“拟原位”法测定积炭催化剂有效扩散系数

"PSEUDO-IN SITU" METHOD FOR MEASURING EFFECTIVE DIFFUSIVITY OF COKED CATALYSTS

用新设计的单片反应器制备积炭催化剂试样,与动态法测定催化剂微孔有效扩散系数的装置相配合,并采用以水为吸附介质的动态毛细凝聚法和毛细上升法测定积炭催化剂压片的孔隙率,实现了积炭催化剂粒内有效扩散系数的“拟原位”测定要求,避免了催化剂颗粒反应积炭后再研磨、压片对有效扩散系数测定带来的假象。本文利用提出的“拟原位”方法得到了ZSM-5沸石催化剂上乙苯/乙烯烷基化过程中反应-失活全过程的有效扩散系数变化曲线。

A method using "pseudo-in situ" single pellet reactor (SPR) technique has been developed for measuring effective diffusivities of coked catalysts. This method eliminates the falsities caused by inadvisable sample preparation. To obtain the coked catalyst pellet sample, the catalyst powders were moulded into a sample-ring under 20 MPa in advance and a special designed single pellet reactor was used for reacting and coking. Then the coked catalyst sample ring was mounted in the diffusion cell apparatus direct...