Indirect H2O2 synthesis without H2
Arthur G. Fink, Roxanna S. Delima, Alexandra R. Rousseau, Camden Hunt, Natalie E. LeSage, Aoxue Huang, Monika Stolar, Curtis P. Berlinguette
Abstract
Abstract Industrial hydrogen peroxide (H 2 O 2 ) is synthesized using carbon-intensive H 2 gas production and purification, anthraquinone hydrogenation, and anthrahydroquinone oxidation. Electrochemical hydrogenation (ECH) of anthraquinones offers a carbon-neutral alternative for generating H 2 O 2 using renewable electricity and water instead of H 2 gas. However, the H 2 O 2 formation rates associated with ECH are too low for commercialization. We report here that a membrane reactor enabled us to electrochemically hydrogenate anthraquinone (0.25 molar) with a current efficiency of 70% at current densities of 100 milliamperes per square centimeter. We also demonstrate continuous H 2 O 2 synthesis from the hydrogenated anthraquinones over the course of 48 h. This study presents a fast rate of electrochemically-driven anthraquinone hydrogenation (1.32 ± 0.14 millimoles per hour normalized per centimeter squared of geometric surface of electrode), and provides a pathway toward carbon-neutral H 2 O 2 synthesis.