Enhanced removal of organics by permanganate preoxidation using tannic acid as a model compound-Role of in situ formed manganese dioxide  

作　　者：ZHANG Lizhu MA Jun LI Xin WANG Shutao 

机构地区：[1]School of Science, Harbin Institute of Technology, Harbin 150090, China [2]School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China

出　　处：《Journal of Environmental Sciences》2009年第7期872-876,共5页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China under the scheme of Inno-vation Team Fund (No. 50821002);the Natural Science Foundation of Heilongjiang Province (No. 24405433);the State Key Laboratory of Urban Water Resource and Environment under the scheme of Environmental Function Materials and Application

摘　　要：The effect of permanganate preoxidation on organic matter removal during the coagulation with aluminum chloride was investigated using tannic acid as a model compound. Results showed that a small amount of KMnO4 （0.75 mg/L） increased the removal efficiency of tannic acid up to 20%, as compared to the process of coagulation by aluminum chloride alone. The key factor enhancing the removal efficiency of tannic acid in preoxidation process was the in situ formation of a reductant manganese dioxide. The complexation model was used to describe the reaction between MnO2 and tannic acid. Under weak pH condition, tannic acid was difficult to be adsorbed by MnO2 due to the static electrical repulsive forces. The presence of Ca2＋ served as a bridge to hold the negative charged MnO2 and tannic acid together, which could be a crucial factor influencing tannic acid adsorption by in-situ manganese dioxide.The effect of permanganate preoxidation on organic matter removal during the coagulation with aluminum chloride was investigated using tannic acid as a model compound. Results showed that a small amount of KMnO4 （0.75 mg/L） increased the removal efficiency of tannic acid up to 20%, as compared to the process of coagulation by aluminum chloride alone. The key factor enhancing the removal efficiency of tannic acid in preoxidation process was the in situ formation of a reductant manganese dioxide. The complexation model was used to describe the reaction between MnO2 and tannic acid. Under weak pH condition, tannic acid was difficult to be adsorbed by MnO2 due to the static electrical repulsive forces. The presence of Ca2＋ served as a bridge to hold the negative charged MnO2 and tannic acid together, which could be a crucial factor influencing tannic acid adsorption by in-situ manganese dioxide.

关 键 词：KMNO4 MNO2 adsorption COAGULATION oxidation tannic acid 

分 类 号：TU991.2[建筑科学—市政工程] O629.8[理学—有机化学]