Tandem Electrocatalytic–Thermocatalytic Conversion of CO<sub>2</sub> to Aromatic Hydrocarbons
Samay Garg, Zhenhua Xie, Alexandria X. Lam, Jingguang G. Chen
Abstract
The reaction of CO 2 with H 2 O to produce aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene isomers) (BTEX) represents a promising pathway for converting CO 2 to value-added liquid products. However, this reaction cannot be achieved in a single electrochemical or thermochemical process. This work utilizes tandem electrochemical–thermochemical reactors as a new paradigm by starting with CO 2 and H 2 O as the feed in a membrane electrode assembly (MEA) to produce C 2 H 4, which subsequently undergoes thermochemical aromatization using a gallium- and phosphorus-modified zeolite ZSM-5 catalyst (Ga/ZSM-5/P) at ambient pressure to produce BTEX. The current study also demonstrates the potential advantage of the tandem strategy in mitigating negative effects of water by testing the tandem reactor system under different hydration conditions and by performing in situ X-ray diffraction (XRD) and X-ray absorption (XAS) characterization of the aromatization catalysts. These results highlight the advantage of using the tandem process with the use of a water trap before the thermochemical reactor.