Inexpensive Procedure for Measurement of Ethanol: Application to Bioethanol Production Process

Abstract

We have developed a spectrophotometric method for measurement of ethanol concentration in any unknown sample using a solvent tri-n-butyl phosphate [TBP, non-alcoholic solvent, density = 0.975 to 0.976, solubility in water = 0.028% (w/v)]. Solvent TBP separates ethanol from the non-hydrolyzed substrates that could interrupt the desired result by reacting with dichromate reagent. Oxidation of ethanol with dichromate reagent imparts blue green-colour to the solvent, which is easily detected by Spectrophotomer at 595 nm. Our established method showed similar results performed by relatively expensive Gas Chromatography (GC) method. In our present study we put forth a cheap alternate method for determining ethanol concentration in any aqueous solution.