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以乙二醇和乙醇为原料,采用硫酸铵改性的HZSM-5(MHZSM-5)作催化剂合成了乙二醇乙醚和乙二醇二乙醚,乙二醇的转化率高达69.1%,乙二醇乙醚和乙二醇二乙醚的选择性分别为72.9%和25.3%。结果表明,MHZSM-5具有良好的催化效果,但重复使用时催化剂的活性降低较快。采用X射线衍射仪(XRD),NH3-TPD,扫描电子显微镜(SEM),电子能谱(EDS),比表面积及孔径测定仪(BET法)和热重/差热分析仪(TG)对催化剂的晶型结构、表面形貌、酸度、元素变化、比表面及孔径进行了表征。结果表明,催化剂的失活主要是由催化剂表面积碳引起的孔道堵塞和表面S元素的流失造成,整个使用过程中催化剂的晶型结构未发生明显变化。
Ethylene glycol and ethylene glycol diethyl ether were synthesized from ethylene glycol and ethanol using HZSM-5 (MHZSM-5) modified by ammonium sulfate as catalyst. The conversion of ethylene glycol was as high as 69.1% The selectivity for diethyl ether and ethylene glycol diethyl ether was 72.9% and 25.3%, respectively. The results show that, MHZSM-5 has a good catalytic effect, but when reused catalyst activity decreased rapidly. The catalysts were characterized by X-ray diffraction (XRD), NH3-TPD, scanning electron microscopy (SEM), electron spectroscopy (EDS), BET surface area and pore size analyzer The crystal structure, surface morphology, acidity, elemental changes, specific surface area and pore size were characterized. The results show that the deactivation of the catalyst is mainly caused by the clogging of the pores and the loss of the surface S element caused by the surface carbon deposition on the catalyst surface. The crystal structure of the catalyst does not change obviously during the whole use.