Study On O-phenylenediamine Wastewater Treatment Technology

O-phenylenediamine is main organic pollutants in carbendazim pesticide production wastewater and has toxicity and biological inhibitory effect. It is the main reason for o-phenylenediamine wastewater nonbiodegradable and lack of efficient and economic strengthening pretreatment. This study investigate the effectiveness and feasibility of the metal ions complexation to remove o-phenylenediamine, and focuses on the Fe3+/H2O2joint oxidation effect of remove o-phenylenediamine, in order to obtain the pretreatment process of efficient and economical, and analyze Fe3+oxidation mechanism of remove o-pheny-lenediamine.The result showed that OPD concentration showed a good linear relationship with COD, COD/OPD is1.93. The effect of metal ions complexation to remove o-phenylenediamine is low, actual engineering applications is poor. To COD is3900mg/L,OPD is2000mg/L simulated wastewater, when the Zn2+dosage is1.8g/L (300%of the theoretical reaction dosage amount), the highest COD and OPD removal efficiency are about15%. When switching to Cu2+dosage1.8g/L (300%of the theoretical reaction dosage amount), the highest COD and OPD removal efficiency are about18%.Fe3+/H2O2oxidation is excellent to OPD removal efficiency. To COD is3900mg/L,OPD is2000mg/L simulated wastewater, when the Fe3+dosage of4.0g/L, COD and OPD removal efficiency can reach90%. In order to reduce the dosage of Fe3+and improve the economy, when the Fe3+dosage of2.5g/L, further switching to H2O2dosage of0.45g/L, COD and OPD removal efficiency can also reach90%. To COD is about15000mg/L,OPD is about1100mg/L carbendazim wastewater, When dosing2.5g/L Fe3+react20min, further adding1gL H2O2, COD and OPD removal efficiency can respectively reach38%,90%.By infrared spectroscopy, elemental analysis, mass spectrometry analysis of the precipitate of Fe3+oxidize o-phenylenediamine, where in the precipitate of the C, H, N atomic ratio of6:5:2and a molecular weight of210, consistent with the2,3-diaminophenazine of C, H, N atomic ratio and the molecular weight. Thereby determined the product is2,3-diamino phenazine.By the above experimental results, it can be seen that Fe3+/H2O2oxidation has a excellent OPD removal efficiency and the process is simple, easy to operate, low cost, has practical value and economic benefits in practical application.