INTERNATIONAL RESEARCH JOURNAL OF SCIENCE AND ENGINEERING

1-10

Authors: Gupta Swaroopa Rani N

Formaldehyde is widely used in the manufacture of many resins, polymers, and construction materials. It is also used as a preservative, disinfectant, and biocide. Formaldehyde is one of the volatile organic compounds that are widely used in household materials, which is associated with many health risk factors. Acetaldehyde is a Group 1 carcinogen. Propionaldehyde is used in the manufacture of plastics, in the synthesis of rubber chemicals, and as a disinfectant and preservative. Present paper deals with Polarographic determination of formaldehyde, acetaldehyde and propionaldehyde by calibration method. In alkaline medium it is possible to have well defined and separated waves relative to the reduction of formaldehyde, acetaldehyde and propionaldehyde. The determination of these aldehydes are carried out effectively in presence of 3.8 x 10-6 % methyl red and 5.94 x 10-7 % bromocresol green as maxima suppressor and 0.025 N lithium hydroxide and 0.0025 N lithium chloride as supporting electrolyte at pH 12 by calibration method. Polarograms of all systems were recorded on Toshniwal maual polarograph using Dropping Mercury Electrode as cathode and Saturated Calomel Electrode as anode. The determination error is 0 % with low standard deviation. The values of E1/2 ranges from -1.692 to -1.772 V for formaldehyde, -1.490 to -1.514 V for acetaldehyde and -1.600 to -1.590 V for propionaldehyde. From a comparison with the understood polarographic behavior of these aldehydes, number of electrons (n) involved in the reduction is found to be 2. Formaldehyde, acetaldehyde and propionaldehyde give a single well defined reduction wave of irreversible nature.