A   sorbent   based   on   a   copolymer   of   maleic   anhydride   with   styrene,   containing m-phenylenediamine fragments was synthesised. After drying at 50–60 ° С , the obtained sorbent was identified using IR spectroscopy. Further, a study of lead sorption by a synthesised sorbent was conducted. For this purpose, the effect of pH, time, ionic strength and metal concentration on sorption was determined. According to the experiment, the maximum sorption was established at рН = 6. Complete sorption of lead (II) wasobtained following 3 hours of metal contact with the sorbent. The effect of increase in ionic strength to 0.6 mol/L on sorption was shown to be insignificant, with a subsequent increase leading to a critical decrease in sorption value. The isotherm of lead sorption by the synthesised sorbent was constructed and the optimal concentration conditions studied. The analysis results demonstrated an increase in the concentration of lead (II) ions in the solution to provide higher values of sorbed metal concentration with the maximum occurring at a concentration of 6·10 -3 mol/L (pH = 6, С Pb +2 = 6·10 -3 mol/L, V sample = 20 mL, m sorb. = 0.05 g, CE = 405 mg/g). Under optimal conditions, the extraction degree of lead (II) ions exceeds 95 %. The study of sorption was carried out both under static and dynamic conditions. Additionally, the effect of various mineral acids (HClO 4 , H 2 SO 4 , HNO 3 , HCl) of the equal concentration on the desorption of lead (II) from the sorbent was studied. The maximum desorption of lead (II) was obtained in sulphuric acid. Thus, the proposed express technique including preliminary concentration of lead (II) with a synthesised sorbent provides quantitative isolation of lead (II) from a large sample volume with a complex background composition.

The sorption and complexing properties of styrene/maleic anhydride copolymer-based modified sorbent in relation to molybdenum(VI) have been studied and main quantitative characteristics of metal ion sorption have been defined. A sorbent containing p-phenylenediamine fragments has been proposed for selective extraction of molybdenum(VI) from solutions. Optimal sorption conditions are defined. The influence of various mineral acids (HClО4, H2SО4, HNО3, HCl) on molybdenum(VI) desorption from the sorbent has been studied. The experiment has revealed that maximum molybdenum(VI) desorption occurs in sulfuric acid. The molybdenum(VI) extraction rate in optimal conditions exceeds 95 %. Methods of sorption-photometric determination of molybdenum(VI) in sea water have been developed.

It is synthesized a novel sorbent based on maleic anhydride with styrene modified by rubeanic acid. It is studied the static sorption capacity of the sorbent obtained. By potentiometric titration, there are determined ionization constants of ionogenic groups. Sorption isotherm of cobalt (II) ions with the synthesized sorbent is constructed; the optimal conditions of concentrating are investigated. The degree of cobalt (II) ions extraction under optimum conditions exceeds 95%. The technique of sorption photometric identification of cobalt (II) in seawater is developed.

Sorption and complexing properties of a modified adsorbent based on a maleic anhydride-styrene copolymer towards uranium(VI) are studied and the main quantitative characteristics of the metal ion sorption are determined. An adsorbent containing m-aminophenol fragments is proposed for the selective sorption of uranium(VI) from solutions. The optimal sorption conditions have been found. The recovery of uranium(VI) under the optimal conditions exceeds 95%. A procedure of the sorption photometric determination of uranium(VI) in sea water is developed.

The complexation of uranium(VI) with 2,3,4-trihydroxy-3′-nitro-4′-sulfoazobenzene was studied. A complex was formed with the molar ratio of the components 1: 2, the maximum of light absorption at 435 nm, and the molar absorption coefficient 1.00 × 104. A new adsorbent bearing carboxyl groups was synthesized. The batch adsorption capacity of the adsorbent with respect to K+ ions was found, and the ionization constants of the ionogenic groups were determined by potentiometric titration. An adsorption isotherm of uranium was measured and the optimal conditions for preconcentration were found. Under the optimal conditions, the recovery of U(VI) ions was more than 95%. The detection limit was 14.2 ng/mL (3σ, n = 20). A procedure was developed for the adsorption-photometric determination of uranium(VI) in water.

The complexation of molybdenum(VI) with bis(2,3,4-trihydroxyphenylazo)benzidine (H6L) is studied in the presence of 1,10-phenanthroline. A mixed-ligand complex formed with a molar component ratio of 2: 2: 4. The maximum absorbances of the binary and mixed-ligand complexes are observed at 437 and 426 nm, and their molar absorbance coefficients are (9.02 ± 0.02) × 104 and (10.01 ± 0.01) × 104, respectively. It is found that 1,10-phenanthroline affects H6L and improves the complexation characteristics. A procedure is developed for the photometric determination of molybdenum(VI) in seawater after preconcentration.

A method is developed for cadmium and zinc preconcentration on a minicolumn packed with a new chelating polymer sorbent. The effects of the test solution pH and volume, the sample matrix composition, the eluent volume, and the sample and eluent flow rates are studied. Zinc and cadmium in the eluate are determined by flame atomic absorption spectrometry. Under optimal conditions, the determined ion recovery is more than 95%. The detection limits (3σ, n = 20) are found to be 15.0 (Cd) and 17.2 (Zn) ng/mL. The developed method is employed for cadmium and zinc determination in samples of seawater and water obtained after oil pumping.