生物炭及其复合材料去除水体石油烃研究进展

Research Advances in Removal of Petroleum Hydrocarbons from Water by Biochar and Its Composites

水体的石油污染对生态环境造成的长期影响和破坏,是一直以来全球重点关注的环境问题之一。生物炭及其复合材料作为可有效吸附石油烃的富炭多孔材料,已成为目前水体修复领域的重要研究对象。文章对近年来生物炭及其复合材料在水体环境中石油烃吸附的相关研究进行了整理,总结了生物炭的类型、理化性质及其常见的制备过程,介绍了表面改性、磁性改性以及纳米改性等生物炭复合材料制备方式。在此基础上,简述了生物炭及其复合材料吸附石油烃时的原材料性质、污染初始浓度、外加物质以及盐度等内外因素的影响,讨论分析了去除石油烃过程中疏水相互作用、孔隙填充、π-π相互作用、毛细管效应以及表面吸附等作用机理。针对当前研究中所存在的生物炭及其复合材料的生态风险不明确、多数研究停留在实验室阶段、吸附过程机理研究不够深入等问题,提出了强化吸附材料风险评估、优化其制作工艺、提升其循环再生性能和深化吸附机理研究等方向,以期为生物炭及其复合材料吸附水体石油烃的大规模应用提供科学参考。

Oil pollution of water bodies,which has caused long-term destructively negative impact on the ecological environment,has been one of the key environmental problems concerned by the public of the world.Biochar and its composites,as carbon-rich porous materials that can effectively adsorb petroleum hydrocarbons,have become an important research object in the field of water body remediation.This paper reviewed the research advances in petroleum hydrocarbons adsorption onto biochar and its composites in water body in recent years.The types,physical and chemical properties,and the general biochar preparation methods were systematically summarized.And the preparation methods of the composites such as surface modification,magnetic modification and nano modification were described in detail.On this basis,the effects of both internal and external factors,i.e.,the raw material properties,the initial pollution concentration,the additional substance and the salinity,on the adsorption process were briefly introduced;the mechanisms of removing petroleum hydrocarbon involving the hydrophobic interaction,pore filling,π-πinteraction,capillary effect and surface adsorption in the adsorption process,were analyzed and discussed.In addition,pinpointing the problems existing in the current research,for example,the ecological risk of biochar and its composites remained yet not clear,the relevant investigation work still stayed at laboratory scale,and the mechanism of adsorption process has yet to be further explicated,comments were proposed to strengthen the risk assessment of adsorption materials,optimize their manufacturing process,improve their recycling performance and systematically examine adsorption mechanism.Hopefully,this review may provide scientific reference for the large-scale application of biochar and its composites in mitigating petroleum hydrocarbons pollution.