[Cu adsorption by phaeozem and burazem].
Studies on the thermodynamics and kinetics of copper (Cu2+) adsorption by phaeozem and burozem showed that that the adsorption of Cu2+ by these two soils was increased with the increasing concentration of Cu2+ within the range of Cu2+ concentrations used in the experiment, but the amount of Cu2+ adsorbed and fixed on phaeozem was much higher than that on burozem. When the test Cu2+ concentration in adsorption equilibrium was 95 mg.kg-1, its adsorption by burozem was nearly 3720 mg.kg-1, whereas by phaeozem was as high as 6076 mg.kg-1. Under the highest CuCl2 treatment of 400 mg.kg-1, Cu2+ adsorbed by phaeozem and burozem was 6159.0 mg.kg-1 and 4736.6 mg.kg-1, respectively. The adsorption of Cu2+ by the test soils could significantly conform to the Freundlich and Temkin equation, while Langmuir equation was not applicable to describe the isothermal adsorption processes of Cu2+ by the two soils. The adsorption of Cu2+ by the test soils was very rapid, which could reach its balance after 15-20 min. The adsorption within the first 2 min at its beginning stage accounted for 90% of the Cu equilibrium adsorption. The adsorptive rate of Cu2+ by phaeozem was decreased more quickly than that by burozem with the time. The two-constant equation was the optimal model to describe the adsorption of Cu2+. The other models in point were first-order dynamic equations and Elovich equations, whereas parabolic diffusion equations were not suitable ones.
Yu
Ying
Y
Key Laboratory of Terrestrial Ecological Process, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. yyuhelen@hotmail.com
Zhou
Qixing
Q
Wang
Xin
X
Ren
Liping
L
D000327:Adsorption; D003300:Copper / Q000737:chemistry*; D007700:Kinetics; D012987:Soil / Q000032:analysis*; D013816:Thermodynamics
D012987:Soil; D003300:Copper