Removal of Hg0 and simultaneous removal of Hg0/SO2/NO in flue gas using two Fenton-like reagents in a spray reactor

A novel process on oxidation removal of elemental mercury (Hg-0) from flue gas using two Fenton-like reagents in a spray reactor was proposed. The effects of several process parameters such as H2O2 concentration, Fe3+ concentration, Cu2+ concentration, reaction temperature, solution pH, Hg-0 inlet concentration, liquid-gas ratio, NO concentration, SO2 concentration on Hg-0 removal were investigated. Reaction mechanism of Hg-0 removal was investigated. Simultaneous removal of Hg-0, NO and SO2 in flue gas was studied preliminarily. A simple economic estimate for simultaneous removal of Hg-0, SO2 and NO was also carried out. Increasing H2O2 concentration, Fe3+ concentration, Cu2+ concentration or liquid-gas ratio significantly promotes Hg-0 removal. Increasing solution pH, NO concentration or SO2 concentration significantly inhibits Hg-0 removal. Hg-0 inlet concentration and reaction temperature have a small impact on Hg-0 removal. Oxidation of Hg-0 by (OH)-O-center dot plays a leading role for Hg-0 removal. The simultaneous removal efficiencies of Hg-0, SO2 and NO are up to 100%, 100%, 85.3% and 100%, 100%, 75.3% using Fe3+ and Cu2+ as catalysts, respectively. (C) 2015 Elsevier Ltd. All rights reserved.