Ultraviolet spectrophotometric method for the determination of aromatic amines in chemical industry waste waters

Abstract

An analytical method was developed for the determination of aromatic amines occurring in coal processing products. The method involves the measurement of difference UV spectra whereby aqueous solutions of identical concentration but different pH are measured against each other. A detection limit of ca., 0.1–1 mg l^–1(0.1–1 ppm) was achieved. The method is suitable for the determination of aniline and pyridine and their methyl derivatives, and quinoline and isoquinoline in aqueous solutions. The concentrations of individual components or specific groups, were evaluated from the values of peak absorbance (irrespective of the sign) and from the average absorbance for individual groups of compounds. The method was tested for standard mixtures and samples of the amines isolated from coke processing products. The method has potential for determinations in waste waters and industrial effluents where other analytical techniques (e.g., gas chromatography or titration in nonaqueous media) prove difficult.