一种以煤为原料同时制备均苯四甲酸和对苯二甲酸的方法,首先在高压釜中加入氢氧化钾、煤样和蒸馏水进行反应,反应后冷却取出氧化产品,过滤掉不溶残渣,滤液用浓硫酸酸化使水溶酸完全游离,处理后溶液用丁酮萃取,萃取液经真空蒸发回收丁酮,浓缩物再经真空干燥,得到水溶酸,再将水溶酸在硫 A method for preparing pyromellitic acid and terephthalic acid simultaneously with coal as the raw material comprises the following steps: firstly, adding potassium hydroxide, coal sample and distilled water into an autoclave to react, cooling the reaction product to remove the oxidation product, filtering out the insoluble residue, Acidification with concentrated sulfuric acid to completely dissolve the water-soluble acid, after treatment, the solution was extracted with methyl ethyl ketone, the extract was evaporated to dry butanone, the concentrate was dried in vacuo to give water-soluble acid, and then water-soluble acid in the sulfur