Dopamine-modified Highly Dispersed ZIF-8 to Promote CO2 Absorption

Graphical The modification of ZIF-8 with dopamine results in a large amount of hydrophilic and CO 2 friendly groups introducing into the ZIF-8 molecules, and the structure and specific surface area of ZIF-8 is also improved. These factors lead to an improvement performance of ZIF-8 in the catalytic CO 2 absorption in water and alkaline solutions. CO 2 capture technology has been widely used to reduce CO 2 emissions, resulting in a variety of capture methods and materials. Among them, the more widely used is the chemical absorption method. However, the chemical absorption method has problems such as high energy consumption and slow absorption rate. In order to solve the above problems, we prepared an effective catalyst to improve the CO 2 absorption rate. ZIF-8 and hydrophilic ZIF-8-DA were prepared by in situ synthesis under ambient conditions. The catalytic effect of the hydration reaction of ZIF-8 and ZIF-8-DA was tested using CO 2 absorption regeneration experiments under aqueous and alkaline conditions, respectively. The results showed that the synthesized catalysts could significantly enhance the CO 2 absorption in water and alkaline solution. The addition of 0.1 wt % of ZIF-8 in alkaline solution increased the average CO 2 absorption by 1.80–15.84 %, respectively, while the addition of 0.1 wt % of ZIF-8-DA increased the CO 2 absorption by 7.01–25.36 %. In addition, both catalysts had excellent reusability and maintained high performance even after five absorption and regeneration cycles. Polymer dispersibility index (PDI) results showed that ZIF-8-DA dispersed more uniformly in aqueous solution.