In this work, the aqueous solutions of 1-hydroxyethyl-3-methylimidazolium lysine ([C₂OHmim][Lys]) and methyldiethanolamine (MDEA) were developed to obtain an efficient absorbent for CO₂ capture. The absorption performance, regeneration performance, reaction mechanism, and kinetic study of the blends were investigated. It was found that, for the blended absorbents, a molar ratio of 8:2 of MDEA/[C₂OHmim][Lys] was the optimum ratio based on the absorption rate, absorption capacity, and other factors. The CO₂ absorption capacity of the blends is 0.75 mol of CO₂/mol of ionic liquid, and the absorption rate was higher than that of the aqueous MDEA solution. The regeneration efficiency of the blends was 93% after the third absorption generation cycle, which was higher than the aqueous solutions of 1 mol/L MDEA (88%) or 1 mol/L [C₂OHmim][Lys] (88%) under the same conditions, indicating a better regeneration performance of the blends. The reaction mechanism and kinetic study of the CO₂ absorption into the blends were investigated by ¹³C nuclear magnetic resonance and a double stirred-cell absorber, respectively. [C₂OHmim][Lys] in aqueous solution first formed carbamate with CO₂, and the next step was hydrolysis of MDEA and partial carbamate, with the production of bicarbonate. It also found that the influence of the temperature in the CO₂ absorption was different in the two steps. Also, [C₂OHmim][Lys] could promote the hydration reaction of MDEA and CO₂ according to the chemical mechanism and kinetic study. The kinetic region was considered to be a fast pseudo-first-order reaction, and the activation energy of the blends was 40.0 kJ mol^–1.

中文翻译：

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二氧化碳吸收到甲基二乙醇胺/ 1-羟乙基-3-甲基咪唑赖氨酸/水体系中的机理和动力学研究

在这项工作中，开发了1-羟乙基-3-甲基咪唑赖氨酸（[C ₂ OHmim] [Lys]）和甲基二乙醇胺（MDEA）的水溶液，以获得有效的CO ₂捕集吸收剂。研究了共混物的吸收性能，再生性能，反应机理和动力学研究。已经发现，对于混合吸收剂，基于吸收速率，吸收容量和其他因素，MDEA / [C ₂ OHmim] [Lys]的摩尔比为8：2是最佳比例。共混物的CO ₂吸收能力为0.75 mol CO ₂离子液体的摩尔/摩尔比，并且吸收速率高于MDEA水溶液的吸收速率。在第三次吸收生成循环后，共混物的再生效率为93％，高于1 mol / L MDEA（88％）或1 mol / L [C ₂ OHmim] [Lys]（88％）的水溶液在相同条件下，表明共混物具有更好的再生性能。分别通过¹³ C核磁共振和双搅拌池吸收器研究了共混物中CO ₂吸收的反应机理和动力学研究。水溶液中的[C ₂ OHmim] [Lys]首先与CO ₂形成氨基甲酸酯，下一步是将MDEA和部分氨基甲酸酯水解，生成碳酸氢盐。还发现在两个步骤中温度对CO ₂吸收的影响是不同的。另外，根据化学机理和动力学研究，[C ₂ OHmim] [Lys]可以促进MDEA和CO ₂的水合反应。动力学区域被认为是快速的拟一级反应，共混物的活化能为40.0 kJ mol ^–1。