.00/0
© 1987 American Chemical Society In Industrial Chemicals via C1 Processes; Fahey, D.; ACS Symposium Series; American Chemical Society: Washington, DC, 1987.
Downloaded by UNIV OF CALIFORNIA SAN DIEGO on September 1, 2015 | http://pubs.acs.org Publication Date: December 16, 1987 | doi: 10.1021/bk-1987-0328.ch010
1 0. RIZKALLA AND GOLIASZEWSKI
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In Industrial Chemicals via C1 Processes; Fahey, D.; ACS Symposium Series; American Chemical Society: Washington, DC, 1987.
146
INDUSTRIAL CHEMICALS VIA C, PROCESSES
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