摘要
采用一次平衡法研究吸附态Cu2 + 在黑土和棕壤上的解吸行为并进行了比较 .结果表明 ,与棕壤相比 ,黑土吸附态Cu2 +解吸有更长的滞后阶段 ,黑土在Cu2 + 的吸附量低于 72 9 0 0mg·kg-1(Cu2 + 处理浓度小于 4 0mg·L-1) ,棕壤在Cu2 + 的吸附量低于 393 2 9mg·kg-1(Cu2 + 处理浓度小于 2 0mg·L-1)时 ,土壤吸附态Cu2 + 几乎不发生解吸 .2种土壤吸附态Cu2 + 的解吸率均较低 ,尤其是黑土 .在试验所采用的Cu2 + 处理浓度范围内 ,黑土与棕壤吸附态Cu2 + 的最高解吸率分别为 6 6 0 %和13 5 6 % .Freundlich方程为描述 2种土壤Cu2 + 等温解吸过程的最佳方程 .黑土和棕壤吸附态Cu2 + 的解吸速率均较快 ,在4 0min左右基本达到平衡 .描述黑土和棕壤解吸动力学过程的最优模型为双常数速率方程 ,其次为Elovich方程 .
Desorptive behavior of Cu 2 from phaeozem and burozem was studied and compared using the batch method. The results indicated that Cu 2 desorbed from phaeozem tested had a longer lag period than that from burozem. When adsorbed Cu 2 for phaeozem was lower than 729.00 mg·kg -1 (Cu 2 concentration was lower than 40 mg·L -1), and on burozem was lower than 393.29 mg·kg -1 (Cu 2 concentration was lower than 20 mg·L -1), adsorbed Cu 2 was hardly desorbed. Meanwhile, the desorption ratio of Cu 2 from the two soils were both low, especially for phaeozem. In the range of Cu 2 concentration used in the experiments, the desorption rate maximums of Cu 2 for phaeozem and burozem were respectively 6.60% and 13.56%. Freundlich equation could best describe desorption isotherm processes of Cu 2 from the two soils. Adsorbed Cu 2 on soils was desorbed so fast from phaeozem and burozem that the desorption equilibrium could be reached only after 40 min desorption. The best model to describe Cu 2 desorption kinetics was two-constant equations, followed by the Elovich equation.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2004年第1期128-132,共5页
Environmental Science
基金
国家杰出青年科学基金项目(20225722)
国家重点基础研究发展规划项目(G1999011808)
中国科学院知识创新重要方向项目(KZCX2SW416)
关键词
Cu^2^+解吸
热力学
动力学
黑土
棕壤
Cu 2
desorption
thermodynamic process
kinetic process
phaeozem
burozem