Vapor Phase Carbonylation of Methanol to Acetic Acid with Pressurized Fluidyzed Bed Reactor

这是发现a nickel on active carbon (Ni/ a.c.) catalyst exhibited a high activity andselectivity for the vapor phase carbonylation of methanol to acetic acid under moderatelypressurized (5- 30atm) and heated (200- 300c) conditions. The 2.5% Ni/ a.c. catalyst gave；100% methanol conversion and 97% acetic acid yieldin the presence of methyl iodide promoter and excess carbon monoxide. the reaction path wasclarified as followsThe yield of each product as a function of time factor was well simulated by calculating numericallythe rate of each unit reaction. the Ni/ a.c. catalyst was stable during the reactionwhich exhibited a half life time of 50 days. The decrease in The catalytic activity notattributed to the vaporization of nickel from the catalyst but to the deposition of tarry materialon the catalyst, which caused the plugging of micro-pores in the catalyst.A fluidized bed reactor，可操作下pressurized conditions with a gas-recyclewas built and subjected to the methanol carbonylation. A remarkable flat temperature profile wasattained in the catalyst bed during the reactionwhich gave a result of more than 1kg -acetic acid/Kg-cat.h with a selectivity of 99% carbonylatedproducts. The level is even superior to of a fixed bed reaction, is sufficient forindustrialization.It was also found that hydrogen in the feed gas, which commonly exist in CO，remarkably promotes the reaction with little change in the产品选择。the hydrogen did notpromote any particular reaction but promoted all reactions in the reaction network. However，little hydrogen in the gas phase not incorporated in the product，suggesting the promotional effect being not in the direct way but in the indirect way. thefeasibility study of the present process suggests that it is competitive to a presently operating过程which uses rhodium catalyst。

It was found that a nickel on active carbon (Ni/A.C.) catalyst exhibited a high activity and selectivity for the vapor phase carbonylation of methanol to acetic acid under moderately pressurized (5-30 atm) and heated (200-300 ゜C) conditions. The 2.5% Ni/A.C. catalyst gave ; 100% methanol conversion and 97% acetic acid yield, in the presence of methyl iodide promoter and excess carbon monoxide. The reaction path was clarified as follows: The yield of each product as a function of time factor was well simulated by calculating numerically the rate of each unit reaction. The Ni/A.C. catalyst was stable during the reaction, which exhibited a half life time of 50 days. The decrease in the catalytic activity was not attributed to the vaporization of nickel from the catalyst but to the deposition of tarry material on the catalyst, which caused the plugging of micro-pores in the catalyst.A fluidized bed reactor, which was able to be operated under pressurized conditions with a gas-recycle, was built and subjected to the methanol carbonylation. A remarkable flat temperature profile was attained in the catalyst bed during the reaction, which gave a result of more than 1 Kg-acetic acid/Kg-cat.h with a selectivity of 99% carbonylated products. The level is even superior to that of a fixed bed reaction and is sufficient for industrialization.It was also found that hydrogen in the feed gas, which commonly exist in CO, remarkably promotes the reaction with little change in the product selectivity. The hydrogen did not promote any particular reaction but promoted all reactions in the reaction network. However, little hydrogen in the gas phase was not incorporated in the product, suggesting that the promotional effect being not in the direct way but in the indirect way.The feasibility study of the present process suggests that it is competitive to a presently operating process which uses rhodium catalyst.