CLAY-MINERALS OF PERIYAR RIVER SEDIMENTS AND THEIR ROLE IN THE UPTAKEOF CADMIUM AND NICKEL

Clayey sediments collected from Periyar river were characterized using chemical analysis, XRD, DTA, TGA, cation exchange capacity determinat ions and surface area measurements. Studies indicate that kaolinite do minates the clay minerals in the region followed by illite, chlorite a nd smectite. Mineral impurities include quartz, feldspar and gibbsite. Cation exchange capacity and surface area measurements do not vary mu ch among the samples, i.e. 18-23 meg/100 g and 14-20.16 m(2)/g respect ively. Adsorption/ion-exchange studies with river sediments. revealed selectivity of these clays to nickel than cadmium and helped in illust rating their role in the control of metal pollution.