高选择性CO₂吸附剂的制备及评测

Investigation of High Selectivity Adsorbent for Carbon Capture

摘要: 碳捕集是工业生产和环境保护领域中至关重要的课题，高选择性CO₂吸附剂是目前该领域的热点研究方向之一。本文基于位阻效应机理，使用离子交换法对4A沸石分子筛进行改性，制备了不同K⁺交换率沸石分子筛样品，并针对CO₂-N₂体系进行吸附平衡和吸附动力学测试。研究结果表明，K⁺交换率对吸附性能有重要的影响，K⁺的增加会显著降低N₂的吸附量并使分子筛具有了择形吸附的功能，其中14.7%交换率的改性分子筛具有600左右的高选择性以及较快的吸附速率，具备了很好的应用前景。

Abstract: Carbon capture has always been widely concerned in regard to environmental protection and in-dustrial manufacturing. The carbon capture materials with high CO₂ selectivity and adsorbing ca-pacity become one of the urgent problems to be solved at present. On the basis of the steric effect, the ion exchange method was adopted to modify the zeolite 4A with K⁺ to achieve high selectivity adsorbents. The adsorption equilibrium data and the adsorption kinetic data of CO₂/N₂ were measured using the static adsorbing tests. The experimental and analytical results demonstrate that the exchange rate has important influence on the adsorption properties. The capacity of N₂ on various zeolites would decrease greatly with higher exchange rate. The adsorbent with 14.7% ex-change rate has good performance for adsorption selectivity and kinetics, with the selectivity about 600. It may be fundamental for applications of carbon capture by adsorption.