摘要
为了解重金属在土壤中的迁移转化规律,为确定土壤环境容量和治理土壤重金属污染提供理论依据,采用室内试验方法研究了采自山东的棕壤、黑龙江的黑土、陕西的黄棕壤和山西的褐土吸附Cu2+、Pb2+和Cd2+的特性及溶液pH、外加腐殖酸、溶液中重金属初始含量对吸附的影响。由振荡平衡法进行吸附试验,原子吸收分光光度法测定平衡溶液中重金属的吸光度值。试验结果表明:随着溶液中Cu2+、Pb2+和Cd2+含量的增大,4种土壤对Cu2+、Pb2+和Cd2+的吸附量逐渐增大。溶液pH值对土壤吸附重金属的影响因土壤性质和重金属特性的不同而不同。加入腐殖酸,4种土壤对Cu2+、Pb2+和Cd2+的吸附量明显减少。不同吸附模型拟合结果表明,4种土壤对Pb2+的吸附等温线都符合Langmuir方程和Freundlich方程,对Cu2+吸附等温线拟合的Langmuir方程和Freundlich方程的相关性不理想,对Cd2+吸附等温线拟合符合Freundlich方程。
In order to realize the regulation of migration and conversion for heavy metals in the soils, and acquire foundation for determining the adsorptive capacity of soils and managing pollution of soils by heavy metals. Characters of cuprum, lead, cadmium in soils, which were from brown soil of Shandong, hlackland of Heilongjiang, yellow brown soil of Shanxi and Cinnamon soil of Shanxi, were studied by experiment methods in-house. Meanwhile, effect of pH value, humic acid and initial content of heavy metals in solution were also studied. Oscillation balance method was used in the adsorption experiment, and ahsorhance value of heavy metals in the balance solutions was determined by atomic absorption spectrophotometry. The results showed that along with content of Cu^2＋, Ph^2＋ and Cd^2＋ increasing, adsorption amounts increased gradually. The effect of pH value on heavy metal adsorption was different since the metal and soil characteristics were different. Adding humic acid, adsorption amounts of Cu^2＋, Ph^2＋ and Cd^2＋ in the four soils were significant reduction. The adsorption data indicated： Pb^2＋ adsorption isotherms of tested soils followed Langmuir equation and Freundlich equation. Cu^2＋ adsorption isotherms of tested soils were not fitted Langmuir equation and Freundlich equation. Freundlich equation described the adsorption behavior of Cd^2＋ in the tested soils.
出处
《生态环境》
CSCD
北大核心
2008年第1期245-248,共4页
Ecology and Environmnet
关键词
土壤
镉
铅
铜
吸附
soils
cadmium
lead
cuprum
adsorption
