CO_(2)-facilitated upcycling of polyolefin plastics to aromatics at low temperature  

作　　者：Yi Ding Shuchi Zhang Cheng Liu Yu Shao Xiulian Pan Xinhe Bao 

机构地区：[1]State Key Laboratory of Catalysis,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian 116023,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]Department of Chemical Physics,University of Science and Technology of China,Hefei 230026,China

出　　处：《National Science Review》2024年第5期229-236,共8页国家科学评论（英文版）

基　　金：supported by the National Natural Science Foundation of China(22321002).

摘　　要：Plastics are one of the most produced synthetic materials and largest commodities,used in numerous sectors of human life.To upcycle waste plastics into value-added chemicals is a global challenge.Despite significant progress in pyrolysis and hydrocracking,which mainly leads to the formation of pyrolysis oil,catalytic upcycling to value-added aromatics,including benzene,toluene and xylene(BTX),in one step,is still limited by high reaction temperatures(>500℃)and a low yield.We report herein CO_(2)-facilitated upcycling of polyolefins and their plastic products to aromatics below 300℃,enabled by a bifunctional Pt/MnO_(x)-ZSM-5 catalyst.ZSM-5 catalyzes cracking of polyolefins and aromatization,generating hydrogen at the same time,while Pt/MnO_(x) catalyzes the reaction of hydrogen with CO_(2),consequently driving the reaction towards aromatization.Isotope experiments reveal that 0.2 kg CO_(2) is consumed per 1.0 kg polyethylene and 90%of the consumed CO_(2) is incorporated into the aromatic products.Furthermore,this new process yields 0.63 kg aromatics(BTX accounting for 60%),comparing favorably with the conventional pyrolysis or hydrocracking processes,which produce only 0.33 kg aromatics.In this way,both plastic waste and the greenhouse gas CO_(2) are turned into carbon resources,providing a new strategy for combined waste plastics upcycling and carbon dioxide utilization.

关 键 词：POLYOLEFINS carbon dioxide AROMATICS upcycling bifunctional catalysis 

分 类 号：X705[环境科学与工程—环境工程]