附着生物膜的泥沙颗粒对磷的吸附特性研究

附着在泥沙表面的生物膜具有很强的吸附特性，对水环境中营养盐等物质的迁移转化规律具有非常重要的作用。本文采用实验手段分别对去除表面杂质的纯净泥沙和表面附着生物膜的泥沙进行吸附营养盐磷的实验研究，对比了去除生物膜的泥沙与附着生物膜的泥沙对磷的吸附能力，研究了附着生物膜的泥沙颗粒吸附磷的动力学及热力学特征。研究结果表明，去除表面杂质的纯净泥沙对磷的吸附性微小，而附着生物膜的泥沙颗粒对磷的吸附能力很强，在相同条件下附着生物膜的泥沙颗粒的吸附量比纯净泥沙吸附量高出1个数量级；同时附着生物膜的泥沙颗粒吸附磷的动力学特性符合准二级动力学模型，等温吸附特性符合Langmuir等温式，吸附速率和平衡吸附量随泥沙粒径减小而增大。

Study on Phosphorus Adsorption to the Sand Attached with Surface Coatings

Surface coatings attached to the sand have a strong adsorption and play a very important role in the migration and transformation of nutrients and other substances in the water environment. Adsorption experiments were carried out by using sand removed surface coatings and sand with surface coatings attached respectively. The adsorption ability of phosphorus to two different kinds of sand was compared. The kinetic and thermodynamic adsorption of phosphorus to the sand with surface coatings attached was studied. The results show that the sand removed surface coatings has little adsorption to phosphorus. The sand with surface coatings cultured has a strong adsorption to phosphorus, with equilibrium adsorption capacity 1 order of magnitude higher than that of sand removed surface coatings. Phosphorus adsorption by the sand with surface coatings cultured was consistent with pseudo-second order kinetic model. Isotherms fitted the Langmuir models well. Adsorption rate and equilibrium adsorption capacity increases as the sand particle size decreasing.