Competitive oxidation effects during the ozonation of ammonia and nitrite containing tannery wastewater

摘要

The competitive oxidation of ammonia and nittite and organic compounds containing tannery wastewater were investigated. The oxidation of ammonia in organic-free water showed a change of the kinetic regime with a K_(NH3) (pseudo 1. order) of 11.3 +- 1M~(-1) s~(-1), whereas the oxidation of nitrite was ozone-limited. The oxidative COD- and DOC-removal from tannery wastewater was significantly delayed and the additional consumption of ozone could be recalculated and well ascribed to the simultaneous oxidation of the N-species, using the corresponding molar ozone consumption coefficients of Y_(M-NH3)=2.4 mole O_3/mole NH_3 at pH 9 and Y_(M-NO_2)=0.93 mole O_3/mole NO_2 at pH 7, rsp.