【摘要】 进行了煤氧化产物煤酸(水溶酸WSA)钾在催化剂碳酸镉的存在下,异构化制对苯二甲酸(TPA)的研究。主要考察了催化剂用量、二氧化碳初压、反应温度和反应时间对TPA产率的影响。结果表明,在催化剂存在下煤酸可以转化成TPA。单独煤酸钾异构化时,较佳反应条件:温度430℃～450℃,压力4 0MPa,催化剂CdCO3用量4%,反应时间2h。煤酸钾与苯甲酸(BA)钾混合异构化时,较佳反应条件与单独煤酸钾时基本相同。单独煤酸钾在较佳条件下异构化时,粗TPA产率达34%左右,相当于根据其中有效成分苯多羧酸(BPCA)计算的理论产率的75%左右,选择性较好。煤酸钾加苯甲酸钾在较佳条件下异构化时,粗TPA产率可达68%,扣除假定BA自身岐化生成TPA理论产量之后,则煤酸的TPA产率高达70%,比煤酸单独异构化TPA产率(34%)高1倍。粗TPA经精制可得纯度99%以上的精TPA。更多还原

【Abstract】 Terephthalic acid can be obtained in the presence of a catalyst CdCO3 by isomerization of potassium salt of coal acid (watersoluble acids, WSA) produced from coal oxidation Effects of the amount of catalyst, initial pressure of CO2, reaction temperature and reaction time were investigated It was confirmed that WSA can be converted to terephthalic acid in the presence of a catalyst In case of isomerizing the potassium salt of coal acids alone, the optimum conditions of isomerization were found to be: temperature 430?℃～450?℃, initial pressure of CO2 40?MPa, catalyst CdCO3 4% and reaction time 2?h Such optimum conditions were similar to those of the isomerization by a mixture of potassium coal acids (WSA) and potassium benzoic acid (BA) The yield of crude TPA by isomerization of potassium salt of coal acid was about 34%, which was equivalent to 75% of BPCA(theoretical yield), and was the effective composition of WSA It has shown that the selectivity was good The yield of crude TPA was about 68% if isomerization was carried out wita mixture of potassium salts of coal acid and benzoic acid at its optimum conditions The yield of TPA was as high as 70% after being deducted from the theoretical yield of BA dismutation, and about two times of WSA isomerization alone The purity of the refined TPA was ≥ 99%更多还原