A method of producing xylylenediamine by the hydrogenation of dicyanobenzene obtained by the ammoxidation of xylene in a high yield while prolonging the catalyst life. In the method, a molten dicyanobenzene from which compounds having a boiling point lower than that of dicyanobenzene have been removed but compounds having a boiling point higher than that of dicyanobenzene are not removed is dissolved in a solvent containing liquid ammonia. By this dissolution, at least part of dicyanobenzene polymers precipitates as insolubles. The precipitates are removed by a solid-liquid separation. By subjecting the resulting solution containing the dicyanobenzene polymers in a reduced amount to hydrogenation, xylylenediamine is produced in a high yield and the life time of hydrogenation catalyst is prolonged.
一种通过将二
甲苯氨氧化产生的二
氰基苯经氢化反应制备
对二甲苯二胺的方法,能够高产率地生产,同时延长催化剂的寿命。该方法中,将已去除沸点低于二
氰基苯的化合物但未去除沸点高于二
氰基苯的化合物的熔融二
氰基苯溶于含有液
氨的溶剂中。通过这种溶解,至少部分二
氰基苯聚合物沉淀为不溶性物质。通过固液分离去除沉淀物。将含有少量二
氰基苯聚合物的产物溶液进行还原反应,可以高产率地制备
对二甲苯二胺,并延长氢化催化剂的使用寿命。