钒掺杂磁铁矿对亚甲基蓝的吸附性能研究
Adsorption of Methylene Blue onto Vanadium-Doped Magnetite

钟远红梁晓亮朱建喜何宏平 ^* 袁鹏

文摘	采用共沉淀硝酸盐氧化法合成了不同掺杂量的钒掺杂磁铁矿(Fe_(3-x)V_xO_4, x<0.4), 并运用化学分析、X射线衍射 (XRD)、BET比表面积测试、傅立叶变换红外光谱(FTIR)以及N_2和空气气氛下的热重-差示扫描量热分析(TG-DSC)等手段对合成的Fe_(3-x)V_xO_4进行了结构表征.结果显示, 合成的Fe_(3-x)V_xO_4为立方晶系尖晶石结构, 钒离子主要类质同像替换八面体位上的Fe~(3+).合成的Fe_(3-x)V_xO_4是纳米级的磁性材料, 晶粒尺寸为28~35 nm.钒掺杂作用增加了磁铁矿的表面羟基量.吸附实验结果表明, 在中性pH下, Fe_(3-x)V_xO_4对亚甲基蓝的饱和吸附量随钒掺杂量的增加明显增大, 其吸附等温线符合Langmuir方程.Fe_(3-x)V_xO_4对亚甲基蓝的吸附反应主要在前25 min内完成, 动力学曲线符合准二级动力学方程.此外, 提高溶液的pH有利于Fe_(3-x)V_xO_4对亚甲基蓝的吸附
其他语种文摘	A series of vanadium-doped magnetite(Fe_(3-x)V_xO_4, x<0.4)synthesized by an oxidation-precipitation method, were characterized using chemical analysis, X-ray diffraction(XRD), fourier transform infrared spectroscopy(FTIR), as well as thermogravimetric and differential scanning calorimetry(TG-DSC)analyses. The obtained results show that the synthetic Fe_(3-x)V_xO_4 has spinel structure while vanadium mostly replaces Fe~(3+)in the octahedral sites. The synthetic Fe_(3-x)V_xO_4is magnetic material, with crystal size ranging from 28 to 35 nm. The substitution of vanadium in the magnetite structure increases the amount of surface hydroxyls. The experimental adsorption results indicate that, in neutral pH condition, the maximum adsorption capacities of Fe_(3-x)V_xO_4 increase obviously with the increase of vanadium concentration in magnetite while the adsorption isotherm complies well with the Langmuir model. The adsorption of methylene blue(MB)on Fe_(3-x)V_xO_4can get equilibrium in the first 25 min, supporting a pseudosecond order equation. Moreover, the rise of the solution pH value results in an increase of the adsorption capability of MB on Fe_(3-x)V_xO_4
来源	环境科学 ,2010,31(6):1568-1574 【核心库】
关键词	钒掺杂磁铁矿 ; 合成 ; 表征 ; 亚甲基蓝 ; 吸附
地址	中国科学院广州地球化学研究所, 广州, 510640
语种	中文
文献类型	研究性论文
ISSN	0250-3301
学科	行业污染、废物处理与综合利用
基金	中国科学院知识创新工程重要方向项目 ; 国家自然科学基金项目 ; 国家863计划 ; 广东省自然科学基金
文献收藏号	CSCD:3933962