1，6-六亚甲基二氨基甲酸甲酯液相催化分解反应研究

Liquid-phase Catalytic Decomposition Reaction of 1,6-Hexamethylene Dimethylurethane

对1，6-六亚甲基二氮基甲酸甲酯（HDC）液相催化分解制备1，6-六亚甲基二异氰酸酯（HDI）反应进行了研究。考察了多种催化剂、热载体以及反应条件对HDC分解反应性能的影响，确定了适宜的热载体为环烷油，适宜的催化剂为锌粉。HDI收率最高可达80．3％。但从温度控制、热载体带出、稳定性等方面综合考虑，较优反应条件：温度为260℃，压力为8．0kPa，此时HDI的收率为71．3％。考察了催化剂和热载体的重复利用情况。

This paper studied on the reaction of 1,6-hexamethylene dimethylurethane cleavage to 1,6-hexamethylene diisocyanate. The effects of catalysts, heat carriers, reaction conditions, reuse of catalyst and heat carrier on the yield of HDI were investigated. Naphthenic oil which was the best heat carrier and zinc which was the best catalyst were determined. The highest yield of HDI was 80.3%, but comprehensively considered on the temperature control, carryover of heat carrier, stability and so on. Optimal conditions： temperature was 260 ℃, pressure was 8.0 kPa, the yield of HDI was 71.3%. The recycle of catalysts and heat carriers were also investigated, and the reaction mechanism were preliminary analyzed.