Polyelectrolyte effect on spectrophotometric determination and interaction of scandium (III) with eriochromcyanine

Abstract

The influence of cationic water-soluble polyelectrolyte PSPMG on the interaction of scandium (III) with organic reagent eriochromcyanine is studied. Because the study of the possibility of obtaining new, more effective, modified reagents with a complex of better analytical characteristics is an actual analytical task. The optimal conditions of complex formation were experimentally determined: the pH range (5.5–6.5), the order of the adding of the components (1 – scandium, 2 – ECR, 3 – PSPMG, 4 – buffer solutions), the composition of the Sc-ECR-PSPMG complex (1:4:1) were experimentally determined and the molar absorption coefficient – 1.8·10 5 was calculated. A sensitive spectrophotometric method for scandium determination in solutions at the level of 10 -7 mol/L was developed. The optimal scandium sorption parameters in the form of three-component systems Sc-OR-modifier on solid-state carriers were established, scandium sorption isotherms were constructed, sorption parameters of A gran and K ads were calculated. The test systems for the identification of scandium as ternary compounds in polyurethane foam and cotton were proposed, calibration curves in the concentration range from 1·10 -6 –1·10 -5 mol/L were built and the colorimetric method of identification of scandium in solutions that accelerate analysis was proposed. It is shown that the PSPMG application is a promising direction for improvement of chemical-analytical characteristics of organic reagents (eriochromcyanine and chromazurol S) because its usage increases the sensitivity and selectivity of the spectrophotometric determination of scandium in the form of a complex Sc-OR-PSPMG.