泰州市典型土层重金属吸附试验研究

Experimental study on heavy metal adsorption in typical soil layers of Taizhou City

城市发展过程中,重金属会从地表往地下深处迁移,不同土体对重金属离子的吸附作用不同。通过动态吸附试验和等温吸附试验,以重金属离子为对象,研究泰州市典型粉质黏土和细砂对Cu^(2+)、Zn^(2+)、Ni^(2+)的吸附特性。研究结果表明:粉质黏土和细砂对Cu^(2+)、Zn^(2+)、Ni^(2+)的吸附平衡点位于35 h处,粉质黏土对于Cu^(2+)、Zn^(2+)、Ni^(2+)的吸附能力大于细砂,两者的等温吸附曲线较为符合Freundich吸附型和线型,重金属离子浓度的增加会降低粉质黏土和细砂的吸附率。粉质黏土和细砂对重金属离子的等温吸附效率的顺序为:Ni^(2+)>Cu^(2+)>Zn^(2+)。

During urban development,heavy metals will migrate from the surface to deep underground.Different soils have dif-ferent adsorption effects on heavy metal ions.The adsorption characteristics of typically silty clay and fine sand in Taizhou City for Cu^(2+),Zn^(2+),and Ni^(2+)were studied through dynamic adsorption tests and isothermal adsorption tests.The results show that the ad-sorption equilibrium point of Cu^(2+),Zn^(2+),and Ni^(2+)on silty clay and fine sand was located at 35 h.The adsorption capacity of silty clay for Cu^(2+),Zn^(2+),and Ni^(2+)was greater than that of fine sand.The isothermal adsorption curves of silty clay and fine sand were more consistent with the Freundich adsorption type and linear pattern.Increasing the concentration of heavy metal ions reduced the adsorption rate of silty clay and fine sand.The order of isothermal adsorption efficiency of heavy metal ions on silty clay and fine sand was Ni^(2+)>Cu^(2+)>Zn^(2+)。