Zichun Wang, L. O’Dell, Xin Zeng
Oct 30, 2019
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0
Influential Citations
35
Citations
Journal
Angewandte Chemie
Abstract
Ethylene, a key chemical in the synthesis of plastics, fibres, rubbers, solvents and many other necessary chemicals , is produced from petroleum- and coal-based industrial chemical processes. Commercial bioethanol is a renewable low-cost feedstock that can be readily converted into ethylene by dehydration process using solid acids, such as Brønsted acidic H-ZSM-5 zeolites, and thus it is an ideal candidate to replace petroleum and coal for the sustainable production of ethylene. In this work, strong Lewis acidic extra-framework tri-coordinated Al 3+ species were introduced into H-ZSM-5 zeolites to improve their catalytic activity. Remarkably, Al 3+ species working with Brønsted acid sites can accelerate ethanol dehydration at the much lower reaction temperature and short unsteady-state period within 1~2 h, compared to > 9 h for those without Al 3+ species, which can significantly enhance the ethanol dehydration efficiency and reduce the cost. Reaction mechanism studied by solid-state NMR shows that strong Lewis acidic EFAl-Al 3+ species can collaborate with Brønsted acid sites and promote ethanol dehydration either directly or indirectly via an aromatics-based cycle to produce ethylene dehydration.