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Updated: Jan 7, 2026
Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Ampere-level electroconversion of acetylene towards polymer grade ethylene via Pd-H mediated non-spillover
Lei Bai1, Xiao Han2, Dingding Li1
1International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics and Photon-Technology, Northwest University, Xi'an, Shaanxi, China.
Abstract:
Electroconversion of acetylene towards polymer-grade ethylene (EAE) is recognized as a promising substitution for thermo-catalytic route. The excessive active-hydrogen supplies a high current density induces the conspicuous hydrogen evolution, reducing the ethylene Faradaic efficiency (FE). Here, we develop a Cu-Pd single atom alloy (SAA) catalyst, achieving a 90.5% FE with a large ethylene partial current density of -1.16 A cm-2, and maintain stability for 110 h at -0.2 A cm-2 in the flow-cell system. In membrane electrode assembly, Cu-Pd SAA delivers a 90.1% ethylene FE and ~100 % conversion at -2.5 A (-0.1 A cm-2), along with 500 h stability for crude ethylene purification. Combined in-situ spectroscopy and DFT calculation reveal that the catalyst facilitates the direct hydrogenation of acetylene via Pd-H species rather than hydrogen spillover. This mechanism concurrently lowers the EAE energy barrier and suppresses the hydrogen evolution reaction. This work provides insights for designing high-efficiency electrocatalysts for hydrogenation electrosynthesis.
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