The adsorption of mercuric chloride vapours on a fixed bed of calcium hydroxide fine particles has been experimentally studied. The study has been conducted at laboratory scale using simulated flue gases, constituted of mercuric chloride vapours in nitrogen, which have been in contact with a Ca(OH)2fixed bed. The effect of the bed temperature, the inlet HgCl2concentration, and the relative gas-solid velocity on the HgCl2removal efficiency has been studied. The experimental results indicated that high removal efficiencies of up to 95 can be obtained. The bed temperature has been found to be the most relevant parameter; particularly as the experimental results show that the lower the bed temperature, the higher the removal efficiency. Moreover, the removal efficiency increases when the HgCl2concentration in the inlet gas increases and when the relative gas-solid velocity decreases. A model based on a simplified expression of the Freundlich adsorption isotherm has been proposed, which is able to describe quite accurately the dependence of HgCl2removal efficiency on the parameters investigated
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