Li4SiO4对CO2捕集性能的实验研究

以Li₂CO₃和SiO₂为原料,通过高温固相合成法合成了CO₂捕集剂Li₄SiO₄,并用X射线粉末衍射仪(XRD)、扫描电子显微镜(SEM)对所合成的材料在CO₂捕集前后的晶相变化以及微观结构进行了表征。通过热重分析仪(TGA)研究了Li₄SiO₄材料吸附CO₂的性能,并在小型热态实验台架上进行了CO₂热态捕集实验。实验结果表明,Li₄SiO₄对CO₂的捕集性能受Li₄SiO₄合成温度、CO₂的吸附温度以及气体中CO₂含量的影响,在700 ℃下制得的Li₄SiO₄具有最佳的CO₂吸附特性,最大吸附增量可达34%。Li₄SiO₄的吸附能力随着CO₂含量和吸附时间的增加而增加,当CO₂浓度分别为75%、67%、60%时,700 ℃ Li₄SiO₄对CO₂最大吸附量分别可达6.68 mmol/g、3.37 mmol/g、2.02 mmol/g (理论量8.33 mmol/g)。

Experimental study on Li4SiO4 adsorption capability for CO2 capture

Li4SiO4 used as a revolving CO2 absorbent at determinate temperature can be synthesized with SiO2 and Li2CO3 by solid state reaction at high temperature.The crystal structure and microstructure of Li4SiO4 were characterized by X-ray diffraction(XRD) and Scanning Electron Microscopy(SEM),respectively.The CO2-adsorption capability of Li4SiO4 was studied by TGA preliminarily,and then was tested in a small experimental apparatus.The results show that the CO2-adsorption capability is influenced by the preparation temperature of Li4SiO4 synthesis,and it was the largest at 700℃.The maximum adsorption capability could achieve 34%.Besides,the adsorption capability increases as the adsorption temperature going up and longer time.When CO2 concentration was 75%,67%,60%,the adsorption capability could respectively reach 6.68mmol/g,3.37mmol/g,2.02mmol/g.