College of Resource and Environment, Shaanxi University of Science & Technology, Xi'an 710021, PR China; School of Environment, Tsinghua University, Beijing 100084, China.
College of Resource and Environment, Shaanxi University of Science & Technology, Xi'an 710021, PR China.
J Colloid Interface Sci. 2014 Sep 15;430:140-6. doi: 10.1016/j.jcis.2014.05.046. Epub 2014 Jun 2.
Magnetically separable polyaniline (Fe3O4@SiO2-PANI) was prepared by in situ chemical polymerization of aniline on the surface of silica-coated Fe3O4 nanoparticles, and characterized by FTIR spectroscopy, powder X-ray diffraction, elemental analysis, transmission electron microscopy, vibrating sample magnetometry and X-ray photoelectron spectroscopy. Characterization results showed that Fe3O4@SiO2-PANI with amino groups of 1.78 mmol/g and the average diameter of 21.6 nm are superparamagnetic. Adsorption behavior of Fe3O4@SiO2-PANI nanoparticles for humic acid (HA) was investigated by batch experiments and adsorption kinetic tests. HA adsorption amount on the adsorbent decreased with increasing solution pH and the presence of Ca(2+) resulted in the enhanced HA adsorption. HA adsorption on Fe3O4@SiO2-PANI could be well described by Langmuir model and the maximum adsorption amount of the adsorbent for HA at 25°C was 36.36 mg/g. HA adsorption process on the adsorbent obey pseudo-second-order kinetics and the adsorption rates decrease with increasing initial HA concentration. The XPS analysis verified that HA adsorption over the adsorbent could be attributed to the surface complexation between the disassociated HA molecules and the protonated nitrogen of polyaniline on the adsorbent. HA loaded adsorbent could be magnetically separated and easily desorbed in 0.01 mol/L NaOH solution. Regeneration tests indicated that Fe3O4@SiO2-PANI could be used repeatedly.
通过在二氧化硅包覆的四氧化三铁纳米粒子表面原位聚合苯胺，制备了可磁化分离的聚苯胺（Fe3O4@SiO2-PANI），并通过傅里叶变换红外光谱、粉末 X 射线衍射、元素分析、透射电子显微镜、振动样品磁强计和 X 射线光电子能谱进行了表征。表征结果表明，具有 1.78mmol/g 氨基和平均直径为 21.6nm 的 Fe3O4@SiO2-PANI 是超顺磁性的。通过批量实验和吸附动力学测试研究了 Fe3O4@SiO2-PANI 纳米粒子对腐殖酸（HA）的吸附行为。吸附剂上 HA 的吸附量随溶液 pH 的增加而降低，Ca(2+)的存在导致 HA 的吸附增强。HA 在 Fe3O4@SiO2-PANI 上的吸附可以很好地用朗缪尔模型描述，该吸附剂在 25°C 下对 HA 的最大吸附量为 36.36mg/g。HA 在吸附剂上的吸附过程符合拟二级动力学，吸附速率随初始 HA 浓度的增加而降低。XPS 分析证实，HA 吸附在吸附剂上归因于解吸的 HA 分子与吸附剂上聚苯胺质子化氮之间的表面络合。负载 HA 的吸附剂可以通过磁场分离，并且可以在 0.01mol/L 的 NaOH 溶液中很容易解吸。再生实验表明，Fe3O4@SiO2-PANI 可以重复使用。
Zotero 插件