ZnAlPO_4催化分解氨基甲酸酯制备六亚甲基-1,6-二异氰酸酯

INVESTIGATION ON THE CATALYTIC DECOMPOSITION OF DIMETHYLHEXANE-1,6-DICARBAMATE TO SYNTHESIZE HEXAMETHYLENE-1,6-DIISOCYANATE BY ZnAlPO_4

采用静态水热合成法制备了Zn负载量不同的ZnAlPO4多相催化剂,并通过XRD和XPS分别对其结构和组成进行了表征。通过对氨基甲酸酯热分解反应系统的分析和六亚甲基-1,6-二异氰酸酯(HDI)回收率的考察,自行设计并组装了六亚甲基二氨基二甲酸甲酯(HDC)液相热分解制HDI的反应装置,并利用此装置考察了在邻苯二甲酸二辛酯(DOP)作热载体,邻苯二甲酸二甲酯(DMP)作溶剂,反应温度523K,真空度0.09MPa,氮气流速100mL/min,进料速率10.00g/(g.h),ZnAlPO4/HDC(摩尔比)为1.0%的反应条件下,不同Zn负载量的ZnAlPO4催化HDC液相热分解制HDI的反应活性。实验结果表明:相对ZnO催化剂,ZnAlPO4具有更高的催化活性和更好的热稳定性,在Zn/AlPO4(摩尔比)为0.4时,HDI收率可达64.78%。

Twelve different molar ratio of Zn/AlPO4 for zinc-incorporated berlinite （ZnAlPO4） cataly-sts were prepared by hydrothermal synthesis method. The catalysts were characterized by XRD and XPS analyses. Their catalytic property was investigated in the catalytic decomposition of dimethylhex- ane-1,6-dicarbamate（HDC）, which were carried out on the stable and efficient reactor for cracking in the liquid phase self-designed. It was shown that ZnAlPO4 catalyst gave the better catalytic perform- ance when the molar ratio of Zn/AlPO4 was 0.4. The reaction conditions over ZnAlPO4 catalyst are as follows, dioctyl phthalate（DOP） as heat carrier, dimethyl phthalate（DMP） as solvent, reaction tem- perature of 523 K, reaction vacuum of 0.09 MPa, nitrogen flow rate of 100 mL/min, the feed rate of 10.00 g/（g . h）, molar ratio of ZnAlPO4/HDC 1.0%. The optimal conversion of HDC and the yield of HDI are 100% and 64.78%, respectively.