The adsorption of heavy metals by different sorbents under various incineration conditions

The emission of heavy metals can be controlled by adding solid sorbents into the combustion chamber during incineration processes. The objective of this work was to experimentally study the adsorption efficiency of different sorbents for heavy metals under various incineration conditions. Each sorbent has its optimum operating temperature. Kaolinite and aluminum oxide have the best adsorption efficiency at 800°C, and bauxite is at 700°C. The adsorption efficiencies of the three sorbents for the four heavy metals all follow the sequence of Pb > Cu > Cr >Cd. The presence of inorganic chloride (NaCl) and sulfate (Na2SO4) increases the adsorption efficiency of the sorbents, but organic chloride PVC decreases the adsorption efficiency.