The durability of methane dehydroaromatization (MDA) has been improved by its combination with methane steam reforming (MSR). The methane conversion in the combined MSR/MDA system decreases very slowly from 11.5% at 12.5 h to 6.5% at 60 h, whereas it decreases rapidly from 14.5% at 0.5 h to 3.5% at 15 h for the MDA reaction alone. CO and H_2 produced in-situ through the MSR reaction may reduce the amount of CH, species during the reaction, which in turn reduces the formation of coke deposited on the catalyst, prolonging the durability of the MDA reaction. High content of H_2 from the MSR process plays a major role in suppressing coke accumulation on the catalyst, especially the coke associated with the Bronsted acidic sites that are mainly responsible for the deactivation.%甲烷无氧芳构化(MDA)和甲烷水蒸气重整(MSR)的耦合反应可以大幅度提高甲烷无氧芳构化反应的稳定性.单独的甲烷无氧芳构化反应失活较快,甲烷转化率从0.5 h的14.5%很快下降至15 h的3.5%.而采用联合MSR/MDA反应体系,甲烷的转化率从12.5 h的11.5%非常缓慢地下降至60 h后的6.5%.MSR反应原位生成的CO和H_2能降低反应中生成的CHr物种数量,减少催化剂上积炭的牛成,进而延长反应时间.MSR反应过程中高比例H_2的生成更能有效地减少与B酸相关的积炭的生成,从而更好地抑制反应的失活.
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