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论文类型：期刊论文

发表时间：2019-01-01

发表刊物：CATALYSIS SCIENCE & TECHNOLOGY

收录刊物：SCIE

卷号：9

期号：20

页面范围：5676-5685

摘要：Highly selective synthesis of renewable p-xylene (PX) from bio-based 2,5-dimethylfuran (DMF) and ethylene was successfully realized on H-Beta zeolite catalysts with further Al-modifications. The influences of different doping approaches on their reaction performances and coke deposition were systematically investigated. Solid-state NMR and SEM-EDS characterization indicates that the Al containing precursors have significant effects on the aluminum location and catalyst acidity. For H-Beta zeolite treated with aluminum nitrate, the contents of framework Al and Br?nsted acid sites increase obviously, causing the formation of more hard coke on the used catalyst as shown in13C CP/MAS NMR and TPO profiles, while for H-Beta zeolite modified with aluminum isopropoxide, more non-framework Al are formed in the pores of H-Beta, leading to severer soft and hard coke deposition. However, H-Beta zeolite after further doping with alumina shows excellent and durable performances with a PX yield of 97% at a 2,5-DMF conversion of ��100%. It also has good stability and regeneration capability. Most importantly, the coke content decreases from 12 to 7 wt% on the spent H-Beta-alumina catalyst with mainly soft carbonaceous species due to its appropriate Br?nsted/Lewis acid ratio. This work provides a deeper understanding of the role of B/L ratio in the sustainable conversion of 2,5-DMF and ethylene to p-xylene, paving the way for the synthesis of bulky chemicals from biomass feedstocks. This journal is ? The Royal Society of Chemistry.