Pickering interfacial biocatalysis with enhanced diffusion processes for CO2 mineralization

Utilization of carbon dioxide (CO 2 ) has become a crucial and anticipated solution to address environmental and ecological issues. Enzymes such as carbonic anhydrase (CA) can efficiently convert CO 2 into various platform chemicals under ambient conditions, which offers a promising way for CO 2 utilization. Herein, we constructed a Pickering interfacial biocatalytic system (PIBS) stabilized by CA-embedded MOFs (ZIF-8 and ZIF-L) for CO 2 mineralization. Through structure engineering of MOFs and incorporation of Pickering emulsion, the internal and external diffusion processes of CO 2 during the enzymatic mineralization were greatly intensified. When CO 2 was ventilated at a flow rate of 50 mL min –1 for 1 h, the pH value of PIBS dropped from ~8.00 to ~6.50, while the average pH value of free system only dropped to ~7.15, indicating that the initial reaction rate of CO 2 mineralization of PIBS is nearly twice that of the free system. After the 8 th cycle reaction, PIBS can still produce more than 9.8 mg of CaCO 3 in 5 min, realizing efficient and continuous mineralization of CO 2 . We developed a Pickering interfacial biocatalytic system (PIBS) stabilized by CA-embedded ZIFs which promotes CO 2 mineralization by fortifying internal and external diffusion processes.