Kinetics and mechanism analysis of CO2 adsorption on LiX@ZIF-8 with core shell structure

[email protected] is a kind of core-shell nanomaterial with high CO2 adsorption capacity applied to CO2 capture in highly humid flue gas. CO2/N2 separation performance and adsorption kinetics are another two critical indicators for a new adsorbent. Except for significant CO2/N2 separation capacity. The breakthrough curves of [email protected] under different adsorption temperatures were investigated by three kinetic models, namely pseudo-first order, pseudo-second order, and Avrami's kinetic model. It is proved that the pseudo-first order could successfully predict the adsorption behavior of [email protected] The normalized standard deviation of pseudo- first order model is only 2.8% at 25 °C. Furthermore, Boyd's film-diffusion model, interparticle diffusion model, and intraparticle diffusion model are selected to explore the mass transfer resistance of [email protected] It is found that film diffusion controls the adsorption rate in the initial stage and intense intraparticle diffusion is the rate-limiting reason in subsequent adsorption stage due to abundant micropores in LiX and ZIF-8.