混合醇胺MEA/TEA水溶液吸收二氧化碳之反應動力學數據量測研究

The study of the reaction kinetics of CO2 with aqueous MEA/TEA solutions

洪世諭(Shyh-Yun Horng)

指導教授 ： 李夢輝

中原大學/工學院/化學工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100025

摘要

本研究主要為探討CO2與混合醇胺MEA/TEA水溶液的反應動力學，其濃度範圍
為MEA (0.1-0.5 kmol·m-3) / TEA (0.5 kmol·m-3)及MEA (0.1-0.5 kmol·m-3) / TEA (1.0 kmol·m-3)
，溫度是30、35及40°C。對於CO2，本研究以pseudo-first-order的模式來描述CO2與醇
胺之反應動力行為，而對於MEA、TEA則分別用兩性離子機構及一級反應的反應動
力學模式來探討。本實驗亦量測其相關物理性質：密度、黏度、亨利常數及擴散係
數等相關數據，以提供計算二氧化碳反應吸收的數學模式時所需的數據。

每種醇胺在使用上都有其個別的優缺點，因此近年來有學者提出使用摻合醇胺
的提議，以不同之組成比例來混合醇胺形成三成份的混合醇胺水溶液，目的在於結
合各醇胺之吸收特性，發揮其優點而彌補彼此的缺點。本實驗選用MEA/TEA/H2O系
統，取MEA對CO2有較高的吸收速率，及TEA對CO2有較高的吸收容量等優點來進
行實驗。

由實驗結果可發現，本研究的實驗範圍符合擬一級反應之條件的假設，且混合
兩性離子機構及一級反應可以用來合理解釋CO2與MEA、TEA的反應。而且我們可
以得知，在TEA醇胺水溶液中，加入少量的MEA，確實能使系統的反應吸收速率
提升。

關鍵字

混合醇胺MEA/TEA水溶液 ； 吸收

並列摘要

The reaction kinetics of the carbon dioxide with aqueous monoethanolamine (MEA) and
triethanolamine (TEA) solutions were studied at temperature ranging from 30 to 40°C. The
system studied were MEA (0.1 to 0.5 kmol·m-3) / TEA (0.5 kmol·m-3) and
MEA (0.1 to 0.5 kmol·m-3) / TEA (1.0 kmol·m-3). A hybrid kinetics model combining the
zwitterion mechanism and the first-order reaction was used to describe the reaction of CO2
with aqueous MEA / TEA solutions. In this study, the thermophysical properties such as
density, viscosity, solubility and diffusivity were also measured.

The hybrid kinetic model is satisfactory representing the reaction of carbon dioxide with
aqueous monoethanolamine (MEA) and triethanolamine (TEA) solutions. By introducing
MEA into aqueous TEA solution, the CO2 absorption rate can be effectively increased.

並列關鍵字

absorption ； aqueous MEA/TEA solutions

參考文獻

Al-Ghawas, H. A.; Hagewlesche, D. P.; Ruiz-Ibanez, G.; Sandall, O. C. Physicochemical Properties Important for Carbon Dioxide Absorption in Aqueous Methyldiethanolamine. J. Chem. Eng. Data 1989, 34, 385-391.

Alvarez-Fuster, C.; Midoux, N.; Laurent, A.; Charpentier, J. C. Chemical Kinetics of the Reaction of Carbon Dioxide with Amines in Pseudo m-nth Order Conditions in Aqueous and Organic Solutions. Chem. Eng. Sci. 1980, 35, 1717-1723.

Alvarez-Fuster, C.; Midoux, N.; Laurent, A.; Charpentier, J. C. Chemical Kinetics of the Reaction of CO2 with Amines in Pseudo m-nth Order Conditions in Polar and Viscous Organic Solutions. Chem. Eng. Sci. 1981, 36, 1513-1518.

Astarita, G.; Savage, D. M.; Longo, J. M. Promotion of CO2 Mass Transfer in Carbonate Solutions. Chem. Eng. Sci. 1981, 36, 581-588.

Astarita, G.; Savage, D. W.; Bisio, A. Gas Treating With Chemical Solvents; John Wiley & Sons: New York, 1983.