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要有效設計酸性氣體吸收設備必須具備完整的氣液平衡，物理溶解度、擴
散係數、反應動力學及質傳係數等數據。以前工業上主要利用單一醇胺水
溶液來處理酸性氣體。但近年來混合醇胺逐漸取代單一醇胺溶液，因為混
合醇胺溶液結合了各醇胺的吸收特點。其具備了單一醇胺無法兼具的高吸
收速率，高吸收容量的優點，所以逐漸為工業界所採用。文獻中對混合醇
胺的探討有： (1).CO2與MEA / MDEA水溶液於298 K之動力學數據(
Versteeg et al., 1990)。 (2).CO2與MEA / MDEA水溶液之氣液平衡數
據( Austgen et al., 1991 @ ; Li and Shen , 1992)。 (3).H2S與
MEA / MDEA水溶液之氣液平衡數據( Li and Shen , Shen , 1992 ) ；H2
S與MEA / AMP水溶液之氣液平衡數據( Li and Chang , 1994 )。本研究
主要是探討二氧化碳在混合醇胺水溶液中之物理溶解度及擴散係數。由於
二氧化碳會和醇胺溶液起化學反應，所以我們使用和二氧化碳有相似分子
結構、分子體積和電子構造的氧化亞氮來取代二氧化碳。再利用``氧化亞
氮 類比''原理來求得二氧化碳的數據。本實驗所探求的醇胺水溶液組成
為： 30 wt% MEA，24 wt% MEA + 6 wt% AMP，18 wt% MEA + 12 wt%
AMP ， 12 wt% MEA + 18 wt% AMP，6 wt% MEA + 24 wt% AMP，30 wt%
AMP 及 24 wt% MEA + 6 wt% MDEA，18 wt% MEA + 12 wt% MDEA，12
wt% MEA + 18 wt% MDEA，6 wt% MEA + 24 wt% MDEA，30 wt% MDEA；溫
度範圍是30 ，35 ，40℃。同時並建立半經驗式的模式來預測實驗數據。
The solubility (physical) and diffusivity of acid gases of N2O
and CO2 in aqueous MEA (monoethanolamine) / MDEA (N-
methyldiethanolamine) solutions and MEA (monoethanolamine) /
AMP (2-Amino-2-methyl-1-propanol) solutions have been measured
for temperatures 30, 35, and 40℃. The systems studied are 30
wt% MEA, 24 wt% MEA + 6 wt% AMP, 18 wt% MEA + 12 wt% AMP, 12
wt% MEA + 18 wt% AMP, 6 wt% MEA + 24 wt% AMP, 30 wt% AMP, 24
wt% MEA + 6 wt% MDEA, 18 wt% MEA + 12 wt% MDEA, 12 wt% MEA + 18
wt% MDEA, 6 wt% MEA + 24 wt% MDEA, 30 wt% MDEA. The solubility
data of N2O in amine solutions were measured in a solubility
apparatus. The diffusivity data of N2O in amine aqueous
solutions were measured in a wetted wall column apparatus.
Using the N2O analogy, the solubility and diffusivity of CO2 in
blended amine solutions were estimated. The solubility data
obtained in this study were correlated based on the excess
Henry's coefficient using the volume fraction as concentration.
The results of this study can serve as a valuable data base for
efficient design of acid gas treating processes,using blended
amine as the absorption fluids.
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