Carbonic anhydrase (CA) has a promising application as a green and efficient biocatalyst for CO 2 capture, and many successful cases of immobilizing CA have been reported. However, CA antifouling coatings on metal for CO 2 sequestration have rarely been reported. Herein, dimeric CA from Sulfurihydrogenibium azorense (SazCA) with a ferritin tag, which was prepared by low-speed centrifugation with high yield, was adopted as a free enzyme and encapsulated in the sol-gel silica . The silica-immobilized CAs were dispersed into the commercialized metal-antifouling epoxy resin paint to obtain CA coated nickel foams, which had excellent stability, with 90 % and 67 % residual activity after 28 days of incubation at 30 °C and 60 °C, respectively. The CA coated nickel foams remained 60 % original activity after 6 cycles of use within 28 days. Then, a CA-microalgae carbon capture device was constructed using the CA coated nickel foams and Chlorella . The growth rate of Chlorella was significantly increased and the biomass of Chlorella increased by 29 % compared with control after 7 days of incubation. Due to the simple and cost-effective preparation process, sustainable and efficient CO 2 absorption, this easy-to-scale up CA coated nickel foam has great potential in CA assisted microalgae-based CO 2 capture and carbon neutrality .
Yu Liu,Yu-Tong Li,Ling Liu,Shu Bai,Lin-Ling Yu,Yan Sun
Polyethylenimine (PEI)-grafted silica nanoparticles were fabricated and characterized for the electrostatic immobilization of a CO 2 conversion enzyme. PEI was supposed to serve as a carbonic anhydrase mimic for CO 2 capture and conversion to HCO 3 − (the optimal substrate of many CO 2 conversion enzymes) and was proved to assist phosphoenolpyruvate carboxylase to form a dual-enzyme cascade system for CO 2 conversion. The immobilized enzyme not only presented better thermostability, pH tolerance, and storage stability, but also enhanced the specific activity (three- and fourfold for HCO 3 − and CO 2 as the substrates, respectively), with good reusability and low cost. It was proven that PEI-grafted nanoparticles are highly efficient nanocarriers for immobilizing CO 2 -converting enzymes in industrial applications.
危险品化学品经营许可证（带存储）