Abstract:
A novel hollow fiber reactor was used to remove Hg
0 from simulated flue gas by Fenton process.The effects of several parameters and impurity gases such as SO
2、NO and O
2 on removal efficiency of Hg
0 by Fenton process were investigated.The results indicated that the Hg
0 removal efficiency increased first and then decreased upon increasing H
2O
2 concentration,Fe
2+ concentration,initial pH value of solution,and temperature.The optimum conditions were:H
2O
2 concentration of 6 mmol/L, Fe
2+ concentration of 9 mmol/L,initial pH value of solution of 2.5, and temperature of 20℃.The increase in liquid-gas ratio and the residence time (the decrease of gas flow rate) enhanced the removal of Hg
0,while the removal efficiency didn't increase any more when the liquid-gas ratio was over 0.11.Hg
0 removal efficiency exceeded 85% when gas flow rate was 0.6 L/min.SO
2 and NO can inhibit the removal of Hg
0, while O
2 has no obvious impact on Hg
0 removal efficiency.In the hollow fiber reactor,the specific surface area (
a) and mass transfer-reaction coefficient (
kL,
kG) between Fenton reagent and Hg
0 were 270.29 m
-1,8.13×10
-4 m/s,0.786×10
-6 mol/(m
2·s·Pa) (20℃),respectively.