通过泥沙颗粒表面孔隙特征分析实验与硝酸铜吸附实验,分析比较干净态泥沙与原状沙的界面作用规律,说明水环境变化下泥沙颗粒的界面作用特征。采用物理化学吸附仪分析泥沙颗粒的表面形貌特征,实验结果揭示干净态泥沙表面孔隙结构丰富,表面形貌较原状沙复杂。铜离子吸附实验结果给出干净态泥沙与原状沙的最大饱和吸附量分别为0.854与4.525 g/kg,吸附/解吸速率分别为1.511与5.652,表明了原状沙界面作用能力高于干净沙。水环境变化造成污染物在泥沙颗粒表面的吸附与聚集,改变了泥沙颗粒的表面形貌特征,而生物膜与腐殖质的存在增强了泥沙颗粒的界面作用能力,界面作用特征由物理吸附作用转变为化学吸附作用。
Interfacial interaction properties are related to the surface properties of sediment particles.Surface properties and interfacial interactions are modified with the change in water environments.Experiments of surface pore characteristics and copper adsorption were performed to analyze the interfacial interaction of cleaned sediments and the original state sediments with the change of water environments.Physical and chemical adsorption apparatus was adapted to measure surface morphology characteristics of sediment particles.The experimental results reveal that cleaned sediments have richer surface pore structures and more complex surface topography.In copper ions adsorption experiments,saturated adsorption capacities of cleaned and original sediments are 0.854g/kg,4.525g/kg,and adsorption/desorption ratios are 1.511 and 5.652,respectively.Original sediments have stronger ability of interfacial interaction than cleaned sediments.Contaminations are adsorbed to particle surfaces,which results in the change of the surface morphology of particles.Biomenbrane and humus adhered to the particles' surface enhance the interaction ability.With the change in water environments,interfacial interaction of sediment transformed from physical adsorption to chemical adsorption.