Azo-substituted ethoxyacridine – reagents for the extraction-photometric determination of indium(III)

Abstract

The associates of bromo-indate with azo-substituted ethoxyacridine have been studied by spectrophoto-metric method. It has been found that the associates are well extracted with a mixture of chloroform acetone (4:1). The optimum volume of aqueous and organic phase is equal to 5 ml. The molar ratio of the components in the extractable compounds was studied by the methods of isomolar series, equilibrium shift and a straight line. It was found that bromo-indate associated with azo-ethoxyacridines (AE) in a ratio of 1:1. Study of the effect of foreign ions on the accuracy of the determination of indium with azo-substituted ethoxyacridine showed that the number of ions does not interfere (in parentheses are multiple relationships to indium ions); CdII (1200), NH4+ (4000), Zn2+ (1500), CoII (1100), NiII (1050), CuII (500), FeII (4000), PbII (250), Nb (250), TaV (270), Al3+ (2000), ReVII (140), B3+ (410), C2O42- (1900), CH3COO- (1300), ascorbic acid (270), citrate ion (3500), tartrates (4000), EDTA (3700). Number of ions interfered the determination: TlIII (1), FeIII (1), Ga3+ (1), HgII (1), SbV (1), AuIII (1), thiourea (4). It was studied formation and extraction of associates of bromo-indate with AEADPA (2-ethoxy-6-(4-N,N-dipropylphenylazo)-9-aminoacridine) and AEADEA (2-ethoxy-6-(N,N-ethylphenylazo)-9-aminoacridine). The maxima of light absorption of bromo-indate with AEADPA is observed at 530 nm, and the AEADEA at 515 nm. The physico-chemical and analytical characteristics of the azo-substituted ethoxyacridines and their ionic associates with indium bromide acid complexes (λmax ε, βkD, D, R%) were determined. It was shown that bromo-indate compounds with azo-substituted ethoxyacridines are ionic associates, the molar ratios of the components in which are: [İn III] : [Br -] : R + = 1:4:1. Highly efficient extraction-photometric methods have been developed for the determination of trace amounts of indium in various objects.