复合还原剂制备的胶态水合二氧化锰的混凝除污机制

Contaminant Removal Mechanism of Colloidal Hydrated Manganese Dioxide Produced by Composite Reducing Agent

通过烧杯混凝试验考察了以高锰酸钾与复合还原剂制备的胶态水合MnO2的除污效能;采用透射电镜观察了胶态水合MnO2凝聚粒子的形态结构,并研究了胶态水合MnO2絮凝沉淀的电荷特征及水合MnO2颗粒的红外谱图,探讨了其除污机制。结果表明:较低投量的胶态水合MnO2即表现出了优异的混凝除浊效能。该胶态水合MnO2凝聚粒子的直径约为10 nm,并具有丰富的表面羟基,其絮凝沉淀物的表面呈电负性;胶态水合MnO2的混凝除浊机制主要为吸附架桥和网捕卷扫作用,去除有机物的机制主要为粒子表面的特性吸附作用。

The contaminant removal efficiency by colloidal hydrated manganese dioxide produced by potassium permanganate and composite reducing agent was investigated by jar test. The structure and shape of colloidal hydrated manganese dioxide particle was observed by transmission electron microscope （TEM）, and the charge of its floc and the infrared （IR） characteristic of its particle were also studied. The contaminant removal mechanism was discussed. The results show that the excellent coagulation efficiency can be achieved at low dosage of colloidal hydrated manganese dioxide. The diameter of the colloidal hydrated manganese dioxide particle is about 10 nm, it has abundant surface hydroxyl, and the charge of its floc shows electronegative. The adsorption bridging and entrapping-sweeping functions are the main mechanism of coagulation, and the characteristic adsorption function of particle surface is the main mechanisms of organics removal.