Synthesis and Characterization of Bismuth Based Novel Inorganic Ion Exchange Materials and Their Analytical Applications.

Abstract

Two new inorganic ion exchange materials Bismuth(III) antimonotungstate(BiSbW) and Bi(III) iodotungstate(BiIW), salts of heteropoly acids were compared to evaluate their performance as ion exchangers and to explore their efficacy as dye adsorbents. Amorphous BiSbW and BiIW have been synthesized by co-precipitation methods by varying the mixing ratio of the reagents. The most stable samples of BiIW and BiSbW have been characterized for spectral analysis (FTIR), elemental analysis (SEM-EDS), thermal analysis (TGA and DTA) and X-ray diffraction studies. Their ion exchange capacities for Na + ions were found to be 0.85 meqg -1 (BiSbW) and 2.25 meqg -1 (BiIW). The effect on the exchange capacity of drying the exchanger at different temperatures has been studied. The distribution coefficient values shows that these two samples are very selective for Pb 2+ ions. Hence their analytical importance has been established by quantitative separation of Pb 2+ from other metal ions and quantitative removal of Pb 2+ ions from textile industry. The adsorption results also reflected the vital influence of the new materials in controlling the hazardous organic pollutants by adsorption of various dyes from waste water.