Li, Lin; Luo, Hu; Shao, Zilong; Zhou, Haozhi; Lu, Junwen; Chen, Junjun; Huang, Chaojie; Zhang, Shunan; Liu, Xiaofang; Xia, Lin; Li, Jiong; Wang, Hui; Sun, Yuhan

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY

2023, 145, 1520-5126

Li, Lin; Luo, Hu; Shao, Zilong; Zhou, Haozhi; Lu, Junwen; Chen, Junjun; Huang, Chaojie; Zhang, Shunan; Liu, Xiaofang; Xia, Lin; Li, Jiong; Wang, Hui; Sun, Yuhan

To solve the serious environmental problem and huge resource waste of plastic pollution, we report a tandem catalytic conversion of low-density polyethylene (LDPE) into naphtha, the key feedstock for renewable plastic production. Using beta zeolite and silicalite-1-encapsulated Pt nanoparticles (Pt@S-1), a naphtha yield of 89.5% is obtained with 96.8% selectivity of C5-C9 hydrocarbons at 250 degrees C. The acid sites crack long-chain LDPE into olefin intermediates, which diffuse within the channels of Pt@S-1 to encounter Pt nanoparticles. The hydrogenation over confined metal matches cracking steps by selectively shipping the olefins with right size, and the rapid diffusion boosts the formation of narrow-distributed alkanes. A conceptual upgrading indicates it is suitable for closing the plastic loop, with a significant energy saving of 15% and 30% reduced greenhouse gas emissions.