Patent ID: 8293534

Claim:
A method for quantifying permanganate-reducing compound (PRC) content of an acetic acid sample, comprising: (a) establishing a correlation between permanganate absorbances of standard samples and their PRC content by: (i) preparing two or more standard samples with known PRC contents; (ii) adding a known amount of a standard permanganate solution to each standard sample from (a)(i) to form a mixture; (iii) for each standard sample, measuring the absorbance of the mixture (A mix ) at a selected wavelength in the range of 460 to 580 nm at a set reaction time; (iv) for each standard sample, determining the permanganate absorbance (A perm ) at the set reaction time by subtracting from A mix the absorbance due to manganese dioxide (A MnO2 ) at the selected wavelength; (v) establishing a correlation between permanganate absorbances and their PRC contents; and (b) repeating steps (a)(ii) through (a)(iv) with the unknown acetic acid sample that contains an unknown amount of PRC to determine its PRC content.