Functionalized hydrogel for efficient CO2 capture and biorefinery to produce volatile fatty acids

CO 2 capture and storage (CCS) is an effective way to solve the problem of high CO 2 emissions caused by large-scale use of fossil energy. Conventional CCS processes usually employ ethanolamine to store and produces toxicants during high-temperature regeneration. Here a functionalized hydrogel (FMI) consisting of Pluronic F127 by crosslinking imidazolidinyl urea (IU) was prepared. The incorporation of IU enhanced the FMI affinity for CO 2 by introducing a considerable number of N H bonds. The formation of hydrogen bonds facilitated the sequestration of CO 2 and improved the stability and plasticization resistance of the FMI. Meanwhile, a production blueprint was presented for converting captured CO 2 to volatile fatty acids (VFAs) by microbial refining. The addition of Pt/Fe 2 O 3 into biorefinery promoted the metabolic process of microorganisms by providing electron donors and acceptors. The carbon utilization was up to 97.27% and the concentration of produced VFAs was 33.98 g/L. Metagenomics further illuminated the microbial mechanism and confirmed feasibility of utilizing CO 2 to produce VFAs. The integration of hydrogel CO 2 capture technique with the biorefinery process improved the utilization of industrial waste gases and efficiency of biomass conversion. This study provides a non-toxic and environmentally friendly process in industrial waste gas separation and high value utilization.