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℃, CO2partial 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 CO2adsorbent 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 CO2adsorbent 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%.%对包覆改性纳米CaO基CO2吸附剂的反应吸附性能进行研究,分别采用惰性材料MgO和TiO2对纳米CaCO3表面进行包覆改性,并以铝溶胶为黏结剂,通过混合造粒的方法制备改性纳米 CaO 基 CO2吸附剂.在相同的吸附温度(600℃)、CO2分压(0.015 MPa)、再生温度(750℃)以及N2气氛的条件下,采用热重分析仪(TGA)分别考察了吸附剂的分解温度、吸附速率、吸附容量及循环吸附容量的稳定性.结果表明:MgO和TiO2包覆改性吸附剂的分解温度较未包覆改性的吸附剂分解温度分别提高了20和35 ℃;经过30次循环后,包覆改性的吸附剂的吸附速率和吸附容量均明显大于未改性的吸附剂,其中包覆TiO2改性的吸附剂具有较好的吸附容量稳定性,30次循环后,吸附容量衰减率为34.85%,包覆MgO改性的吸附剂吸附容量衰减率为38.89%,而未经过包覆改性的吸附剂吸附容量衰减率为54.87%.
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