关键词:

电絮凝, 甲基橙, 脱色, 动力学模型

Abstract:

The methyl orange (MO) simulated dye wastewater was treated by electrocoagulation. The effect of operation parameters on MO decolorization and the kinetic model of chemical oxygen demand (COD_Cr) removal were investigated. Operation parameters, such as input voltage, electrode distance, initial MO concentration, electrolyte concentration and pH, were investigated based on the decolorization efficiency of MO. Experimental results showed that up to 97% of color decay was obtained after 10 min reaction with input voltage of 20 V, current of 0.4 A, electrode distance of 2.5 cm, treated volume of 500 ml, initial MO concentration of 500 mg·L^-1, electrolyte KCl concentration of 0.5 g·L^-1 and pH of 3.0. A kinetic model for COD_Cr reduction was established based on the coagulation and oxidation processes. The experimental data fitted well with the model curves. The parameters predicted from the kinetic model showed that the coagulation process was the main pathway for COD_Cr removal and the oxidation process was the next. In addition, the increase of Fe²⁺ in the solution decreased the COD_Cr removal.

Key words:

电絮凝, 甲基橙, 脱色, 动力学模型