摘要
为了探究Pb在底泥和土壤中的吸附行为,通过OECD guideline 106平衡吸附法,来探讨Pb在底泥和土壤中的吸附特性以及不同pH、有机质和N、P含量对Pb吸附特性的影响。结果表明：Temkin模型能够更好地拟合底泥对Pb的吸附,R2=0.925;Freundlich模型能够更好地拟合土壤对Pb的吸附,r=0.971。Pb在15,25,35℃下吸附条件下,温度升高会促进底泥和土壤对Pb的吸附,ΔG〈0,ΔH〉0,说明底泥和土壤对Pb的吸附为自发的吸热反应;在pH为3~11的条件下,Pb的吸附量随pH的升高呈现出先升高后逐渐趋于平缓的趋势,当pH=5时吸附效果最好。去除有机质后,底泥和土壤对Pb的吸附量减少,分别减少了121.6,87.4mg/kg。随着溶液中N、P浓度的增加底泥和土壤对Pb的吸附量逐渐减小,推断是因为N、P加入时携带加入K＋,K＋与Pb产生了竞争吸附导致Pb的吸附量的降低。
In order to study the adsorption behavior of Pb in sediment and soil,the adsorption of Pb adsorption in sediment and soil were investigated by batch equilibrium studies according to OECD guideline 106,and the influence of the pH,organic matter and N,P concentration on adsorption process were also discussed in this study.The results showed that the adsorption isotherm of Pb was well fitted with the Temkin equation in the sediment,the correlation constant R2 was 0.925;the adsorption isotherm of Pb was well fitted with the Freundlich equation in the soil,the correlation constant R2 was 0.971.Studies showed that,Pb under the adsorption condition of 15,25 and 35℃,with the increase of temperature,the adsorption of Pb in sediment and soil would be strengthened,ΔG0,ΔH0,revealed that the adsorption of Pb in the sediment and soil was a spontaneously endothermic process.Studies showed that,under the pH condition of 3~11,the Pb adsorption quantity increased with the increase of pH,after the first increased and then to be gentled.When the pH was equal to 5,the adsorption effect was best.After removal of the organic matter the adsorption amount of Pb in sediment and soil decreased by 121.6,87.4mg/kg,respectively.With the increase of N,P,the adsorption amount of Pb in sediment and soil decreased,which might be due to with the carrying of N,P,the K＋was added,and it had a competitive adsorption of Pb led to reducing adsorption capacity of Pb.
出处
《水土保持学报》
CSCD
北大核心
2016年第5期255-260,265,共7页
Journal of Soil and Water Conservation
基金
吉林省科技厅重大科技攻关专项(20130204054SF)
吉教科合字【2014】第467号
关键词
底泥
PB
吸附
PH
有机质
氮和磷
sediment
Pb
adsorption
pH
organic matter
N and P
