METHOD OF PREPARING ACETIC ACID BY CARBONYLATION Russian patent published in 2000 - IPC

FIELD: chemical industry. SUBSTANCE: acetic acid is prepared by carbonylation of methanol and/or reactive, derivative thereof in liquid phase in the presence of iridium carbonylation catalyst, methyl iodide cocatalyst and promoter. Water content in liquid reaction mixture is maintained at not higher than 6.5 wt % of water, concentration of methyl acetate within 1-35 wt % and concentration of methyl iodine within 4-20 wt %. Promoter is selected from group consisting of ruthenium, osmium, rhenium, cadmium, mercury, zinc, gallium, indium, and tungsten. Promoter to iridium molar ratio is (0.5-15):1. Concentration of iridium catalyst is preferably 400-3000 ppm, and concentration of rhutenium promoter is 400-4000 ppm. Use of improved catalyst gives higher reaction rate and greater yield of acetic acid. EFFECT: more efficient preparation method. 12 cl, 8 dwg, 1 tbl