摘要
重金属铬的污染会严重威胁到土壤和水体的环境安全,而水中的六价铬化合物则具有很强的迁移性、富集性和氧化性等特性,更具有危害性且难以处理。吸附法是一种能简单、高效地处理含重金属污水的处理技术。在磁力搅拌条件下采用花生壳生物炭分别与高岭土和膨润土混合制备而成两种生物炭–黏土材料,并分别对这两种生物炭–黏土的表面特性进行表征。结果发现所选用的两种黏土均能不规则地负载在生物炭的表面。吸附实验结果显示,生物炭–高岭土(Biochar@Kaolin)吸附铬(Ⅵ)的能力显著高于生物炭–膨润土(Biochar@Bentonite)。从吸附动力学方程的分析可以看出,合成的两种生物炭负载黏土吸附水中的铬(Ⅵ)均符合伪二级动力学方程。从吸附等温线分析中可以得到,Biochar@Bentonite吸附铬(Ⅵ)的过程符合Langmuir模型,而Biochar@Kaolin吸附铬(Ⅵ)的过程符合Freundlich模型。研究结果显示,采用生物炭–黏土的复合材料修复环境中的重金属污染具有广阔的应用前景。
Heavy metal chromium pollution seriously threatens the environmental safety of soil and water body. The Cr(Ⅵ) compound has strong migration ability, enrichment and strong oxidizing ability. These properties make Cr(Ⅵ) ions more dangerous and difficult to handle. Adsorption technology is a simple and effective method for treatment of heavy metal pollution. The two clay-biochars are made by mixing biochar derived from peanut shell and two kinds of clays(Kaolin and bentonite) under magnetic stirring conditions. A variety of characterizations suggest that clays uniformly deposit on the surface of biochar. Adsorption experiments indicate that the sorption of Cr(Ⅵ) ions from wastewater on Kaolin-biochar is significantly higher than that of bentonite-biochar. Adsorption kinetic of Cr(Ⅵ) on two clay-biochars follows satisfactorily the pseudo-second order model due to high correlation coefficient(R2>0.999). Adsorption isotherms of Cr(Ⅵ) on Biochar@Bentonite are fitted by Langmuir model, whereas the Freundlich model fits better the Cr(Ⅵ) sorption on Biochar@Kaolin. These findings are crucial for the potential application of clay-biochar composites for the treatment of the immobilization of heavy metals in environmental remediation.
作者
王海
阳柠灿
邱木清
WANG Hai;YANG Ningcan;QIU Muqing(School of Life Science,Shaoxing University,Shaoxing 312000,China)
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2020年第3期301-308,共8页
Journal of Inorganic Materials
基金
National Natural Science Foundation of China(21876115)
Public Welfare Program of Zhejiang Natural Science(LGF19C030001)。
