High Performance of Fly Ash Derived Li <sub>4</sub>SiO<sub>4</sub>-Based Sorbents for High Temperature CO<sub>2</sub>Capture

• 作者: Shenggen Wu Xiaoli Liang Qi Zhang Guiru Zhang
• 来源期刊: 封装与吸附期刊(英文)
• 学科: 化学
• 关键词: Fly Ash Lithium Orthosilicates Molar Ratios CO2 Capture
• 年，卷（期）: 2021,（1）
• 页码范围: 1-17
• 页数: 17页
• 分类号: O64

摘要

It is urgent to develop excellent solid CO₂ sorbents with higher sorption capacity, simpler synthetic process, better thermal stability and lower costs of synthesis in CO₂ capture and storage technologies. In this work, a number of Li₄SiO₄-based sorbents synthesized by lithium carbonate with three different kinds of fly ashes in various molar ratios were developed. The results indicate that the Li₂CO₃:SiO₂ mole ratio used in the sorbents synthesis significantly affects the CO₂ absorption properties. The sorption capacity increased with the excess of Li₂CO₃ first and then decreased when the excessive quantity was beyond a certain amount. The experiments found that FA-Li₄SiO₄_0.6, CFA-Li₄SiO₄_0.4, HCl/CFA-Li₄SiO₄_0.3 presented the best sorption ability among these fly ash derived Li_{<span style="font-family:Verdana;">4</span>}<span style="font-family:Verdana;">SiO</span>_{<span style="font-family:Verdana;">4</span>}<span style="font-family:Verdana;"> samples, and the corresponding weight gain was 28.2 wt%, 25.1 wt% and 32.5 wt%, respectively. The three sorbents with the optimal molar ratio were characterized using various morphological </span><span style="font-family:Verdana;">characterization techniques and evaluated by thermogravimetric analysis </span><span style="font-family:Verdana;">for their capacity to chemisorb CO₂ at 450</span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&deg</span></span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">C</span><span style="font-family:Verdana;"> - 650</span><span style="font-family:Verdana;"><span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;">&deg<