Correction of hydrogen peroxide interference on standard chemical oxygen demand test

The chemical oxygen demand test, which is widely used as an indicator to id entify the characteristics of wastewater, could be disturbed by the inorgan ic substances such as nitrite, chloride, hydrogen peroxide, etc. For hydrog en peroxide differently to the other inorganic substances, the method of ov ercoming its interference is not mentioned in Standard Methods [APHA (1995) Standard Methods for the Examination of Water and Wastewater, 19th edition . Washington, D.C.] and is also reported insufficiently in the literature u ntil now. This work has been carried out to Correct quantitatively the effe ct of the concentration of hydrogen peroxide on the chemical oxygen demand. The ratio of the chemical oxygen demand to the concentration of hydrogen p eroxide is affected by its concentration and is increased up to 0.4706, whi ch is the theoretical value, with decreasing its concentration. The correla tion equation, which can be applied to the hydrogen peroxide concentration range of 0-2000 mg/l, is proposed to correct the effect of the concentratio n of hydrogen peroxide on the chemical oxygen demand. It is also shown that this correlation equation can be applied to the samples containing hydroge n peroxide and organic substances. (C) 1999 Elsevier Science Ltd. All right s reserved.