Degradation of Refractory Organic Pollutants byCatalytic Ozonation -Effect of Water Background

摘要

A bench-scale, laboratory study is carried out to investigate the effectrnof water quality on MnOx/GAC heterogeneous catalytic ozonation.rnWith the increase of pH the degradation efficiency of nitrobenzenernincreases in the case of ozonation, but decreases in the case of catalyticrnozonation. The presence of magnesium ion, chloride, nitrate andrnbicarbonate has limited negative effect on the heterogeneous catalyticrnozonation. It is suggested that the negative effect may be due to therninteraction between inorganic ions and the surface of metal oxides.rnLow concentrations of humic substances (≤ 1 mg/L, as DOC) greatlyrnenhances the degradation of nitrobenzene for both the catalyticrnozonation and ozone oxidation alone; however, higher concentrationsrnof humic substances have less degradation efficiency. It is alsornobserved that the effect of humic acid on the adsorption of nitrobenzenernis limited. In tap water, which contains some inorganic and organicrnsubstances, the degradation efficiency is lower than that in distilledrnwater.