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The removal of Pb(II), Hg(II) and Cd(II) by activated carbon prepared from bicarbonate-treated rubber wood sawdust has been found to be concentration, pH and temperature dependent. The percentage adsorption of metal ions increased with decrease in initial concentration of metal ions, increase in adsorbent dosage and temperature. The optimum pH range for the removal of ~b(II) and Hg(II) is 4-8 whereas maximum uptake for Cd(II) is in the pH range 5-9. The applicability of Lagergren kinetic model has also been investigated. The equilibrium data at different temperatures fit well with the Langmuir isotherm. Thermodynamic constant (Ko) and standard free energy (t.GO), enthalpy (M?) and entropy (&5°) changes were calculated for predicting the nature of adsorption. The surface mass transfer coefficient as a function of initial adsorbate concentration has been determined. Desorption studies revealed that spent adsorbent can be regenerated and reused by 0.2 M HC!. The presence of heavy metals in the environment can be detrimental to a variety of living species. Therefore, the elimination of heavy metals from water and wastewater is important to protect public health. Many reports have appeared on the development of activated carbon from cheaper and readily available materials for the removal of metals from water':'. Activated carbon derived from rice husk', coconut shell, waste slurry generated from fertilizer plant', peanut huW' and waste tea leaves has been successfully employed for the removal of heavy metals from aqueous solutions. Our search for a cheap readily available starting material has identified sawdust as a potentially attractive material for the production of activated carbon for water treatment. Sawdust is a cheap raw material and in abundant supply. The huge deposit of sawdust around sawmills poses problems in its disposal. Besides its utilization in preparing packing materials it has also been recently used in water pollution control!. The present investigation aims at using bicarbonate treated activated carbon prepared from sawdust, a low cost and highly effective adsorbent for the removal of hea vy metals namely Pb(II), Hg(II) and Cd(I1) from aqueous systems.