Ternary diffusion coefficient measurements for monoethanolamine (MEA) + Triethanolamine (TEA) + water (H2O) system

• Main Authors: Wen-Hao Chang, 張文豪
• Other Authors: Meng-Hui Li
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/17338596546588271704

碩士 === 中原大學 === 化學工程研究所 === 95 === The ternary diffusion coefficients of aqueous blended alkanolamine systems Ethanolamine (MEA) + Triethanolamine (TEA) + water were measured to use the Taylor dispersion method for 30、35 and 40 oC. The ternary diffusion coefficients were reported for solutions containing the total amine concentrations, 2 and 3 kmol·m-3 for three amine concentration ratios. The corresponding mutual diffusion coefficients of aqueous MEA and aqueous TEA solutions were also measured. In the Taylor dispersion experiment, a solution is injected into a laminar carrier stream of reference fluid which flows in a long capillary tube and the injected solutes spread out as the mixed flow along the capillary tube. The concentration profiles of diffused solutes were determined by a refractive index detector. Final using regression procedure to calculate the ternary diffusion coefficients from the concentration profiles of mixed solutions. The main diffusion coefficients (D11 and D22) and the cross coefficients (D12 and D21) were related to functions of temperature and concentration of alkanolamines. The correlation between the diffusion coefficients on the compositions and the temperature and viscosity were discussed. Final using the Onsager model to calculate of the main diffusion coefficients (D11 and D22) and the cross coefficients (D12 and D21) from the activity and the partial molar volume of components were also performed. The experimental results can be used to determent the effect of presence of diffusivities alkanolamine on diffuse of the mixtures and the values can be directly applied in modeling CO2 absorption in the wetted wall column.