DIFFUSION-COEFFICIENTS OF SEVERAL AQUEOUS ALKANOLAMINE SOLUTIONS

The Taylor dispersion technique was applied for the determination of d iffusion coefficients of various systems. Experiments with the system KCl in water showed that the experimental setup provides accurate data . For the alkanolamines monoethanolamine (MEA), diethanolamine (DEA), methyldiethanolamine (MDEA), and di-2-propanolamine (DIPA), correlatio ns for the diffusion coefficient as a function of temperature at diffe rent concentrations are given. A single relation for every amine has b een derived which correlates the diffusion coefficients as a function of temperature and concentration. The temperature was varied between 2 98 and 348 K, and the concentration between 0 and 4000-5000 mol/m3. Fu rthermore, a modified Stokes-Einstein relation is presented for the pr ediction of the diffusion coefficients in the alkanolamines in relatio n to the viscosity of the solvent and the diffusion coefficient at inf inite dilution. The diffusion coefficients at low concentrations are c ompared with some available relations for the estimation of diffusion coefficients at infinite dilution, and it appears that the agreement i s fairly good.