Absorption of NO 2 into aqueous (NH 4 ) 2 SO 3 solution in a stirred tank reactor

Absorption experiments of NO 2 from simulated flue gas into aqueous (NH 4 ) 2 SO 3 solution were performed in a stirred tank reactor under atmosphere pressure. As can be seen from the experimental results, the absorption rate of NO 2 into (NH 4 ) 2 SO 3 solution increases as the (NH 4 ) 2 SO 3 concentration increases from 0.01 to 0.06 mol/L. As the concentration of (NH 4 ) 2 SO 3 solution exceeds 0.06 mol/L, the absorption process becomes gas‐film controlled. And the absorption rate increases with increasing NO 2 inlet concentration but decreases with increasing reaction temperature. Compared with Na 2 SO 3 solution, (NH 4 ) 2 SO 3 solution has higher NO 2 absorption rate. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 465–469, 2013