Fe_3O_4@沙棘枝炭吸附去除强力霉素及其非均相Fenton氧化再生  

Doxycycline Adsorption with Fe_3O_4@Seabuckthorn Carbon and Adsorbents Regeneration under Heterogeneous Fenton Oxidation

作　　者：张霞[1] 白波[2] 丁晨旭[2] 王洪伦[2] 索有瑞[2] 

机构地区：[1]长安大学环境科学与工程学院,陕西西安710054 [2]中国科学院西北高原生物研究所,青海西宁810001

出　　处：《高校化学工程学报》2015年第5期1179-1185,共7页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金项目(21176031);陕西省自然科学基金项目(2011JM2011);中国博士后特别资助项目(201104615);中央高校基本科研业务费专项资金项目(2013G2291015)

摘　　要：废弃沙棘枝条经浸渍Fe3+,在500℃下热裂解制备了Fe3O4@沙棘枝炭复合吸附剂。SEM和EDS结果表明纳米Fe3O4颗粒粒径约为40 nm,在炭表面呈孤岛状、单层、单分散覆盖。XRD表明生成的纳米Fe3O4为面心立方晶型,沙棘枝炭为无定形。以强力霉素废水为处理对象,吸附剂在碱性条件下(p H=10)表现出较好的吸附能力,吸附量随着时间的延长而增加,并且在3.0 h之后达到平衡。吸附过程遵循准二级动力学方程,相关系数R2在0.99以上。吸附等温线较好地符合Freundlich等温模型,其拟合度为0.934,明显优于Langmuir模型。ΔG0<0且ΔH0>0,说明吸附是自发吸热过程。ΔS0>0表明吸附过程不可逆。添加质量浓度为6%的H2O2,Fe3O4@沙棘枝炭复合吸附剂可经过非均相Fenton反应实现原位再生,二次使用时强力霉素吸附效率下降19.1%。Fe3O4@seabuckthorn carbon was prepared by impregnating seabuckthorn branches with Fe3＋ and then thermal cracked under 500℃. SEM and EDS results showed that the Fe3O4 nanoparticles prepared had a size of ~ 40 nm, which were discretely distributed on the carbon surface. Moreover, XRD results indicated that the Fe3O4 nanoparticles were under face-centered cubic crystal structure, while the seabuckthorn carbon was amorphous. The prepared Fe3O4@seabuckthorn carbon was used as adsorbents to treat doxycycline-containing wastewater and the results showed that this adsorbent had high adsorption capacity under alkaline conditions（p H=10）, and the adsorption capacity increased first and reached equilibrium after 3.0 h. Furthermore, the results showed that the adsorption followed pseudo-second-order kinetics with correlation coefficient R2 0.99, and the adsorption isotherms can be fitted better by Freundlich equation than Langmuir equation. Thermodynamic results（ΔG00 and ΔH00） indicated the adsorption process was spontaneous and endothermic, and ΔS00 meant it was irreversible. The adsorbents can be regenerated in-situ by heterogeneous Fenton reaction with 6%（wt） H2O2, and doxycycline removal efficiency declined by 19.1% after regeneration.

关 键 词：四氧化三铁 沙棘枝炭 强力霉素 非均相FENTON 再生 

分 类 号：X703.1[环境科学与工程—环境工程]