Application of electrochemical technique to measure mass transfer of macromolecules in a flow system.

Abstract

Steady state voltammetry and the scanning methods were used to obtain voltammograms (current-potential curves) with well defined mass transfer regions.

The Reynolds numbers were 7174, 10782, and 14307. The Schmidt number was held constant at 4730.

The discrepancy among the experimental and literature-based values was in the range of 46% to 62%. This is due to the fact that the correlations cited in the literature were developed for simple molecules.

The experimental local mass transfer coefficients (k's) were 2.43 x 10('-3), 3.15 x 10('-3), and 3.35 x 10('-3) cm/sec at Re = 7.74, 10782, and 14307 respectively. These experimental values of k's were compared with the literature by using the expression,

The electrochemical technique was used to study the mass transfer rates of macromolecules in a flow system. The direct oxidation of NADH was the electroactive species. The flow system consisted of rectangular duct. Glassy carbon disc electrodes were used as the working electrodes. A platinum sheet was used as the counter electrode, and the reference electrode was Ag/AgCl.

(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI)