Process Economics Program Report 146
Bulk Chemicals from Synthesis Gas
Published: June 1982
This report covers several emerging technologies which use synthesis gas as the principal feedstock for production of bulk chemicals. These chemicals include acetic anhydride, vinyl acetate, ethylene, and ethanol. Six processes are presented: two each for the manufacture of acetic anhydride and ethylene, and one each for the manufacture of vinyl acetate and ethanol.
Section 4 compares two routes to acetic anhydride. In the conventional route, carbon monoxide and methanol are reacted to give acetic acid. Part of the acetic acid is pyrolyzed to ketene which is then reacted with the remaining acetic acid to give acetic anhydride. In a second route, recently announced by Tennessee Eastman, methanol is esterified to methyl acetate. The methyl acetate is then reacted with carbon monoxide to form acetic anhydride.
A new process to vinyl acetate is presented in Section 5. It entails reaction of synthesis gas with methyl acetate derived by esterification of methanol as in the above process. The process economics is compared with that for the conventional process to vinyl acetate from ethylene and acetic acid.
Sections 6 and 7 compare two routes to ethylene. Section 6 concerns the manufacture of ethylene by a direct Fischer-Tropsch synthesis from synthesis gas. Section 7 concerns the manufacture of ethylene from methanol in the presence of a zeolite catalyst. The economics for both processes when coal is used as the basic feedstock are compared with the economics for the conventional process to ethylene from gas oil.
Section 8 evaluates a route to ethanol directly from synthesis gas, with a copper-cobalt catalyst, in a manner similar to that used in the manufacture of methanol. It is compared with the conventional route to ethanol by catalytic hydration of ethylene.