Experimental Investigation of Simultaneous Removal of SO2 and NOx Using a Heteropoly Compound

Aiming at developing a simple, feasible method for SO2 and NOx removal, in this work, various doping amounts of heteropolyacid and heteropolyacid salts were prepared and used in wet absorption for simultaneous removal of SO2 and NO. The desulfurization and denitrification performance was evaluated by investigating dynamic SO2 and NO absorption in a simulated reactor containing a heteropoly compound (HPC) solution along with various factors influencing the reaction. The results demonstrate that this system had a high removal efficiency of SO2 and modest NO removal. The amount of Wolfram (W) doping and the pH of the solution affecting the removal performance was studied, and a stable SO2 removal efficiency higher than 95% was obtained for HPW1Mo at a pH value of 5.5. In addition, the desulfurization performance of NaPWMo with a 50% removal efficiency was higher than that of the HPWMo solution (20%) after a 60 min reaction time. A high concentration of the NaPWMo solution and the presence of O2 were beneficial to desulfurization at room temperature. In addition, the removal efficiency of SO2 or NO by NaPWMo was only affected by its own gas concentration rather than their mutual influences on each other. This work should be beneficial to the optimization leading to the development of simultaneous desulfurization and denitrification systems in practical applications.