摘要
锑(Sb)污染是我国的典型环境问题之一,高浓度的Sb废水是Sb矿区一个重要的Sb污染来源,治理Sb矿废水的重点是高效去除水中的Sb(Ⅴ)。因此本研究采用经典吸附实验方法,用改性生物炭去除水溶液中的Sb(Ⅴ),旨在评价该改性生物炭在含Sb废水中的应用效果和潜力;结果显示,生物炭经过改性处理后吸附Sb(Ⅴ)能力显著增大,热解温度为600℃得到的改性生物炭(MC600),在投加比为2.5 g·L^−1、pH=7.5条件下,对Sb(Ⅴ)的吸附能力最强,Langmuir模型拟合的最大饱和吸附量为8089 mg·kg−1。吸附动力学实验发现Elovich方程对MC600吸附Sb(Ⅴ)的拟合效果最好(R^(2)=0.993),吸附过程主要为非均匀表面吸附;吸附等温实验中MC600对Sb(Ⅴ)的吸附行为适用于Langmuir和Langmuir-Freundlich模型拟合(R^(2)=0.981、0.980),表明MC600对Sb(Ⅴ)的吸附主要以单分子层吸附为主,并伴有部分多分子层吸附。通过对MC600吸附高浓度Sb(Ⅴ)后的样品进行解吸,2种样品3次总解吸率均低于30%,表明MC600吸附Sb(Ⅴ)的效果稳定。以上结果表明,改性的MC600对高浓度Sb废水中Sb(Ⅴ)的去除具有潜在的应用前景。
Antimony(Sb)pollution is one of the typical environmental issues in China.High concentration of Sb in wastewater is an important source of Sb pollution in Sb mining area.The key point of treating Sb mine wastewater lies in high efficient removal of Sb(Ⅴ)in wastewater.To evaluate the removal efficiency and capacity of Sb(Ⅴ)from Sb-containing wastewater by modified biochar,batch experiments were conducted in this study.The results showed that Sb(Ⅴ)adsorption performance increased for the biochar after modification.The adsorption kinetics experiment indicated that the Sb(Ⅴ)adsorption by MC600 conforms to the Elovich model(R^(2)=0.993),and the adsorption process was mainly non-uniform surface adsorption.In the adsorption isotherm experiment,the Sb(Ⅴ)adsorption behavior of MC600 was suitable for Langmuir and Langmuir-Freundlich models with respective R^(2) value of 0.981 and 0.980,which showed that the Sb(Ⅴ)adsorption on MC600 was mainly single molecular layer adsorption with partial multi-molecular layer one.The modified biochar(MC600)pyrolyzed at 600℃presented the maximum adsorption amount for Sb(Ⅴ)at the dosage of 2.5 g·L^−1 and pH=7.5.The maximum adsorption capacity determined by the Langmuir model was 8089 mg·kg−1.According to the desorption experiment,the total desorption ratios of Sb(Ⅴ)from two MC600 samples were less than 30%,which showed that Sb(Ⅴ)adsorption on MC600 was stable.This study provided an alternative way for Sb(Ⅴ)removal from Sb-rich wastewater.
作者
廖路
吴攀
王兵
李玲
韩志伟
LIAO Lu;WU Pan;WANG Bing;LI Ling;HAN Zhiwei(College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China;Key Laboratory of Karst Georesources and Environment,Ministry of Education,Guizhou University,Guiyang 550025,China;State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2021年第2期435-445,共11页
Chinese Journal of Environmental Engineering
基金
贵州省科技计划项目(黔科合支持[2019]2838号)
国家自然科学基金委员会-贵州省人民政府喀斯特科学中心项目(U1612442)
贵州省科学技术基金(黔科合基础[2020]1Z040)
国家重点研发计划项目(2018YFC1801701)。
关键词
锑污染
含锑废水
改性生物炭
吸附
解吸
antimony pollution
antimony-containing wastewater
modified biochar
adsorption
desorption
