摘要
在本文中,研究了3种土壤粒径(2-0 mm、2-0.25 mm和0.25-0 mm)对镉的吸附-解吸行为,评估了镉在水稻土中的环境风险,通过Allometric1和Logistic模型拟合了输入浓度与水稻土吸附量之间、吸附量与解吸量之间的关系,探究了原状土吸附和解吸测定值与质量比公式拟合计算值之间的关系.研究结果表明,(1)水稻土对镉的吸附动力学更符合准二级动力学方程;(2)吸附-解吸行为更切合logistic增长;(3)等温吸附用Langmuir方程来拟合,其相关性达到显著水平(R2=0.941-0.978);(4)2-0.25 mm、0.25-0 mm及两者组合计算值可用来反馈2-0 mm的吸附解吸趋势,组间相关性达到显著(P<0.05)水平(R2=0.893-0.994);(5)测定值与公式计算值:解吸量在大多数浓度条件下组间不存在显著差异,吸附量相对低浓度条件下不存在显著差异,吸附量高浓度条件下组间显著相关,综上发现质量比公式用于原状水稻土吸附-解吸定量分析/拟合具有相对较高的可研价值.
In this article,we studied the adsorption-desorption behaviors of three soil particle sizes(2—0 mm,2—0.25 mm and 0.25—0 mm)for cadmium,evaluated the environmental risk of cadmium in paddy soil,fitted the relationship between the input concentration and the paddy soil′s adsorption capacity,between the adsorption capacity and the desorption capacity with Allometric1 and Logistic models,investigated the relationship between the measured adsorption capacity and the desorption capacity of undisturbed soil and calculated value by mass ratio formula fitting.The study results showed that(1)the adsorption kinetics of paddy soil for cadmium better suits for quasi-second-order kinetics,(2)adsorption-desorption behaviors tend to increase in a logistic way,(3)the correlation of isothermal adsorption reaches a significant level after fitted by Langmuir equation(R2=0.941—0.978),(4)the calculated adsorption capacity and desorption capacity of the soil particle size at 2—0.25 mm,0.25—0 mm and their combination could be used to display the adsorption and desorption trend of the soil particle size at 2—0 mm.The correlation between groups reached a significant(P<0.05)level(R2=0.893—0.994).(5)Measured value and formula calculation value:there was no significant difference in desorption capacity between groups under most concentration conditions and there was no significant difference between the measured value of relatively low concentration of adsorption capacity and the calculated value of formula.There was significant correlation between the measured value of high concentration of adsorption capacity and the calculated value of formula.In conclusion,it could be seen that the application of mass ratio formula to the quantitative analysis/fitting of paddy soil′s adsorption-desorption was of significant research value.
作者
任杰
刘晓文
吴颖欣
文展
李杰
张永利
刘星
REN Jie;LIU Xiaowen;WU Yingxin;WEN Zhan;LI Jie;ZHANG Yongli;LIU Xing(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou,730070,China;South China Institute of Environmental Science,Ministry of Ecology and Environment,Guangzhou,510655,China;College of Earth and Environmental Sciences Lanzhou University,Lanzhou,730000,China)
出处
《环境化学》
CAS
CSCD
北大核心
2020年第11期3200-3212,共13页
Environmental Chemistry
基金
国家重点研发计划项目(2017YFD0801300)
关键词
水稻土
镉
吸附
解吸
质量比公式
paddy soil
cadmium
adsorption
desorption
mass ratio formula
