磁性氧化石墨处理乳化含油废水及磁致增强效应

Treatment of emulsified oily wastewater by magnetic graphite oxide and magneto-induced enhanced effect

以高铁酸钾为氧化剂,基于改进Hummers法制备了新型磁性氧化石墨材料,在SEM、FTIR、氮气吸脱附和表面接触角表征基础上,探究了该材料处理乳化含油废水的效果及磁致增强效应.结果表明:相较于石墨,磁性氧化石墨比表面积增大,表面有卷曲结构并负载着Fe3O4颗粒,具有含氧官能团,存在疏水性较强的微观孔隙结构.在外加磁场条件下,磁性氧化石墨团聚,形成疏水性宏观孔隙结构,利于乳化油滴的吸附和附着.磁性氧化石墨处理乳化含油废水的能力远好于石墨与粉末活性炭,且处理效率与磁场强度成正相关,COD去除率可达95%以上.使用后的磁性氧化石墨进行溶剂萃取或热处理,可以循环使用.磁性氧化石墨经过4次循环使用,热再生效率为92%,溶剂萃取再生效率为86%.以上研究为乳化含油废水的处理提供了一种有效的方法.

Magnetic graphite oxide,a new type of material,was prepared by using potassium ferrate as an oxidant based on modified Hummers method.Based on SEM,FTIR,N2 adsorption-desorption and surface contact angle measurements,the decontamination and magneto-induced enhanced effect of magnetic graphite oxide on the treatment of emulsified oily wastewater were investigated.The results showed that compared with graphite,specific surface areas of magnetic graphite oxide increased and the surface exhibited curly structure loaded with Fe3O4 particles,with oxygen-containing functional groups and strong hydrophobic micro-pore structures.In external magnetic field,magnetic graphite oxide agglomerated to form hydrophobic macroscopic pore structures,which were beneficial to adsorption and adhesion of emulsified oil droplets.As expected,magnetic graphite oxide was found to be much more effective to treat emulsified oily wastewater than graphite and powdered activated carbon.The efficiency of emulsified oily wastewater treatment was positive relevance to the magnetic field strength and removal of COD could exceed 95%.The used magnetic graphite oxide could be recycled by solvent extraction or heat treatment.The regeneration efficiencies were 92% and 86% for thermal treatment and solvent extraction for 4cycles.Therefore,the research above supports an effective method for the treatment of emulsified oily wastewater.