Abstract: The Lithiumbased sorbents for high temperature CO₂ capture were prepared through solidstate reaction method and precipitation method, which were characterized by Xray diffraction(XRD) and scanning electronic microscopy(SEM). The CO₂ absorption performance was evaluated by the chemical BET absorption(CHEMBET) method and the impact factors (including synthetic method, calcination temperature, molar ratio of Li to Si and different silica sources) were studied. The results indicated that the particle size of the adsorbents synthesized by the precipitation method distributed more homogeneous than that of the adsorbents synthesized by the solidstate reaction method at 750 ℃. Meanwhile, BET surface area of former was larger than that of latter. After six times CO₂ (carbon dioxide to helium in a volume ratio of 1∶5) recycles, adsorption capacity of precipitationmethod adsorbents using SiO₂II reduced to 9.92% from 13.38%, and desorption amount decreased from 11.74% to 8.52%. However, the amounts of adsorption and desorption of precipitationmethod adsorbents using SiO₂I were reduced by 2.61% and 2.39%, those of solidstatemethod adsorbents reduced by 1.85% and 1.42%. 

Key words: Lithiumbased sorbent,    ,  Carbon dioxide,    ,  Solidstate reaction method,    ,  Precipitation method

摘要： 采用高温固相合成法和沉淀法分别制备了高温CO₂ 吸附剂正硅酸锂( L i 4S i O4) , 利用 X射线粉末衍射仪( XR D) 和扫描电镜( S EM) 对吸附剂进行表征, 化学吸附仪测试CO₂  吸附/脱附性能, 研究了合成方法、 焙烧温度、 锂硅物质的量比和不同硅源对吸附剂的影响。实验结果表明, 在7 5 0℃下沉淀法制备的吸附剂比固相法合成的颗粒分布均匀, 经过6次 CO2( VCO 2/ VH e=1∶5) 吸附 - 解吸循环后, 以S i O₂ - I I为硅源的沉淀法吸附剂吸附量由 1 3. 3 8%降为9. 9 2%, 解吸量由1 1. 7 4%降为8. 5 2%; 以S i O2 - I为硅源的沉淀法吸附剂的吸附量、 解吸量大约下降 2. 6 1%、 2. 3 9%, 固相法吸附剂的吸附量、 解吸量分别下降1. 8 5%、 1. 4 2%。

关键词: 正硅酸锂, 二氧化碳, 高温固相法, 沉淀法