Plastic upgrading via catalytic pyrolysis with combined metal-modified gallium-based HZSM-5 and MCM-41  

作　　者：Huaping Lin Likai Zhu Ye Liu Vasilevich Sergey Vladimirovich Bilainu Oboirien Yefeng Zhou 

机构地区：[1]National&Local United Engineering Research Centre for Chemical Process Simulation and Intensification,College of Chemical Engineering,Xiangtan University,Xiangtan 411105,China [2]Institute of Power Engineering,National Academy of Sciences of Belarus,Minsk 220072,Belarus [3]Department of Chemical Engineering,University of Johannesburg,Johannesburg 17011,South Africa

出　　处：《Frontiers of Chemical Science and Engineering》2024年第11期179-191,共13页化学科学与工程前沿（英文版）

基　　金：National Natural Science Foundation of China(Grant No.22078278);Hunan Innovative Talent Project(Grant No.2022RC1111);Key Project of Hunan Provincial Education Department(Grant No.22A0131).

摘　　要：Currently,the conversion of waste plastics into high-value products via catalytic pyrolysis enables the advancement of plastics’open-loop recycling.However,enhancing selectivity remains a critical challenge.This study introduces a novel approach to catalytic pyrolysis,utilizing a combination of MCM-41 and modified gallium-based HZSM-5 catalysts,to achieve exceptional selectivity for aromatic liquid-phase products from linear low-density polyethylene.Firstly,to enhance the probability of dehydroaromatization optimization,the type and proportion of metal active sites within the HZSM-5 catalyst are fine-tuned,which would establish equilibrium with acid sites,resulting in a remarkable 15.72%increase in the selectivity of aromatic hydrocarbons.Secondly,to enhance the accessibility of volatiles to active sites,mesoporous MCM-41 with cracking capabilities is introduced.The doping ratio of MCM-41 is meticulously controlled to facilitate the diffusion of cracked volatiles to the active centers of modified gallium-based HZSM-5,enabling efficient reforming reactions.Experimental findings demonstrate that MCM-41 significantly enhances the dehydroaromatization activity of the modified gallium-based HZSM-5 catalyst.Under the influence of MCM-41:Zr_(2)Ga_(3)/HZSM-5=1:2 catalyst,the selectivity for aromatic hydrocarbons reaches an impressive 93.11%,with a notable 60.01%selectivity for benzene,toluene,ethylbenzene,and xylene.Lastly,this study proposes a plausible pathway for the generation of high-value aromatic hydrocarbons using the combined catalyst.

关 键 词：polyethylene pyrolysis aromatic hydrocarbons bimetal catalyst HZSM-5 MCM-41 

分 类 号：TQ426[化学工程] X705[环境科学与工程—环境工程]