Constructing the Al deficiency in Si-O(H)-Al units based on Pt/ZSM-5 for enhanced hydrocracking of polyethylene into high-quality liquid fuel  

作　　者：Xia Zhong Jie Liu Li Gao Junnan Chen Xiyang Wang Ying Zhang Yimin A. Wu Mozaffar Shakeri Xia Zhang Bingsen Zhang 

机构地区：[1]Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, 110016, China [2]School of Materials Science and Engineering, University of Science and Technology of China, Shenyang, 110016, China [3]Department of Chemistry, College of Science, Northeastern University, Shenyang, 110819, China [4]Department of Mechanical and Mechatronics Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada [5]School of Petrochemical Engineering, Liaoning Petrochemical University, Fushun, 113001, China [6]Laboratory of Heterogeneous Catalysis Department of Chemical and Petroleum Engineering, Chemistry and Chemical Engineering Research Center of Iran, Tehran, 16363, Iran

出　　处：《Nano Research》2024年第11期10088-10098,共11页纳米研究（英文版）

基　　金：the financial support provided by the National Natural Science Foundation of China(No.52161145403);the Iran National Science Foundation(No.4001399);the Research Fund of Shenyang National Laboratory for Materials Science.

摘　　要：Hydrocracking catalysis is a controllable route to plastic waste upgrading. However, the mismatched acid site-driven C-C cleavage and C=C hydrogenation process on metal restrict the efficiency and selectivity in conventional metal/acid bi-functional catalyst. Herein, we introduce Al deficiency in Si-O(H)-Al structural units of Pt/zeolite socony mobil-5 (Pt/ZSM-5) through discharge driven reduction (DR) process to precisely control the ratio of metal to acid, achieving hydrocracking of low-density polyethylene (LDPE) waste at 270 °C with 87.7% conversion and liquid fuel (C5-C21) selectivity of 77.8%. Pair distribution function (PDF) and nuclear magnetic resonance (NMR) spectroscopy demonstrate the partial absent Al sites further resulting short-range local disorder Si-O(H)-Al. Upon pyridine infrared spectroscopy (Py-IR) and CO diffuse reflectance Fourier-transform infrared (CO DRIFT) analysis, the extraction of Al modulates Brønsted acid density of Pt/ZSM-5 with DR process (Pt/Z5DR), improves the interaction between Pt and ZSM-5 support, enhances the cationic of Pt. The metal-acid balance and electron-deficient Pt favor the matching speed of light olefins hydrogenation and the cracking of macromolecule intermediates. Moreover, density functional theory (DFT) calculations identify the thermodynamic stability of Pt/Z5DR and moderate adsorption capability towards light olefins. This work confirms the great potential of precisely controlled molar of metal to acid in metal/zeolite catalysts for LDPE upcycling, providing a viable path for dealing with PE plastic wastes.

关 键 词：plastic upcycling HYDROCRACKING low-density polyethylene liquid fuel PT zeolites 

分 类 号：O64[理学—物理化学]