Synthesis, characterization and photolytic degradation activity ofAnalytical application in metal ion treatment

A new hybrid cation exchanger poly-o-toluidine–thorium(IV)molybdophosphate (POT-TMP) has been synthesized using sol–gel method by the incorporation of inorganic precipitates of thorium(IV)molybdophosphate into the matrices of organic poly-o-toluidine. The product formation was optimized by varying the synthesis conditions at pH of 1.0. Ion exchange capacity, pH titration, effect of calcinations, chemical stability and distribution behavior of the exchanger were also studied. Activation energy calculated from Arrhenius plot using Broido equation was found to be 7.94 KJ mol−1 at 50 °C. The distribution coefficient values of metal ions determined in different solvent media show the selectivity of the hybrid exchanger for Hg2+ and Pb2+ ions. The analytically important separations of metal ions have been successfully achieved using columns packed with this exchanger. The practical utility of the material was shown by qualitative as well as quantitative determination of Pb2+ and Hg2+ in the synthetic mixtures and industrial effluents. The limit of detection (LOD) evaluated for Pb2+ and Hg2+ was found to be 1.53 and 0.72 μg L−1 respectively. The photocatalytic degradation of Congo red dye using the composite under natural sunlight shows that about 74% of Congo red dye was degraded within 8 h of photo irradiation. © 2015 Elsevier B.V. All rights reserved.

The poly-o-toluidine–thorium(IV)molybdophosphate cation exchanger has been synthesized which possesses the characteristic features of a hybrid ion exchange material such as good ion exchange capacity, high chemical and thermal stabilities, and selectivity. The synthesized material is thermally stable up to 400 °C with the retention of 88.52% of initial ion-exchange capacity. The regeneration ability was also found to be significant as only about 10% of original capacity was lost after six cycles of use. Congo red dye was photolytically degraded by the exchanger that implies its potential as an advanced photocatalyst for the degradation of reactive textile industry dye from water sources. In addition, the exchanger was found to be selective for Pb2+ and Hg2+ metal ions thereby showing its great potential for the removal of toxic metal ions from wastewater. Acknowledgment