In situ capture and value-added utilization of CO2 from flue gas using an ionic liquid polymer supported Zn catalyst†

Abstract

In this work, a porous organic polymer supported Zn catalyst (Zn@PIP-1) complexed with an ionic liquid (IL), zinc halide (ZnX₂), and vinyl-functionalized triphenylphosphine (p-3vPPh₃) has been synthesized by a one-pot method and used for the capture and conversion of waste carbon dioxide (CO₂ 19.4%) from flue gases of complex composition into valuable cyclic carbonates. Combined structure characterization studies of Zn@PIP-1 revealed successful integration of multiple sites and excellent structural stability, conferring high activity and stability under mild, additive-free conditions. The catalyst showed good group tolerance and a series of carbonates with different structures were successfully obtained in high yields. In addition, the catalyst was recyclable and could be successively used 5 times without obvious activity loss. We systematically evaluated the catalyst's robustness through rigorous poisoning resistance assessments against major flue gas contaminants. The experimental data revealed exceptional tolerance thresholds: (1) sustained catalytic efficiency (99% yield retention) under extreme oxidative conditions (O₂, 53 333 ppm), (2) unimpaired performance at CO concentrations exceeding 33 333 ppm, and (3) 99% product yield maintained in the presence of 51 233 ppm H₂O. This work provides some insights into the design of stable polymer catalysts for efficient CO₂ transformation.