Boosting Selective Oxidation of Ethylene to Ethylene Glycol Assisted by In situ Generated H₂O₂ from O₂ Electroreduction

Abstract

Ethylene glycol is a useful organic compound and chemical intermediate for manufacturing various commodity chemicals of industrial importance. Nevertheless, the production of ethylene glycol in a green and safe manner is still a long-standing challenge. Here, we established an integrated, efficient pathway for oxidizing ethylene into ethylene glycol. Mesoporous carbon catalyst produces H 2 O 2 , and titanium silicalite-1 catalyst would subsequently oxidize ethylene into ethylene glycol with the in situ generated H 2 O 2 . This tandem route presents a remarkable activity, i.e., 86 % H 2 O 2 conversion with 99 % ethylene glycol selectivity and 51.48 mmol g ecat À 1 h À 1 production rate at 0.4 V vs. reversible hydrogen electrode. Apart from generated H 2 O 2 as an oxidant, there exists * OOH intermediate which could omit the step of absorbing and dissociating H 2 O 2 over titanium silicalite-1, showing faster reaction kinetics compared to the ex situ one. This work not only provides a new idea for yielding ethylene glycol but also demonstrates the superior of in situ generated H 2 O 2 in tandem route.

The Nexus of Innovation: Electrochemically Synthesizing H2O2 and Its Integration with Downstream Reactions

“…This pathway involves a two-step tandem route that leverages the unique properties of two distinct catalysts (Figure 3a). 69 In the first step, a mesoporous carbon catalyst is employed to produce H 2 O 2 , and then a titanium silicalite-1 (TS-1) catalyst is utilized to oxidize ethylene into ethylene glycol using the in situ generated H 2 O 2 . The synergy between these two catalysts in the tandem route results in remarkable activity.…”