劣质原油高效转化且增产低碳烯烃的择型分子筛研究进展

现有催化裂化多产低碳烯烃技术优先以石蜡基蜡油或常压渣油为原料油,原油重质化和高硫化限制了该技术的深入发展与推广应用。择型分子筛由于硅铝比及孔结构较为突出,具有适合重质油裂解的反应性能,得到广泛应用。为了更好的提高低碳烯烃的产率及选择性,对择型分子筛进行改性,通过调整分子筛的基础性质,使之成为优良的活性中心。重点介绍多种择型分子筛包括ZSM-5、β、SAPO-34、MCM-22等,并对其现有改性方法主要是以酸、碱改性及金属、非金属改性为主进行综述,并从其改性后的性能包括孔道结构优化、水热稳定性保留及裂化能力增强等方面阐述分子筛改性研究进展。

Research review on shape selective molecular sieves for efficient conversion of inferior crude oil and upgrading of light carbon olefins

The existing catalytic cracking for light carbon olefins was based on wax oil or normal pressure residue as raw material.More heavy crude oil greatly restricted development and application of this technology.Because of special pore structure and wide adjustable silicon and aluminum ratio,shape selective molecular sieves possessing excellent catalytic properties had been widely used.In order to increase selectivity and yield of the light olefin,modification of selective molecular sieves was studied.By adjusting number and intensity of zeolites acid site,catalytic activity could be improved.Various types of zeolites,including ZSM-5,Beta,SAPO-34 and MCM-22,were introduced in this paper.The main modification methods of zeolites were reviewed,including acid-base modification,metal and non-metal modification.The progress on properties after modification,including pore structure optimization,hydrothermal stability retention and cracking capacity enhancement were discussed.