十氢萘催化裂解制低碳烯烃研究进展

RESEARCH PROGRESS IN DEEP CATALYTIC CRACKING OF DECALIN TO LOW-CARBON OLEFINS

综述了十氢萘在不同类型催化剂作用下的裂解反应机理:十氢萘在金属氧化物催化剂上晶格氧和吸附氧物种作用下,经负碳离子转变为自由基,进而以自由基机理裂解;十氢萘在固体酸催化剂的B酸中心上形成正碳离子,接着以正碳离子机理进行反应。分析了不同类型裂解催化剂的优缺点:金属氧化物催化剂耐水热、耐高温且可抑制结焦,但对于大幅降低反应温度和提高丙烯产率无促进作用;固体酸催化剂因含有的酸中心和独特的孔道结构,可大幅降低反应活化能,且可灵活调变低碳烯烃比例。最后,列举了不同工艺条件对十氢萘裂解反应的影响。

The reaction mechanism of decalin under the action of different types of catalysts is reviewed.Decalin is converted to free radicals by carboanion and then cracked by free radical mechanism under the action of lattice oxygen and adsorbed oxygen species on metal oxide catalysts.Decalin forms carbocation on the B acid center of solid acid catalyst,and then it reacts with a carbocation mechanism.Advantages and disadvantages of different pyrolysis catalysts were analyzed.The metal oxide catalysts were resistant to hydrothermal and high temperature,and could inhibit coking,but had no promoting effect on greatly decreasing reaction temperature and increasing propylene yield.Solid acid catalyst has acid center and unique pore structure,which can greatly reduce the reaction activation energy and flexibly adjust the proportion of low carbon olefins.Finally,the effects of different process conditions on decalin cracking reaction were listed.