Adsorption Properties of Coating Modified Nano CaO-Based CO2 Adsorbents
1. College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China;
2. Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, China
Abstract The adsorbent was prepared in a spray granulation method by mixing the inert material MgO or TiO2 coating modified with nano-CaCO3 and with alumina sol as binder. The thermo-gravimetric analyzer was used to investigate the decomposition temperature, adsorption rate, adsorption capacity and stability under the conditions of reactive carbonation temperature 600 ℃, CO2 partial pressure 0.015 MPa，and calcination temperature 750 ℃ in nitrogen gas. The results showed that the decomposition temperature of MgO, TiO2 coating modified nano CaO-based CO2 adsorbent was increased by 20 and 35 ℃, respectively. The adsorption rate and adsorption capacity were both higher than those of uncoated nano CaO-based CO2 adsorbent after 30 carbonation-calcination cycles. The TiO2 coated nano CaO-based CO2 adsorbent had the highest stability with 34.85% decrement after 30 cycles, and the MgO coated one was 38.89% while the uncoated nano CaO-based CO2 adsorbent was 54.87%.
