研究了纳米CaO含量对CO2吸附剂微观结构和吸附性能的影响。以纳米CaCO3和铝溶胶为前驱体配制混合浆料,采用挤条方法制备CaO含量为6%~100%的CO2吸附剂颗粒,微观结构性能测试结果表明:CaO含量从6%提高到46%,比表面积从151.3 m2.g.1下降到8.1 m2.g.1,孔容从0.41 cm3.g.1下降到0.07 cm3.g.1,孔径从6.05 nm提高到12.39 nm。提高到CaO含量46%以上,吸附剂比表面积和孔结构没有变化,接近纯纳米CaO。当CaO含量超过27%后,氧化铝呈非晶形。吸附性能测试结果表明:随着CaO含量从12%提高到83%,吸附容量从1.02 mol CO2.kg.1增加到7.05 mol CO2.kg.1,吸附速率提高。研究结果还表明:CaO含量对纳米CaO基CO2吸附剂的微观结构和吸附性能的影响呈非线性关系。与纯CaO相比,加入少量氧化铝能提高吸附剂对CO2的吸附容量稳定性和吸附速率。
The CO2 adsorbents with CaO contents of 6% to 100% were prepared by mixing the nano CaCO3 power with the alumina gel,and the effects of nano CaO content on the adsorption and microstructure properties of the CO2 adsorbent were studied.The results of microstructure property examinations show that,when the nano CaO content of CO2 adsorbent increases from 6% to 46%,the specific area decreases from 151.3 m^2·g·^-1 to 8.1 m^2·g·^-1,and the pore volume decreases from 0.41 cm^3·g^-1 to 0.07 cm^3·g^-1.However,when nano CaO content of CO2 adsorbent increases 27% to 46%,the pore size increases from 6.05 nm to 12.39 nm,and when CaO content is over 46%,the specific area and pore structure of the CaO adsorbents are similar to those of the pure CaO.The alumina in the adsorbent is amorphous when the CaO content is more than 27%,and the results of adsorption property experiments show that the adsorption capacity of nano CaO adsorbent increases from 1.02 mol CO2·g·^-1 to 7.05 mol CO2·g·^-1/ when the CaO content increases from 12% to 83%.The adsorption rate becomes faster when CaO content of the CO2 adsorbent increases,and the results show that the relationship of CaO content to microstructure and adsorption properties of the nano CaO based adsorbents isn't linear.It was found that the stability of adsorption capacity and the adsorption rate of the CO2 adsorbent can be improved by adding a small amount of alumina.