Abstract: Nano-plate twin crystal HZSM-5 is crystallized by hydrothermal method,and the pore structure of ZSM-5 is modified by NaOH or TPAOH.The results show that microporous ZSM-5 gains the perforated mesoporous structure by NaOH treatment and the multi-cavity structure is obtained by TPAOH treatment.The cavity connects to the outside through the micropore.ZSM-5 with different pore structure is modified by Zn and then used in methanol to aromatic reaction.The structures of different samples are analyzed by XRD,SEM,TEM and Argon physical adsorption.NH3-TPD is used to determine the acidic properties of different samples.Zn states in different samples are analyzed by XPS.The results show that Zn/HZ-TPAOH catalyst with multi-cavity structure can significantly improve the selectivity of aromatics,and the catalyst lifetime lengthens significantly.The lifetime of Zn/HZ-NaOH with connected mesoporous structure is significantly longer than that of Zn/HZ-TPAOH with multi-cavity structure.
李政杭, 刘民, 李俊杰, 郭新闻. 碱处理调控ZSM-5孔结构及其在甲醇制芳烃中的性能研究[J]. 现代化工, 2019, 39(11): 67-72.
LI Zheng-hang, LIU Min, LI Jun-jie, GUO Xin-wen. Modification of ZSM-5 by alkali treatment and its performance in methanol to aromatics. Modern Chemical Industry, 2019, 39(11): 67-72.
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