FIXED-BED COLUMN OF SURFACE MODIFIED ACTIVATED CARBONS FOR ADSORPTION OF MERCURY (II) IN AQUEOUS SOLUTION

摘要

Activated carbons are universal adsorbents that can be obtained from a wide variety of raw materials, and have been found to be very effective for mercury removal from water. This contribution presents a comparative adsorption in column study of activated carbons obtained by physical activation of carbonized eucalyptus wood with water vapour, as adsorbents of mercury in liquid phase. Two samples were treated with sulphuric acid and with carbon disulphide, in order to introduce sulphur as a heteroatom onto the adsorbent surface. Adsorption in column assays was performed and the breakthrough curves were used to compare their performance. The sulphurization treatments produce important variations on the textural properties of the solid, on the zero charge point, and on the number of acid and basic surface groups. From the analysis of these factors, the dependency of the adsorption capacity of a solid with the pH of the solution can be explained.