Semi-clathrates are a class of inclusion compounds in which a part of guest molecule involves in the formation of cage structure along with water and the other remaining part of guest molecule occupies and stabilizes the gas hydrate structure. Semi-clathrate based carbon capture encages carbon dioxide in hydrate cages which is an energy-efficient and economical pathway for carbon dioxide capture. This study examines the kinetics of tetrabutyl ammonium flouride (TBAF) based carbon dioxide capture at near ambient temperatures and the impact of amino acids on hydrate formation have been examined. The promotion effect of three selected amino acids - L-methionine, L-tryptophan and L-leucine on TBAF mixed semi-clathrates has been documented in this work. Experiments were conducted with simulated flue gas mixture of 25.2% CO/74.8% N at 8 MPa pressure and temperatures of 293.2 K and 298.2 K. The morphology of hydrate growth and the composition of recovered CO gas are also presented. Results indicate that lower TBAF concentration (10–20 wt%) experiments showcase an improved CO selectivity of up to 70% in the hydrate phase and higher TBAF concentration improved the total amount of gas stored per mole of water with a maximum of about 10 mmol of gas/mol of water. The gas uptake was found to increase for higher concentrations (20 wt% and 33.7 wt%) of TBAF in the solution. The average gas uptake value increased from 2.43 mmol/mol (10 wt% TBAF) to 9.96 mmol/mol (33.7 wt% TBAF) during the hydrate formation at 298 K and 8 MPa. 20 wt% TBAF solution showed highest separation of CO in hydrate phase. L methionine, L-tryptophan and L-Leucine amino acids in concentration range of 0.1 wt% - 2 wt% were used with 10 wt% TBAF solution amongst which 2 wt% L-methionine provided the best promotion.

中文翻译：

---

研究氨基酸存在下燃烧后 CO2 捕获的半包合物形成动力学

半包合物是一类包合物，其中一部分客体分子与水一起形成笼形结构，另一部分客体分子占据并稳定天然气水合物结构。基于半笼形物的碳捕获将二氧化碳捕获在水合物笼中，这是一种节能且经济的二氧化碳捕获途径。本研究研究了在接近环境温度下基于四丁基氟化铵 (TBAF) 的二氧化碳捕获的动力学，并研究了氨基酸对水合物形成的影响。这项工作已经记录了三种选定的氨基酸——L-蛋氨酸、L-色氨酸和L-亮氨酸对TBAF混合半笼形物的促进作用。实验采用 25.2% CO/74.8% N 的模拟烟气混合物在 8 MPa 压力和 293.2 K 和 298.2 K 温度下进行。还给出了水合物生长的形态和回收的 CO 气体的组成。结果表明，较低的 TBAF 浓度 (10–20 wt%) 实验表明，水合物相中的 CO 选择性提高了高达 70%，而较高的 TBAF 浓度则提高了每摩尔水储存的气体总量，最多约为 10 mmol气体/摩尔水。发现溶液中 TBAF 浓度较高（20 wt% 和 33.7 wt%）时，气体吸收量会增加。在298 K和8 MPa水合物形成过程中，平均气体吸收值从2.43 mmol/mol（10 wt% TBAF）增加到9.96 mmol/mol（33.7 wt% TBAF）。 20 wt% TBAF 溶液在水合物相中显示出最高的 CO 分离度。 L-蛋氨酸、L-色氨酸和L-亮氨酸氨基酸的浓度范围为0.1 wt% - 2 wt%，与10 wt% TBAF溶液一起使用，其中2 wt% L-蛋氨酸提供了最好的促进作用。