A carbonylation process for making acetic acid uses a metallic co-catalyst composition effective as a rhodium stabilizer and rate promoter at molar ratios of metal/rhodium of from about 0.5 to 30. A preferred process includes: (a) reacting methanol with a carbon monoxide feedstock in a rhodium-based catalytic reaction mixture having: (i) a rhodium catalyst metal, (ii) methyl iodide maintained from about 1 to 20 weight percent, (iii) a lithium iodide co-catalyst, (iv) a metallic co-catalyst composition, (v) water maintained from 0.1 weight percent to less than 8 weight percent, (vi) methyl acetate maintained from about 0.5 to about 30 weight percent, and (vii) acetic acid; (b) flashing crude acetic acid from the reaction mixture; and (c) purifying the crude acetic acid. This process achieves stability and a STY greater than 10 mol/L/hr, with substantially less than a theoretically equivalent inorganic iodide content corresponding to the metallic co-catalyst and lithium iodide.
一种羰基化过程用于制造
乙酸,该过程使用一种
金属辅催化剂组成,其在
金属/
铑的摩尔比为0.5至30时有效作为
铑稳定剂和速率
促进剂。首选的过程包括:(a)在具有以下组分的
铑基催化反应混合物中将
甲醇与一种
一氧化碳原料反应:(i)
铑催化剂
金属,(ii)维持在1至20重量%之间的甲基
碘,(iii)
碘化
锂辅催化剂,(iv)
金属辅催化剂组成,(v)维持在0.1重量%至少于8重量%的
水,(vi)维持在0.5至约30重量%的
乙酸甲酯,以及(vii)
乙酸;(b)从反应混合物中闪蒸原油
乙酸;和(c)纯化原油
乙酸。该过程实现了稳定性和STY大于10 mol/L/hr,且其无机
碘化物含量明显低于相应的
金属辅催化剂和
碘化
锂的理论等效含量。