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采用浸渍法、机械混合法和水热法制备了Mo/HZSM 5分子筛催化剂 ,考察了Mo含量和在线反应时间对丙烷芳构化反应的影响 ,并以IR ,XRD ,NH3 TPD和XPS等表征手段研究了Mo物种对HZSM 5分子筛结构和酸性的影响 .结果表明 ,水热法制备的催化剂丙烷芳构化活性最高 ,且具有较高的活性稳定性 ,在焙烧过程中Mo物种易在HZSM 5分子筛上分散 ,且比浸渍法更多地进入分子筛孔道内 ,并与分子筛产生强相互作用 ,使B酸中心减少 ,L酸中心增多 .而浸渍法制备的催化剂的芳构化性能比相应的水热法催化剂低 ,活性稳定性较差 ,经焙烧后在分子筛外部形成结晶 ,进入孔道内的数量较少 ,对分子筛酸性的影响也低于水热法催化剂
Mo / HZSM 5 zeolite catalysts were prepared by impregnation method, mechanical mixing method and hydrothermal method. The effects of Mo content and on-line reaction time on propane aromatization were investigated. The effects of IR, XRD, NH3 TPD and XPS were investigated. The effects of Mo species on the structure and acidity of HZSM 5 molecular sieve were investigated. The results showed that the catalyst prepared by hydrothermal method has the highest aromatization activity of propane, and has high activity stability. During the calcination process, , And more enter the molecular sieve pores than the impregnation method, and with the strong interaction between the molecular sieve, the B acid center decreased, L acid center increased.The impregnation method of the catalyst preparation of the aromatization performance than the corresponding hydrothermal The catalyst has low activity and poor stability. After calcination, it forms crystals on the outside of the molecular sieve, and the amount of the catalyst entering the pore is small. The influence on the acidity of the molecular sieve is also lower than that of the hydrothermal catalyst