Experiment on Hg<sup>0</sup> removal from flue gas by sodium chlorite solution

Abstract

The important to enhancing gaseous elemental mercury (Hg <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> ) removal in wet scrubber systems is altering the chemical form of the Hg <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> to a water-soluble oxidized species. Experiments on the removal elemental mercury from simulated flue gas by aqueous sodium chlorite in a bubble reactor were carried out in this work. The effect of initial oxidizing solution concentration, reaction temperature, pH and SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> concentration on mercury oxidative absorption in sodium chlorite were investigated. The results indicate that the higher concentration of sodium chlorite favors Hg <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> removal, whose efficiency is greater in acidic than alkaline solution. High temperature inhibits Hg <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> absorption in aqueous sorbent when reaction temperature is lower than about 40□, and the removal efficiency increases whereas temperature is higher than about 40□. The SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> concentration did not significantly affect the efficiency of Hg <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sup> removal.