在小型气固反应系统中,考察了不同反应条件下轻烃裂解催化剂H0108与1-P-H0108的反应性能,发现通水条件下有助于提高乙烯、丙烯收率,防止催化剂表面结焦,但对催化剂的结构稳定性有影响,尤其是催化剂H0108稳定性较差.对失活后的催化剂进行TG/DTG表征,结果表明,无水条件下两种催化剂表面均存在两种类型积炭,经750℃空气烧炭再生后恢复活性,说明结焦是引起催化剂失活的主要原因;通水条件下,也存在结焦失活,但催化剂通过烧炭只能部分恢复活性;通过催化剂的NH3程序升温脱附(NH3-TPD)表征,表明通水条件下不可逆的结构性变化可能是催化剂活性只能部分再生的主要原因.
Catalytic performance of catalysts (H0108 and 1-P-H0108) for the catalytic cracking of light hy- drocarbon was investigated in a fixed-bed plug-flow reactor under different reaction conditions. The yield of ethylene and propylene was enhanced and the formation of coke was restrained with the existence of water during the catalytic cracking process of light hydrocarbon. However, the stability of the catalyst was strongly affected by the water steam. TG/DTG results showed that there were two types of coke on the surface of the catalyst. The deactivated catalysts were almost completely regenerated by eliminating the coke at 750 ℃. The coking is the main cause of deactivation during the catalytic cracking without water. The activity of catalysts, which were deactivated in the presence of water, was partly retrieved by eliminating coke. In addition to the coking, the cause of deactivation in the presence of water is mainly due to the irreversible structural change of catalysts according to the temperature-programmed desorption of ammonia (NH3-TPD) results.