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Abstract：
Deep eutectic solvents (DES) are a generation of ionic liquids that benefit from low cost, good stability, and environmental-friendly features. In this research, a porous silica gel was impregnated with a eutectic Choline Chloride-Monoethanolamine solvent (ChCl-MEA) to greatly improve its CO2 capture performance. In the impregnation, the weight percentages of ChCl-MEA were used in the range of 10-60 wt% at a temperature of 25 °C. The effect of ChCl-MEA loading on the structural properties of the DES-modified silica samples was studied by BET, FTIR, and TGA analyses. Investigation of the CO2 adsorption performance at different operational conditions showed that the modified silica gel with 50 wt% ChCl-MEA (Silica-CM50) presents the highest CO2 capture capacity of 89.32 mg/g. In the kinetic modeling, the fractional order model with a correlation coefficient of 0.998 resulted in the best fit with the experimental data. In addition, the isotherm data for Silica-CM50 were well-fitted with the Dual site Langmuir isotherm model with a correlation coefficient of 0.999, representing two distinct sites for the adsorption process. Moreover, the thermodynamic parameters including Enthalpy, Entropy, and Gibbs free energy at 25 °C were obtained to be - 2.770, - 0.005 and - 1.162, respectively. The results showed the exothermic, spontaneous and feasibility of the adsorption process.
摘要：
低共熔溶剂（DES）是一种得益于低成本的离子液体，稳定性好,和环保的特点。在这项研究中,用低共熔氯化胆碱-单乙醇胺溶剂（ChCl-MEA）浸渍多孔硅胶，以大大提高其CO2捕集性能。在浸渍中，在25°C的温度下，ChCl-MEA的重量百分比在10-60重量%的范围内使用。通过BET研究了ChCl-MEA负载对DES改性二氧化硅样品结构性能的影响，FTIR,和TGA分析。在不同操作条件下对CO2吸附性能的研究表明，具有50wt％ChCl-MEA（Silica-CM50）的改性硅胶具有最高的CO2捕集能力，为89.32mg/g。在动力学建模中，相关系数为0.998的分数阶模型与实验数据拟合最佳。此外,Silica-CM50的等温线数据与双位点Langmuir等温线模型拟合良好，相关系数为0.999，代表吸附过程的两个不同位点。此外，热力学参数包括焓，熵,和吉布斯在25°C下的自由能分别为-2.770、-0.005和-1.162。结果显示放热，吸附过程的自发性和可行性。
