1977 年 19 巻 2 号 p. 109-118
Stepwise synthesis of acetic acid from secondary butanol was studied. The oxidation of secondary butanol to methyl ethyl ketone and acetic acid with Co3O4-X and Rh2O3-X binary and ternary catalysts and the oxidation of methyl ethyl ketone to acetic acid with V2O5-X binary catalysts were studied. The reactions were carried out in the presence of water in a temperature range from 170° to 300°C.
Over the Co-V(9:1) and Rh-V (8:2) catalysts, secondary butanol formed with high conversion methyl ethyl ketone with selectivity of 80∼93% at 170∼230°C. Other primary and secondary alcohols gave aldehyde or ketone with selectivity of over 90%. Under more severe conditions, secondary butanol formed mainly acetic acid. For example, using the Co-V-Rh (75:25:2) catalyst, secondary butanol yielded 59% and 2% of acetic acid and methyl ethyl ketone, respectively, and it was not dehydrated to n-butenes1).
The V2O5-Cr2O3 (6:4) catalyst was found most selective among the V2O5-binary catalysts for oxidation of methyl ethyl ketone to acetic acid whose yield was 78% at 260°C. Under more moderate conditions, the yield of acetic acid was 88% with V2O5-Sb2O5 (4:6) catalyst.
As for the one step synthesis of acetic acid from n-butenes, good results were obtained with Co-V-Cr and Co-V-Al catalysts. With Co-V-Al (75:25:20) catalyst, the amount of acetic acid and total acid (acetic acid with other acids such as maleic acid) was obtained with selectivity of 90% at 50% conversion of n-butenes.