Simultaneous desulfurization and denitrification by microwave reactor with ammonium bicarbonate and zeolite

Abstract

Microwave reactor with ammonium bicarbonate (NH 4HCO 3) and zeolite was set up to study the simultaneous removal of sulfur dioxide (SO 2) and nitrogen oxides (NO x ) from flue gas. The results showed that the microwave reactor filled with NH 4HCO 3 and zeolite could reduce SO 2 to sulfur with the best desulfurization efficiency of 99.1% and reduce NO x to nitrogen with the best NO x purifying efficiency of 86.5%. Microwave desulfurization and denitrification effect of the experiment using ammonium bicarbonate and zeolite together is much higher than that using ammonium bicarbonate or zeolite only. NO x concentration has little effect on denitrification but has no influence on desulfurization, SO 2 concentration has no effect on denitrification. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and dentrification are 211–280 W and 0.315 s, respectively. The mechanism for microwave reduced desulfurization and denitrification can be described as the microwave-induced catalytic reduction reaction between SO 2, NO x and ammonium bicarbonate with zeolite being the catalyst and microwave absorbent.