Determination of formic acid in the presence of other acidic media

Abstract

In the presence of other acidic media (inorganic or organic acids) and formaldehyde, the analysis of trace amounts of formic acid is a difficult problem. Analyzing trace amounts of formic acid using chemical methods is susceptible to interference from other acidic substances. Although the selective oxidation method can determine trace amounts of formic acid in the presence of oxalic acid and acetic acid, the procedures are cumbersome and the oxidant is difficult to prepare. Ahman used gas chromatography to analyze volatile fatty acids and pointed out that trace amounts of formic acid were impossible to detect with a flame ionization detector, and the sensitivity of thermal conductivity was low. Someone once used a flame ionization detector to detect performic acid, but the response value was very small. It is reported that ion exchange liquid chromatography can detect 0.1ppm formic acid, but the processing method is complicated and not suitable for factory control analysis.