吸热燃料在管式涂层反应器内的催化裂解反应

Catalytic Cracking of Endothermic Fuels in Coated Tube Reactor

采用气体辅助催化剂涂层技术将一种陶瓷类黏合剂与HZSM-5和HY分子筛混和涂敷在管式反应器内壁,并采用X射线衍射,傅里叶变换红外光谱和扫描电子显微镜对催化剂涂层进行了表征。表征结果显示,催化剂涂层的厚度为10～20μm,催化剂的粒径为1～5μm。以正十二烷和航空燃料RP-3为吸热燃料,在600℃和625℃的超临界条件下考察了催化剂涂层对吸热燃料的热沉和裂解率的影响。实验结果表明,催化剂涂层能显著提高吸热燃料的热沉。在600℃和625℃下,使用HY催化剂涂层(质量分数25%)时,正十二烷的热沉分别比空管反应时增加815.7kJ/kg和901.9kJ/kg,同时裂解率也分别由空管反应时的42%和66%提高到60%和80%。催化剂涂层对吸热燃料催化裂解积碳也有一定的抑制作用。

Suspensoid of HZSM-5 or HY zeolites mixed with a self- made ceramic- like binder was coated on inner wall of a tubular reactor by gas - aided fluid displacement technology. Coated zeolites were characterized by means of XRD, FFIR and SEM. Coating thickness is 10 -20 μm and particle size of zeolites is in range of 1 - 5 μm. Simulative cracking of n - dodecane and aviation fuel RP - 3 was carried out separately under supercritical conditions at 600 ℃ and 625 ℃ to investigate their heat sink and conversion. When coating layer contained HY zeolite （25 % mass fraction）, heat sinks of n- dodecane are 815. 7 kJ/kg and 901. 9 kJ/kg higher than that of bare tube respectively at corresponding temperatures. Conversion of n -dodecane increases from 42% to 60% at 600℃ and 66% to 80% at 625℃. The coated zeolite could inhibit carbon deposition on inner wall of reactor.