Extraction-Chromogenic Systems for Gallium(III) Based on Azo Dyes and Xylometazoline Hydrochloride

• Published in: Russian journal of general chemistry 2020-07, Vol.90 (7), p.1351-1356
• Main Authors: Racheva, P. V., Hristov, D. G., Gavazov, K. B.
• Format: Article
• Language: English
• Subjects: Absorptivity; Advertising executives; Azo dyes; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chloroform; Gallium; Liquid-liquid extraction; Reagents; Spectrophotometry; Xylometazoline
• ISSN: 1070-3632; 1608-3350
• DOI: 10.1134/S1070363220070245

Two liquid-liquid extraction-chromogenic systems for Ga III based on azo dyes (ADs) and xylometazoline hydrochloride (XMH) have been studied. The ADs used were 4-(2-pyridylazo)resorcinol (PAR) and 4-(2-thiazolylazo)resorcinol (TAR). The optimum conditions (pH, AD concentration, XMH concentration, and extraction time) for the formation of ternary complexes of general formula (XMH + )[Ga III (AD 2– ) 2 ], that are readily extracted into chloroform, have been worked out. The following extraction-spectrophotometric characteristics: absorption maxima (λ), molar absorptivities (ε λ ), limits of detection (LOD), limits of quantitation (LOQ), constants of extraction ( K ex ), and fractions extracted ( E ) have been determined. The system in which AD = PAR has better performance: ε 512 = 9.9×10 4 dm 3 mol –1 cm –1 , LOD = 2.8 ng/cm 3 , LOQ = 9.4 ng/cm 3 , log K ex = 4.1, and E = 97%. Extraction equilibrium with this reagent is achieved in a short time (only a few seconds) and the optimum pH interval is broad (5.1–7.8).