引用本文:
【打印本页】   【HTML】   【下载PDF全文】   查看/发表评论  【EndNote】   【RefMan】   【BibTex】
过刊浏览    高级检索
本文已被:浏览 21次   下载   
分享到: 微信 更多
Fe3O4/BC复合材料的制备及其吸附除磷性能
胡小莲,杨林章,何世颖,冯彦房,周玉玲,等
作者单位E-mail
胡小莲 江苏省农业科学院 农业资源与环境研究所 244209207@qq.com 
杨林章 江苏省农业科学院 农业资源与环境研究所  
何世颖 江苏省农业科学院 农业资源与环境研究所  
冯彦房 江苏省农业科学院农业资源与环境研究所  
周玉玲 江苏省农业科学院 农业资源与环境研究所  
摘要:
为解决磁性吸附剂Fe3O4不稳定、易在水中团聚,吸附效率较低的问题,本研究以BC(生物炭)为载体,采用化学共沉淀法制备了Fe3O4/BC(生物炭负载的纳米四氧化三铁)复合材料,并将其应用于水体中磷酸根(PO43--P)的吸附去除。探究了Fe3O4/BC对水中磷的吸附-解析性能,考察了纳米Fe3O4负载比例、吸附体系pH和磷酸根初始浓度ρ(PO43--P)等因素对磷酸根去除率的影响,并考察了吸附机制。研究表明:所制备的Fe3O4纳米颗粒呈球形,均匀散布在生物炭表面;Fe3O4/BC复合材料能高效吸附水中的磷酸根,在pH=3,温度为25 ℃,ρ(PO43--P)为50 mg/L,Fe3O4/BC投加量为400mg(质量比Fe3O4:BC=1:1),吸附3h达到平衡后,Fe3O4/BC对磷的去除率达到92.14%。Fe3O4/BC复合材料吸附磷酸根的机制包括配位体交换和静电吸引,吸附过程较好地符合准二级动力学模型和Langmuir等温吸附方程。Fe3O4/BC具有良好的解吸附性能,用c(NaOH)为2 mol/L溶液对吸附磷酸根饱和后的Fe3O4/生物炭进行解吸附,解吸效率达到80%。Fe3O4/生物炭重复利用性好,在第四次利用后还保持75%以上的吸附效率。研究显示,Fe3O4/BC复合材料能高效吸附去除磷酸根,同时可以利用磁力方便回收,复合绿色化学原则,具有良好的应用前景。 关键字 生物炭;纳米Fe3O4;Fe3O4/生物炭;磷;去除效率
关键词:  生物炭  Fe[sub_s]3[sub_e]O[sub_s]4[sub_e]  Fe[sub_s]3[sub_e]O[sub_s]4[sub_e]/生物炭    去除效率
DOI:
分类号:
基金项目:农业部公益性行业(农业)科研专项(No.20150306);江苏省农业自主创新资金项目(CX (15) 5004);省六大人才高峰项目(NY-054)
Preparation of Fe3O4/BC Composite and Its Application for Phosphate Adsorptive Removal
huxiaolian,fengyanfang,周玉玲,et al
Abstract:
Phosphate is one of the key factors that responsible for eutrophication of surface waters, and adsorption technology is competitive to remove phosphate from aqueous solutions due to its high efficient and low cost. As is known, magnetic adsorbent such as magnetite (Fe3O4) can be easily recovered from aqueous solution by magnetic force, which will avoid adsorbate release from adsorbent surface. However, magnetite is unstable and easy to aggregate in aqueous solutions, resulting in low removal efficiency. In the present study, a nano-composite (Fe3O4/BC) was synthesized by co-precipitation method, which was to load nano- Fe3O4 onto the surface of black carbon (BC). Then Fe3O4/BC was applied to remove phosphate from wastewater. Fe3O4/BC was characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier Transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and Zeta potential. Furthermore, removal efficiency and desorption efficiency of phosphate by Fe3O4/BC was investigated .Results showed that the removal efficiency of phosphate by Fe3O4/BC was higher than that of Fe3O4. The maximum removal efficiency reached 92.14% under the following conditions: pH 3, initial phosphate concentration 50 mg/L, 400mg Fe3O4/BC (t mass ratio Fe3O4:BC=1:1) and reaction temperature of 25℃. BC as supporter improved the dispensability of Fe3O4. The removal mechanism can be explained by ligand exchange and electrostatic attraction. Fe3O4/BC was observed good adsorption capacity and could be separated fast and easily from aqueous solution by a permanent magnet. Kinetics studies showed that the adsorption process followed the pseudo-second-order kinetic model. Meanwhile, isotherm data showed that phosphate removal by Fe3O4/BC could be well described using Langmuir model. The desorption efficiency of phosphate from Fe3O4/BC reached 80% in NaOH solution (2 mol/L). Moreover, the removal efficiency of the recycled Fe3O4/BC reached 75% even during the fourth cycle. This study showeds that Fe3O4/BC could effectively remove phosphate from aqueous solutions, which was consistent with green chemistry principle and was a promising phosphate adsorbent in future application.
Key words:  BC  Fe3O4  Fe3O4/BC  Phosphate  removal efficiency