Determination of formic, acetic, propionic, and n-butyric acids by indirect photometric chromatography.

Zhao, Wenying; Wu, Zhiqiang; Fan, Zhixian; Xiang, Shuguang

An indirect photometric chromatography (IPC) method was developed for the determination of formic, acetic, propionic and n-butyric acids using high-performance liquid chromatography with ultraviolet detection. The chromatographic separations were performed on a Waters SymmetryShield PR8 column with a diphenylguanidine aqueous solution as the mobile phase and the pH value was adjusted by n-butyric or n-pentanoic acid. The forming mechanism of the ion-pairing compounds was discussed. The effect of the column, the kind, and concentration of ion-pairing reagents and modifiers were investigated. The results showed that the linear relationships of the four kinds of acids all performed well and the correlation coefficients (R2) were all above 0.996. The established method had a good precision and accuracy for the acids. The IPC method was also compared with a titrimetric method for determining the sample content. Additionally, to eliminate the errors caused by the different backgrounds between the standard solutions and complex sample solutions, a standard additive method was explored for the analysis of a mixture of acids. The established method is simple, efficient, and accurate for determining C1 to C4 linear chain saturated monocarboxylic acids.

MONOCARBOXYLIC acids; DIPHENYLGUANIDINE; HIGH performance liquid chromatography; FORMIC acid; ACETIC acid; BUTYRIC acid

Journal of Liquid Chromatography & Related Technologies, 2018, Vol 41, Issue 9, p481

1082-6076

Academic Journal

10.1080/10826076.2018.1465434