摘要
利用生物炭作为吸附剂处理重金属污染废水是目前的研究热点。研究结果表明生物碳处理重金属废水的效果理想,然而目前对于生物碳吸附确定重金属的机制以及生物碳的改性研究缺少系统清晰的论述。文章综述了生物碳的特性,生物碳吸附As、Pb的主要机制和改性生物碳对As、Pb的吸附行为。生物质类型的差异是生物碳性质不同的主要影响因素,此外热解温度的升高使得生物碳的p H值、比表面积、孔隙率和矿物含量整体上增加,而官能团含量却在减少。生物碳吸附As的机制主要是络合作用和静电吸附,而吸附Pb依靠络合、阳离子交换和沉淀。除了吸附机理,通过给生物碳加载矿物和纳米晶体,并用碱溶液活化可以显著增强生物碳对As、Pb的吸附能力。文章结论可以为今后生物碳固定化重金属的研究提供参考。
The biochar as a sorbent to treat metal-contaminated water has receivedincreasing attention.The study has revealed the effect is satisfactory.However, there is alack of systematically and clearly view on the sorption mechanisms of biochar for different metals and the study modification of the biochar.This review summarizes the characteristics of biochar,the main sorption mechanisms of biocharto As and Pb,and the adsorption behavior to As and Pb by modified biochar.The differences of type is the mian influencing factor of the biochar properties,and the raising of pyrolysis temperature can make the pH,specific surface area,poriness and mineral contentintegrally increase,but functional groupcontent decrease.The mechanisms of biocharto As primarily is complexation and electrostatic adsorption,and to Pb is complexation,cation exchange and sediment. Except the sorption mechanisms,by loading mineral and nanocrystal to biochar, andactivated by aqueous alkali can remarkably enhance the adsorption capacity.The conclusion can provide reference to the research of fixing the heavy metal by biochar.
出处
《大众科技》
2017年第5期49-52,共4页
Popular Science & Technology
基金
河池学院2016年硕士专业学位授予单位立项建设基金课题"广西东兰坡豪湖湿地生态系统服务功能研究"(2016HJA02)
关键词
生物炭
重金属废水
吸附机制
Biochar
As and Pb
heavy metal wastewater
the sorption mechanisms
