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综述了3,3’,4,4’-二苯甲酮四甲酸二酐的应用及其制备和提纯的方法。第一种是硝酸法,用邻二甲苯和乙醛作原料,硫酸作催化剂在较低温度下进行缩合反应合成3,3’,4,4’-四甲基二苯乙烷,采用硝酸分2步对其进行氧化得到3,3’,4,4’-二苯甲酮四羧酸(简称酮酸);第二种是采用液相空气氧化法制备酮酸。同时还分别介绍了提纯酮酸及酮酐的方法(1)醋酐法;(2)丙酮重结晶法;(3)硅胶吸附法;(4)乙醇洗涤法;(5)乙醚洗涤法;(6)升华法。
The application of 3,3 ’, 4,4’-benzophenone tetracarboxylic dianhydride and its preparation and purification methods are reviewed. The first is the nitric acid method, with o-xylene and acetaldehyde as raw materials, sulfuric acid as a catalyst at a lower temperature condensation reaction synthesis 3,3 ’, 4,4’-tetramethyl diphenyl ethane, the use of nitric acid points 2-step oxidation of 3,3 ’, 4,4’-benzophenonetetracarboxylic acid (referred to as keto acid); the second is the use of liquid air oxidation of keto acid. At the same time, the methods of purifying ketoacids and ketones are also introduced respectively. (1) The method of acetic anhydride; (2) Acetone recrystallization; (3) Silica gel adsorption; (4) Ethanol washing; 6) sublimation method.