摘要
沉积物悬浮颗粒对重金属吸附是重金属在湖泊中迁移的关键环节,受到多种环境条件的影响.为了探究溶解性有机质(dissolved organic matter,DOM)对沉积物悬浮颗粒吸附Cu(Ⅱ)的影响及作用机制,通过室内模拟沉积物悬浮液进行Cu(Ⅱ)吸附试验.结果表明,两种DOM(富里酸和沉积物DOM)不同程度地促进了Cu(Ⅱ)在悬浮颗粒上的吸附;吸附48 h后,吸附百分比从71.51%分别提高到了75.31%和85.69%.扫描电子显微镜-能谱结果显示,在DOM的影响下,Cu(Ⅱ)被吸附后存在于沉积物颗粒内部.紫外-可见光谱技术分析结果表明,在吸附反应过程中,Cu(Ⅱ)与DOM存在先络合后解离的过程.荧光激发发射矩阵结合平行因子分析、同步荧光光谱结合二维相关分析的结果表明,类蛋白组分能够促进Cu(Ⅱ)在沉积物悬浮颗粒上的吸附,其中类酪氨酸组分在促进Cu(Ⅱ)被沉积物颗粒吸附沉淀过程中优先发挥作用,而类腐殖酸组分几乎没有促进吸附作用.完善了湖泊重金属迁移的相关理论,为沉积物重金属污染防治提供了一定的依据.
The adsorption of heavy metals by suspended sediment particles is a key process in the migration of heavy metals in lakes and is affected by various environmental conditions.To reveal the effects and mechanisms of dissolved organic matter(DOM) on the adsorption of copper ions by suspended sediment particles,a Cu(Ⅱ) adsorption test was conducted through a laboratory simulation test.The results showed that DOM promoted the adsorption of Cu(Ⅱ) onto the suspended particles.Under the respective influences of fulvic acid and DOM extracted from the sediment of the Xiangjiang River,the adsorption percentage of Cu(Ⅱ) increased from71.51% to 75.31% and 85.69%.Scanning electron microscope-energy spectroscopy results showed that under the influence of DOM,Cu(Ⅱ) existed inside the sediment particles after being adsorbed.The results of UV-visible(UV-Vis) spectroscopy showed that Cu(Ⅱ) and DOM were first complexed and then dissociated during the adsorption reaction.The results of fluorescent excitationemission matrix spectroscopy combined with parallel factor analysis and synchronous fluorescence spectroscopy combined with two-dimensional correlation analysis indicate that protein-like components promoted the adsorption of Cu(Ⅱ) onto the sediment suspended particles.In particular,tyrosine-like components played a critical role in promoting adsorption.However,humic-like components hardly promote this adsorption.This study has improved the theory of heavy metal migration in lakes and can be used as a basis for the prevention and control of heavy metal pollution in sediments.
作者
丁翔
李忠武
徐卫华
黄梅
文佳骏
金昌盛
周咪
陈佳
DING Xiang;LI Zhong-wu;XU Wei-hua;HUANG Mei;WEN Jia-jun;JIN Chang-sheng;ZHOU Mi;CHEN Jia(College of Environmental Science and Engineering,Hunan University,Changsha 410082,China;College of Resources and Environmental Sciences,Hunan Normal University,Changsha 410081,China)
出处
《环境科学》
EI
CAS
CSCD
北大核心
2021年第8期3837-3846,共10页
Environmental Science
基金
国家自然科学基金项目(51879103)
湖南省科技发展重点项目(2017SK2351)
湖南省科技创新计划项目(2018SK2047)。
关键词
溶解性有机质(DOM)
沉积物悬浮颗粒
铜离子
吸附
平行因子分析
二维相关分析
dissolved organic matter(DOM)
suspended sediment particle
copper ions
absorption
parallel factor analysis
two-dimensional correlation analysis
