title: The effect of positioning cations on acidity and stability of the framework structure of Y zeolite.
abstract: The investigation on the modification of NaY zeolite on LaHY and AEHY (AE refers Ca and Sr and the molar ratio of Ca and Sr is 1:1) zeolites was proformed by XRD, N2-physisorption (BET), XRF, XPS, NH3-TPD, Py-IR, hydrothermal stability, and catalytic cracking test. These results indicate that HY zeolite with ultra low content Na can be obtained from NaY zeolite through four exchange four calcination method. The positioning capability of La(3+) in sodalite cage is much better than that of AE(2+) and about 12 La(3+) can be well coordinated in sodalite cages of one unit cell of Y zeolite. Appropriate acid amount and strength favor the formation of propylene and La(3+) is more suitable for the catalytic cracking of cyclohexane than that of AE(2+). Our results not only elaborate the variation of the strong and weak acid sites as well as the Brönsted and Lewis acid sites with the change of exchanged ion content but also explore the influence of hydrothermal aging of LaHY and AEHY zeolites and find the optimum ion exchange content for the most reserved acid sites. At last, the coordination state and stabilization of ion exchanged Y zeolites were discussed in detail.
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.forename: Changshun
authors.initials: C
authors.lastname: Deng
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petro-Chemical Technology, Beijing 102617, P.R. China.
authors.forename: Junji
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.forename: Lihui
authors.initials: L
authors.lastname: Dong
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.forename: Meina
authors.initials: M
authors.lastname: Huang
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.lastname: Bin Li
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petro-Chemical Technology, Beijing 102617, P.R. China.
authors.forename: Guangzhou
authors.initials: G
authors.lastname: Jin
authors.affiliation: Department of Chemical Engineering, Beijing Institute of Petro-Chemical Technology, Beijing 102617, P.R. China.
authors.forename: Junbin
authors.initials: J
authors.lastname: Gao
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.forename: Feiyue
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Guangxi Key Laboratory Petrochemical Rescource Processing and Process Intensification Technology, School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, P.R. China.
authors.forename: Minguang
authors.initials: M
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Heavy Oil Processing, The Key Laboratory of Catalysis of CNPC, China University of Petroleum-Beijing, Beijing 102249, P.R. China.
authors.forename: Luoming
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Heavy Oil Processing, The Key Laboratory of Catalysis of CNPC, China University of Petroleum-Beijing, Beijing 102249, P.R. China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Gong