Extremely low-volatility functional deep eutectic solvents (DESs), based on ethylene glycol (EG) and diethylene glycol (DG) as hydrogen-bond donor and the ammonium salts obtained from triethylenetetramine (TETA) and HCl at different mole ratios as hydrogen-bond acceptor, were designed and used to capture CO₂. All of the designed DESs can efficiently capture CO₂ even at low partial pressures. CO₂ absorption capacity of [TETA]Cl-EG DES with n_[TETA]Cl/n_EG 1:3 is high up to 17.5 wt % (1.456 mol CO₂/mol [TETA]Cl) at 40 °C and 1 atm. CO₂ absorption capacity decreases with increasing temperature and decreasing CO₂ partial pressure. Regeneration experiments show that CO₂ absorption capacities in [TETA]Cl-EG DES and [TETA]Cl-DG DES do not vary after five absorption/desorption cycles. It is found that EG or DG can increase the absorption capacity via activating −NH– or −NH₂ on [TETA]Cl and enhance the basicity of DESs. In addition, CO₂ absorption mechanism in [TETA]Cl-EG DES based on the change of its viscosity during absorption and FTIR analysis indicates that there is a chemical interaction between CO₂ and [TETA]Cl, and the stoichiometry for the reversible absorption is 1.5 molecules of CO₂ per [TETA]Cl-EG DES molecule.

中文翻译：

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功能性深共晶溶剂对CO ₂的高效可逆吸收

基于乙二醇（EG）和二甘醇（DG）作为氢键供体的极低挥发性功能性深共熔溶剂（DESs），以及以不同摩尔比从三亚乙基四胺（TETA）和HCl获得的铵盐作为氢键设计受体并捕获CO ₂。即使在较低的分压下，所有设计的DES都可以有效捕获CO ₂。n _TEACl / n _EG 1：3的[TETA] Cl-EG DES的CO ₂吸收能力在40°C和1个大气压下高达17.5 wt％（1.456 mol CO ₂ / mol TETACl）。 。CO _2的吸收能力随温度的升高和CO _2的降低而降低分压。再生实验表明，在5个吸收/解吸循环后，TECl-EG-DES和TECl-DG DES中的CO ₂吸收能力没有变化。发现EG或DG可通过活化TETACl上的-NH-或-NH ₂来增加吸收能力并增强DES的碱性。另外，基于TECl-EG DES在吸收过程中的粘度变化和FTIR分析，其CO ₂吸收机理表明CO ₂和TECl之间存在化学相互作用，并且化学计量可逆吸收每个[TETA] -C1-EG DES分子中有1.5个CO ₂分子。