The deposit is located in pores and channels of the crystal instead of on the surface. The coke on BPA-99H, new catalyst for trans-alkylation was also investigated.

• BPA-99H催化剂上的积炭主要是沉积在沸石孔道内的多烷基苯和萘，此类积炭若进一步发生氢转移、缩合、芳构化生成稠环芳烃则会造成催化剂失活。