A process is proposed for the removal and recovery of mercury from combustion flue gas with simultaneous control of SO_2 and NO_x. The approach is based on regenerative adsorption on activated carbons derived from used tires. The flue gas is used as a sorbent regenerating agent. Preliminary data from packed-bed experiments indicate the general feasibility of the method. Mercury sorption was found to be enhanced by the presence of oxygen and nitric oxide, with nitric oxide having a stronger effect. The adsorbed mercury desorbed upon heating. Surface activity was temporarily reduced after each desorption event, but was recovered upon contact with the flue gas. This transient loss of activity can be explained by the necessity to restore the inventory of reactive surface species after each desorption step.
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