改性炭凝胶吸附低浓度二氧化碳及电解吸性能

Low-concentration CO2 capture by temperature and electric swing adsorption with modified carbon xerogel

针对密闭空间二氧化碳浓度低难捕集且吸附剂再生困难的现状,利用碳基材料良好的导电导热性能,采用电解吸工艺实现吸附剂的高效脱附,为碳基材料吸附低浓度CO2的研究提供理论依据。采用溶胶-凝胶法,在成胶过程中掺入金属合成金属-炭凝胶载体,再通过四乙烯五胺(TEPA)浸渍制备固态胺吸附剂,考察掺杂金属对CO2脱附的催化促进作用,同时探讨电解吸工艺的可行性。实验结果表明:脱附初始阶段,电脱附速率大于热脱附,且能更快达到最大脱附速率,因此电脱附具有快速高效的优势。且研究发现,相对于铜、锆等,掺铈材料吸/脱附速率快,吸/脱附量大,且电脱附能耗最少,具有一定的研究价值和意义。

Low-concentration CO2 in confined space is difficult to be captured by adsorbents and the regeneration capacity is low.In this study,carbonaceous materials with good electrical and thermal conductivity were developed as CO2 adsorbents for electric swing adsorption(ESA).Solid amine adsorbents were prepared by impregnating tetraethylenepentamine(TEPA)into metal-modified carbon xerogels,which were synthesized by a sol-gel method with dissolved metal ions.The effect of metal dopant on CO2 desorption was investigated and the ESA process was developed.It is demonstrated that adsorbents could be regenerated faster by direct heating with electricity than thermostat in the initial stage of the desorption process.In comparison with Cu and Zr-doped adsorbents,Ce-doped adsorbent is a promising CO2 adsorbent with faster adsorption/desorption rate,higher CO2 uptake and lower energy consumption.