Synergistic dual-path electrosynthesis of sodium 2,2,3,3-tetrafluoropropionate enabled by microporous confinement in electrocatalytic membrane reactor

Sodium 2,2,3,3-tetrafluoropropionate (STFP) is a key fluorochemical, but conventional synthesis faces harsh conditions and pollution. Herein, an electrochemical membrane reactor (ECMR) was developed for the green synthesis of STFP. MnO x /Ti membrane anodes with varying MnO x loadings were prepared via ultrasonic-assisted impregnation-pyrolysis. In the ECMR (MnO x /Ti anode, stainless-steel mesh cathode), a mixed aqueous solution of 2,2,3,3-tetrafluoro-1-propanol (TFP) and NaOH was oxidized to yield STFP permeate. Electron spin resonance and radical quenching elucidated the mechanism. Under the optimized conditions, the 6.58 wt% MnO x /Ti electrode exhibited optimal activity due to uniform MnO x dispersion, achieving 34.68 % TFP conversion and 94.02 % STFP selectivity. Efficient synthesis is attributed to a synergistic mechanism: direct electron transfer mediated by Mn(IV) and anodic hole-induced •OH radical generation. Specifically, the three-dimensional porous structure of the MnO x /Ti membrane electrode enhanced mass transfer and promoted the contact between TFP and •OH/Mn(IV) active sites, finally accelerating product efflux, thereby improving reaction efficiency and selectivity. Purification of ECMR permeate yielded STFP with 90.27 % purity. This work provides a green strategy for sustainable fluorochemical synthesis.