Abstract
A method to save the alkali consumption in the production of benzene carboxylic acids from coal by the high pressure oxygen oxidation process was demonstrated.
Pulverized coal, suspended in water, was oxidized by oxygen in an autoclave at 180°C without alkali. After purging off the gaseous product from the autoclave relatively small amount of NaOH (NaOH/coal=1.5) and oxygen were added and the secondary oxidation was carried out at 240°C.In this stepwise oxidation process the yield of benzene carboxylic acids based on the amount of NaOH used was larger than that in the process previously reported.
The relation between the composition of benzene carboxylic acids and the rank of coal was considered and the direction of choice of coal as the starting material of this process was discussed.
