LIU Zhao,XU Xiang-qian,WANG Si-bin,et al.Combination of Chlorine-containing Pre-oxidants and Carbon Materials to Remove High Concentration of Manganese from Drinking Water Source:Synergistic Effect and Mechanism[J].China Water & Wastewater,2021,37(21 21):19-25.
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Combination of Chlorine-containing Pre-oxidants and Carbon Materials to Remove High Concentration of Manganese from Drinking Water Source:Synergistic Effect and Mechanism

China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU] volume: 第37卷 Number: 21 21 Page: 19-25 Column: Date of publication: 2021-11-01
Author(s):
LIU Zhao1; 2; XU Xiang-qian1; 2; WANG Si-bin1; 2; WEN Gang1; 2
(1. Key Laboratory of Northwest Water Resource, Environment and Ecology, Xi’an University of Architecture and Technology, Xi’an 710055, China； 2. Shaanxi Key Laboratory of Environmental Engineering, Xi’an University of Architecture and Technology, Xi’an 710055, China)
Keywords:
water treatment; manganese removal; chlorine-containing pre-oxidant; carbon material
Abstract:
Three kinds of chlorine-containing pre-oxidants, chlorine (Cl2), chloramine (NH2Cl) and chlorine dioxide (ClO2) and two kinds of carbon materials, namely powdered activated carbon (PAC) and carbon nanotubes (CNT)，were combined to study the effect and mechanism of removing high concentration of manganese from drinking water, and explore the manganese removal effect of effective oxidation system under different initial concentrations of manganese ions and actual water conditions.The results showed that only the combined system of chlorine and carbon materials had catalytic oxidation ability and PAC showed better catalytic effect than CNT. The removal efficiency of Mn(Ⅱ) could meet drinking water standards with 4 mg/L Cl2 combined 10 mg/L PAC or CNT reaction respectively for 10 minutes and 50 minutes.Various combinations of chloramine, chlorine dioxide and carbon materials did not show catalytic oxidation effect.Carbon materials accelerated electron transfer through adsorption, complexation and conduction, and the autocatalytic MnO2 coating formed on the surface further accelerated the oxidation of Mn(Ⅱ).Under actual water conditions, the oxidation rate of Mn(Ⅱ) by chlorine combined with PAC in the effective oxidation system was slowed down due to other cations and organics’ competing for adsorption sites and oxidants. However, the removal efficiency of Mn(Ⅱ) by chlorine dioxide alone showed no difference in oxidation efficiency between actual water and deionized water.In practical, the high concentration of manganese in the raw water could be effectively removed for a relative long reaction time by adding chlorine and PAC to the inlet water of the water treatment plant, while the appropriate dose of chlorine dioxide alone was an effective control strategy for the high concentration of manganese. The two effective oxidation systems provide a technical method for the treatment of manganese-containing raw water.
Last Update: 2021-11-01