改性HZSM-5分子筛催化剂芳构化性能研究

制备Ni改性及水热改性HZSM-5分子筛催化剂，并在固定床连续微型反应装置上考察对正辛烷芳构化反应的催化性能。采用低温氮吸附、NH₃-TPD和FT-IR等方法对催化剂进行表征。结果表明，随着Ni含量的增加，催化剂B酸逐渐减少，L酸逐渐增多，总酸呈现出先减少后增多的趋势，适宜的Ni含量能够促进芳构化反应。随着水热温度的提高，B酸减少，总酸增多，催化剂的芳构化活性逐渐降低。催化剂活性与表面酸性有关，尤其是与强酸量有关，强酸量下降，芳构化能力下降。

Study on aromatization performance of modified HZSM-5 zeolite catalyst

Zeolite ZSM-5 was modified by Ni and hydrothermal treatment. The catalytic properties of mod- ified HZSM-5 zeolite catalyst for aromatization of n-octane were investigated in the continuous fixed-bed micro-reactor. The as-prepared catalyst was characterized by N2 adsorption, NH3-TPD and FT-IR. The results showed that Brisnsted acid of the catalyst decreased, Lewis acid enhanced and the total acid firstly decreased and then increased with increase of nickel loading. Proper Ni could promote aromatization. With the increase of hydrothermal treatment temperature, Bronsted acid decreased and total acid increased, which resulted in the decrease of aromatization activity. The activity of the catalysts related to surface acidity and especially strong acid amount. Aromatization ability reduced with the decrease of strong acid amount.