Use of Current and Potential Fluctuations Among Identical Electrodes to Determine the Induction Time of the Transesterification Reaction

摘要

Fluctuations of potential and current generated among identical electrodes (electrochemical noise, EN)immersed in the reaction mixture of a transesterification process were used to determine the timeperiod of the mass transfer controlled stage. The alcohol type (methanol or ethanol), and agitationspeed (200, 400, and 600 rpm) were used to illustrate the potential application of EN in biodieseldevelopment. EN has shown to be particularly valuable for determining the induction time of thetransesterification reaction which is known as a stage of mass transfer control. Thin layerchromatography and thermogravimetric analysis were used to determine the chemical composition ofthe reaction mixture before and after the mass transfer controlled region. These results were correlatedwith electrochemical noise. It was demonstrated that current and potential fluctuations provide arelatively easy way to measure the elapsed time of the initial stage of mass transfer control during thetransesterification process. Therefore current and potential fluctuations are a valuable tool for novelexperiments during the early stages of transesterification.