クロモトロープ酸を用いるエチレングリコールの比色定量

概要

論文の詳細を見る
Ethyleneglycol is oxidized to formaldehyde and determined colorimetrically by the reaction with either chromotropic acid or 3-methyl-2-benzothia-zolinone hydrazone. It was found that the oxidation of ethyleneglycol with potassium permanganate-sul-furic acid was accelerated by acetaldehyde-ammonia ([CH_3 CH(NH_2)OH]_3). Based on this fact, a procedure for the determination of ethyleneglycol was established. To 1.0 ml of the test solution containing (10〜40) μg of ethyleneglycol, add 0.2 ml of 0.05 w/v % acetaldehyde-ammonia solution, 0.1 ml of 0.25 M sulfuric acid, and 0.1 ml of 1.20 % potassium permanganate solution. Allow the mixture to stand at room temperature for 50 min. Add 0.1 ml of 20 % sodium sulfite solution to reduce excessive permanganate and 0.2 ml of 2 % aqueous chromotropic acid solution. Add slowly 4 ml of 75 % sulfuric acid. Heat the mixture in a boiling water bath for 10min. Upon cooling to room temperature, measure the absorbance at 575 nm against the reagent blank. The calibration curve was linear in a range of (10-40) μg ethylenegly-col/ml, the coefficient of variation being 4.2 %. Methanol and glycerol seriously yielded a positive interference.
社団法人日本分析化学会の論文
1980-02-05