Combined cation-exchange and extraction chromatographic method of preconcentration and concomitant separation of bismuth(III) with high molecular mass liquid cation exchanger

A selective method has been developed for the extraction chromatographic separation of BiIII with Versatic 10 coated on silanized silica gel (SSG). BiIII has been quantitatively extracted from 0.1 M acetate buffer at the range of pH 5.0-5.5. The result showed that the solution pH, influent volume, flow-rate and solution temperature would affect the sorption of BiIII. The sorbed BiIII was eluted with 0.1 M H2SO4. The extractor system has got good values of exchange capacity (1.42 meq. of H+ g−1 of dry exchanger at 25 °C), break-through capacity (19.75 mg g−1 at pH 5.5) and column efficiencies (300) with respect to BiIII. The positive value of ΔH (12.63 kJ mol−1) and ΔS (0.271 kJ mol−1 K−1) and negative value of ΔG (−68.241 kJ mol−1) indicated that the sorption process was endothermic, entropy gaining and spontaneous in nature. P.F. has been optimized at 76.4 ± 0.3 and the desorption constants Kdesorption (8 × 10−3) and K′desorption (1.4 × 10−1) have been determined. Rf values and selectivity factors for diverse metal ions with respect to that of BiIII have been determined by ion-exchange paper chromatography. BiIII has been separated from synthetic mixtures containing its congeners and other metal ions associated with it in ores and alloy samples. The method was found effective for removal of BiIII from different water samples. A plausible mechanism for the extraction of BiIII has been suggested.