均四甲苯气相氧化制均苯四酸二酐

Preparation of Pyromellitic Dianhydride by Gas phase Catalytic Oxidation of 1, 2, 4, 5-Tetramethyl Benzene

均四甲苯为原料,经过气相催化氧化制得均苯四酸二酐(简称PMDA)的技术开发,已通过小试和生产单管试验,研制出新的V-Ti体系五元组份催化剂8612和新型热管反应器,在440—460℃、空速6000—7000h^(-1)和催化剂负荷为90—100g(均四甲苯)/b·l(催化剂)下,固酐重量收率为90—100％(w)(均四甲苯),均酐纯度达到97—98％。

This paper presents a method by which pyromellitic dianhydride (PMDA) can be made from the catalytic oxidation of tetramethyl benzene. The method has already been proved practicable through small-scale test and single tube heat exchange test. A five-component V-Ti system catalyst no. 8612, is developed and anew type heat pipe reactor is installed, with these, PMDA with a yield of 90—100%(w) and a purity of 97—98% can be obtained from the 1, 2, 4, 5-tetramethyl benzene under the optimum conditions of temperature, 400—460℃; space velocity, 6000—7000h^(-1); and catalyst load, 90—100g/h·l.