摘要
针对丙烯直接环氧化过程中原料气组成存在的问题,即大量稀释气以及O_2无法完全转化,通过计算无稀释气条件下O_2、 H_2和C_3H_6混合气体的爆炸限数据,得出O_2体积含量的安全范围(≤10%),移除了稀释气;通过考察了O_2体积含量及H_2/C_3H_6体积比对反应的影响,确定最优原料气组成为H_2/O_2/C_3H_6=62%/7%/31%,使O_2在反应过程中全部转化。并在此基础上研究了温度、压力和空速对反应的影响,探究了催化剂失活的原因。
Aiming at the problems existing in composition of feeding gas for the process of direct epoxidation of propene, namely, the big percentage of N_2 and incomplete conversion of O_2, by calculating the explosive limits of O_2, H_2 and C_3H_6, safety O_2 volumetric content(≤10%) has been found and the diluent gas has been removed. By investigating the influences exerted by O_2 content and H_2/C_3H_6 ratio on the process, the optimal composition of feeding gas has been acquired, i.e. H_2/O_2/C_3H_6=62%/7%/31%, so as to completely utilize O_2 during the process. The influences of reaction conditions and reasons that cause deactivation have also been investigated.
引文
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