近日，清华大学刘礼晨团队研究了沸石包封亚纳米Pt催化剂对高密度聚乙烯苯的选择性转化。相关论文于2026年3月16日发表在《美国化学会志》上。

将聚烯烃选择性转化为单一高附加值化学品可大幅提升升级回收工艺的技术经济性。然而，迄今为止大多数报道的催化过程只能将聚烯烃转化为混合烃类或含氧化合物。

研究组开发了一种择形催化路线，通过基于沸石限域亚纳米铂催化剂的两步法将高密度聚乙烯转化为苯：首先通过加氢裂化将高密度聚乙烯转化为混合烷烃，再通过脱氢芳构化将混合烷烃转化为苯。通过在β沸石内构建相邻的亚纳米铂簇与酸性位点，研究组可在极低铂负载量（约百万分之三百）下实现高密度聚乙烯加氢裂化的最高比活性，并获得高选择性液体烷烃。进一步地，由亚纳米双金属铂锡簇限域于MFI沸石构成的铂锡@MFI催化剂，可将液体烷烃选择性转化为苯，产率约45%。

附：英文原文

Title: Shape-Selective Conversion of High-Density Polyethylene into Benzene with Zeolite-Encapsulated Subnanometer Pt Catalysts

Author: Yunchao Feng, Hongtao Wang, Tianxiang Chen, Minghao Gao, Zhe He, Gaoqian Yuan, Lichen Liu

Issue&Volume: March 16, 2026

Abstract: Selective conversion of polyolefins into a single value-added chemical can greatly improve the techno-economy of the upcycling process. However, to date, most reported catalytic processes can convert polyolefins into only mixed hydrocarbon or oxygenate compounds. Herein, we have developed a shape-selective catalytic route for converting high-density polyethylene (HDPE) into benzene through a two-step process based on zeolite-confined subnanometer Pt catalysts, including the conversion of HDPE to mixed alkanes through hydrocracking and the subsequent conversion of mixed alkanes to benzene through dehydroaromatization. By constructing neighboring subnanometer Pt clusters and acid sites within β-zeolite, we can achieve the highest specific activity in the hydrocracking of HDPE at a very low Pt loading (～300 ppm) and high selectivity to liquid alkanes. Furthermore, the liquid alkanes are selectively converted into benzene with ～45% yield by a PtSn@MFI catalyst in which subnanometer bimetallic PtSn clusters are confined in the MFI zeolite.

DOI: 10.1021/jacs.5c14646

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c14646