Heterogeneous catalytic ozonation of P-chloronitrobenzene promoted by waterglass- supported zinc hydroxide in water using continuous flow mode

Waterglass-supported zinc hydroxide, a stable and efficient catalyst prepared in the laboratory, has been successfully used in the decomposition of ozone and trace quantities of p-chloronitrobenzene in water in continuous flow test. The decomposition rate of aqueous ozone was increased with the increase of waterglass-supported zinc hydroxide dose, and the ozone decomposition was affect by the solution pH value. Increasing the catalyst adding amount from 0mg/Lto 500mg/L the removal efficiency of p-chloronitrobenzene was from 0 to 97.5%, and the degradation efficiency increasing with the residence time prolonging. Furthermore, the existing HCO₃^-could inhibit the ozonation process of the p-chloronitrobenzene, the degradation efficiency of p-chloronitrobenzene is between 83% and 42% as the HCO₃^- concentration in the range of 50-200 mg/L. After 3d continuous stable operation in the continuous flow mode test, the catalyst remained stable in the catalytic ozonation of p-chloronitrobenzene.