Dispersion in cylindrical channels on the laminar flow at low Fourier numbers

作者：Kucza Witold^*; Dabrowa Juliusz; Nawara Katarzyna

来源：Analytica Chimica Acta, 2015, 881: 90-97.

DOI：10.1016/j.aca.2015.04.049

• Flow injection system
• Impedance measurements
• Numerical modeling
• Optimization
• Diffusion coefficient

A numerical solution of the uniform dispersion model in cylindrical channels at low Fourier numbers is presented. The presented setup allowed to eliminate experimental non-idealities interfering the laminar flow. Double-humped responses measured in a flow injection system with impedance detection agreed with those predicted by theory. Simulated concentration profiles as well as flow injection analysis (FIA) responses show the predictive and descriptive power of the numerical approach. A strong dependence of peak shapes on Fourier numbers, at its low values, makes the approach suitable for determination of diffusion coefficients. In the work, the uniform dispersion model coupled with the Levenberg-Marquardt method of optimization allowed to determine the salt diffusion coefficient for KCl, NaCl, KMnO4 and CuSO4 in water. The determined values (1.83, 1.53, 1.57 and 0.90) x 10(-9) m(2) s(-1), respectively, agree well with the literature data.

• 出版日期2015-6-30