CO2在ZIF-8/乙二醇-2-甲基咪唑浆液中溶解能力理论分析

有效降低CO₂排量实现碳中和是当前研究热点之一。ZIF-8/乙二醇-2-甲基咪唑浆液被发现不仅能高效地捕集CO₂，同时能利用浆液良好的流动性实现一个碳捕集-浆液流动再生-浆液再利用的连续碳捕集过程。为了有效地掌握纯CO₂气体在ZIF-8/乙二醇-2-甲基咪唑浆液中的溶解能力，本文首先测定了293.15K、303.15K和313.15K下CO₂在干ZIF-8上的吸附量和在2-甲基咪唑-乙二醇溶液中的溶解性；然后基于Langmuir方程和CO₂溶解机理进一步建立了相应吸附量和溶解度计算数学模型；最后综合考虑ZIF-8/乙二醇-2-甲基咪唑浆液中乙二醇和ZIF-8之间的共存特征和相互影响，建立了CO₂在目标浆液中溶解吸收量计算数学关联式。所得研究结果对浆液法CO₂技术的推广和后续流程模拟具有良好的指导作用和理论意义。

Theoretical analysis of CO2 dissolution ability in ZIF-8/glycol-2-methylimidazole slurry

Effectively reducing CO₂ emissions to achieve carbon neutrality is one of the current research hotspots. Our recent research found that ZIF-8/glycol-2-methylimidazole slurry can not only capture CO₂ from gas mixtures efficiently, but also make use of the good flow of the slurry, a continuous separation process of carbon capture-slurry regeneration-slurry reuse could be realized. In order to understand the solubility of pure CO₂ gas in ZIF-8/glycol-2-methylimidazole slurry, in this work, first, the adsorption ability of CO₂ in the dry ZIF-8 material and the solubility of it in the 2-methylimidazole-glycol solution at 293.15K, 303.15K and 313.15K and different pressures were measured. Meanwhile, based on the Langmuir equation and CO₂ dissolution mechanism in 2-methylimidazole-glycol solution, the corresponding CO₂ adsorption capacity and solubility calculation mathematical models were established. Finally, considering the coexistence characteristic and mutual influence of glycol and ZIF-8 in ZIF-8/glycol-2-methylimidazole slurry, a mathematical correlation equation for calculating the sorption amount of CO₂ in the target slurry was proposed. The obtained research results have good theoretical guidance for the promotion of CO₂ capture technology by using the ZIF-8 slurry and subsequent process simulation.