【摘要】 常见阴阳离子对重金属在黄河包头段相对清洁河段表层沉积物中的吸附影响研究结果表明,不同的环境离子浓度范围内,起主导作用的影响机制不同,黄河包头段水环境中Na+、Mg2+和Ca2+对Zn2+的吸附影响较大,K+对Cu2+、Pb2+、Zn2+和Cd2+吸附影响均较大,Cl-、SO42-对Cu2+、Pb2+、Zn2+和Cd2+的吸附影响均较小,而HCO3-对Pb2+的影响较小,对Cu2+、Zn2+、Cd2+的吸附影响较大。更多还原

【Abstract】 Taking the surface sediments from the clear reach in Baotou section of the Huanghe(Yellow) River as the adsorbent,the heavy metal adsorption mechanism and affecting factor caused by ions of natural water on particulate was studied in this paper.According to the results obtained from the experiment,the affecting mechanism of heavy metal adsorption on particulate can be as follows:(1) the adsorption and disadsorpiton capacities of the heavy metal increased with the increasing of the ionic strength which caused the compress of electric double layer on mineral and reduced activity of heavy metal.As a result,there always is re-equilibrium between adsorption and disadsorption;(2) the additive cations have the competitive adsorption to the heavy metals when the cations and the heavy metals have the similar structure or physicochemical properties;(3) the heavy metal complexations caused by the anion lead to decreasing of the ionic activity and the valence state of the heavy metals,and effect on physical adsorption of the heavy metals caused by electrostatic pull.Generally,in slight acidic environment,the mineral with positive charge will adsorb the anion,and then cause the increasing of the adsorption of the heavy metals by complexations with the anion.As an important conclusion,the heavy metals into the water are affected by different adsorption and disadsorption mechanisms,and there are different dominant mechanisms in different ion concentration ranges.更多还原