Electrochemical removal of gaseous elemental mercury in liquid phase with a novel foam titanium-based DSA anode

The dimensional stable Ti/Sb-SnO2/PbO(2)( )electrode was prepared by the impregnation method. To remove gaseous elemental mercury (Hg-0) from coal combustion, the study of Hg-0 oxidation was performed in a gas diffusion electrochemical reactor with the stainless steel mesh cathode and the Ti/Sb-SnO2/PbO2 anode. Hg-0 is oxidized into highly water-soluble oxidation states of mercury as a result of the loss of electrons on the anode, which can be removed later utilizing WFGD and other devices. By investigating the effects of applied voltage, the concentration and pH of the electrolyte, reaction temperature, flue gas flow and initial Hg-0 concentration on removal, the appropriate conditions for the experiment were obtained. At the pH of 3, the removal efficiency can reach over 90%, which is about 1.7 times the removal of a single foam Ti under the same conditions.