醇胺在醇胺水溶液中之擴散係數量測

Measurements of Diffusion Coefficients of Alkanolamines in Aqueous Alkanolamines Solutions

林東億(Tung-Yi Lin)

指導教授 ： 李夢輝

中原大學/工學院/化學工程研究所/碩士(2003年)

https://doi.org/10.6840/cycu200300658

摘要

本研究為量測醇胺（MEA; DEA; MDEA; AMP）分別在醇胺水溶液（MEA+H2O; DEA+ H2O; MDEA+ H2O; AMP+ H2O）之擴散係數數據。溫度範圍將為30℃至70℃；醇胺水溶液濃度範圍：0.5至4.0 kmol/m3。
醇胺在溶液中之擴散係數將利用根據泰勒分散法（Taylor dispersion method）之原理來測量，設備包括一50m之毛細管（id-0.01 inch）、六向脈衝溶質注入閥、精密流速控制計、折光率分析儀等；本實驗設備係改良Snijder et al. (1993)所提之設計來裝置。實驗中之設備規格（毛細管之管長管徑比、毛細管曲率半徑）及操作條件（流體流速）皆須符合泰勒分散法之適用範圍，由所得之高斯分佈曲線可求得醇胺在醇胺水溶液中之擴散係數。
近年來混合醇胺水溶液被提出以為新的酸性氣體吸收液之相關研究已逐漸展開。醇胺水溶液之物性數據如密度、黏度、比熱及氧化亞氮在醇胺水溶液之亨利常數、擴散係數以推算二氧化碳醇胺水溶液之亨利常數、擴散係數等數據，近年來已陸續出現在文獻中。酸性氣體與醇胺水溶液之反應動力學探討除上述熱物性數據外尚須醇胺在醇胺水溶液之擴散係數，而醇胺在醇胺水溶液之擴散係數數據，目前文獻上則尚欠缺。故本研究之目的即為有系統之量測醇胺在醇胺水溶液之擴散係數，所得之成果可用來求得二氧化碳與醇胺水溶液之正確反應動力學數據，以作為設計吸收設備之計算依據。

關鍵字

泰勒分散法 ； 擴散係數

並列摘要

The study present the measurement of the diffusion coefficients of amines in aqueous alkanolamine solutions. The alkanolamines considered are: primary amines: monoethanolamine(MEA); secondary amine: diethanolamine(DEA); tertiary amine: methyldiethanolamine(MDEA), and sterically hindered amine: 2-amino-2-methyl-1-propanol(AMP). The temperature range will be 30 to 70℃, and the concentration of amine will be from 0.5 to 4.0 kmol/m3.
The diffusion coefficient of amine in aqueous alkanolamine solution will be determined based on the Taylor dispersion technique. The experimental setup was base on the apparatus proposed by Snijder et al. (1993) will be followed with some modifications. The apparatus includes a 50-m (id-0.01 in)capillary, six way injection valve, mass flow controller, and refractive index detector.
Physic-chemical properties, such as density, viscosity, heat capacity, the Henry law and diffusivity of acid gases in amine systems, and diffusivity of amine in aqueous amine solutions are required in the design calculation. However, only quite few data are available for the diffusion coefficients of amine in aqueous alkanolamine solutions. Thus, the result of this study can be used as the data base for diffusion coefficient of amine in aqueous amine solutions to calculate the accurate kinetic reaction rate constants which in turn to estimate the mass transfer coefficient.

並列關鍵字

Taylor dispersion method ； diffusion coefficient

參考文獻

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