C_4裂解制丙烯ZSM-5分子筛改性技术研究进展

Advances in modification of ZSM-5 zeolite for C_4 cracking to propylene

综述了国内、外对ZSM-5分子筛改性的主要方法。指出ZSM-5分子筛由于其特殊的三维孔道结构和孔径尺寸、稳定的骨架结构和大范围可调的硅铝比,具有优异的催化性能,可满足多种反应过程。镧改性可使反应体系以生成丙烯的反应为主,显著提高丙烯收率。磷改性ZSM-5能改善催化裂化催化剂的水热稳定性和活性。SiO2的修饰抑制了氢转移反应及液体产物中芳烃的生成。氟硅酸铵改性是一种疏通HZSM-5催化剂孔道和调节其酸性的有效方法。

Recent advances in modification of ZSM-5 zeolite were reviewed. ZSM-5 zeolite has excellent catalytic prpperties due to its special 3D pore path and radius size, stable skeletal structure and widely adjustable silica-alumina ratio. Modification of ZSM-5 zeolite with lanthanum enhances the selectivity. towards propylene. Doping of phosphorus improves the hydrothermal stability and activity of FCC catalysts. Modified with SiO2 inhibits the hydrogen transfer reactions and formation of aromatics in liquid product. Modification with （ NH4 ） 2SiF6 favors unclogging of the pore path and regulates its acidity.