Spectrophotometric Determination of Aldehydes in Alcohols

Abstract
A simple and sensitive method was described for the determination of formaldehyde and acetaldehyde in methanol and ethanol, respectively. A limit for aldehydes in alcohols is a necessary requirement. This method is based on the reaction between the aldehydes and 3-methyl-2-benzothiazolone hydrazone with t h e formation of coloured products. The sensitivity of the method was enhanced by applying the second - derivative technique to cover the concentration range of 0.05 - 0.25 ug/ml of either aldehyde in the corresponding a lcohol with CV % less than l %s. Moreover, the detection limit:vas lowered t o 10 ng/ml.