[Experimental research of purification NO-containing gas by aqueous oxidation with UV/H2O2]

The influence of some experimental factors on removal efficiency of nitric oxide (NO) under the condition of liquid-phase oxidation with UV/H2O2, such as H2O2 concentration, solution temperature, initial pH, NO concentration, illumination condition, O2 content and gas flow rate, were investigated by employing orthogonal experiments and single factor experiments. The results showed that NO could be efficiently removed by the aqueous oxidation technology with UV/H2O2 system, and the highest NO removal rate was about 80%. Moreover, H2O2 concentration, temperature and initial pH had varying degree effects on purifying NO-containing gas, whereas NO removal rate were more affected by H2O2 concentration and temperature. The single factor experimental results showed that high NO removal rate could be obtained when H2O2 concentration was 0.2 mol/L and the initial pH was 6-7. H2O2 concentration and initial pH should be maintained at an appropriate level or the production of *OH could be restricted, which would result in lower NO removal rate. The optimum operation temperature was 40 degrees C, which is lower than common operating temperature (50 degrees) for the wet scrubber. Enlarging the illumination strength and O2 content could improve the NO removal rate. Furthermore, the NO removal rate was also controlled by the area and coefficient of gas-liquid mass transfer.