ADSORPTION OF MERCURY, CADMIUM AND LEAD FROM AQUEOUS SOLUTION ON HEAT-TREATED AND SULPHURIZED ACTIVATED CARBON

The adsorption of mercury, cadmium and lead from aqueous solutions on heat-treated and sulphurized activated carbon has been studied comparatively. The adsorption isotherms for the various metals were measured at 298 K, using adsorptive solutions at two pH values. The adsorption was much higher for mercury than for cadmium and lead for all adsorbents. The adsorption of mercury greatly increased for the samples of sulphurized carbon and also, though less, for the sample prepared in N2. The decrease of pH in the adsorptive solution to pH 2.0 drastically reduced the adsorption of mercury. The effect of pH change on the adsorption of Cd2+ and Pb2+ occurred with less adsorbents than for mercury. © 1998 Elsevier Science Ltd. All rights reserved