柱撑膨润土负载纳米磁性Fe_3O_4复合材料的制备及表征

SYNTHESIS AND CHARACTERIZATION OF PILLARED BENTONITE SUPPORTED Fe_3O_4 MAGNETIC NANOPARTICLES COMPOSITE MATERIAL

采用原位共沉淀法在Al-Fe柱撑膨润土上负载纳米磁性Fe3O4,制备出Fe3O4/柱撑膨润土复合材料。采用X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、拉曼光谱(Raman)、扫描电子显微镜(SEM)对样品进行表征,并且研究了其作为非均相类Fenton催化剂降解橙黄II的催化活性。结果表明:纳米Fe3O4以化学键均匀分布在膨润土表面,减少了Fe3O4的团聚。在40℃,pH为3.0,催化剂用量为1.0 g/L,H2O2初始浓度为10 mmol/L的条件下,该复合材料对橙黄II降解的拟一级反应速率常数为0.061 min-1,分别是纯Fe3O4和柱撑膨润土的4倍和3倍,柱撑膨润土与Fe3O4间存在协同催化作用,纳米Fe3O4最佳负载量为50%。

A composite material( Fe3O4/PBent) with Al-Fe pillared bentonite supported Fe3O4 magnetic nanoparticles was successfully prepared by in situ co-precipitation method and characterized by XRD,FTIR,Raman and SEM. The results showed that the Fe3O4 nanoparticles exist on the surface of bentonite by chemical bond,with better dispersing and less coaggregation. When Fe3O4/PBent was used as a heterogeneous Fenton-like catalyst to degrade Orange II,the apparent rate constant for the Orange II degradation at 40 ℃ and pH 3. 0,in the present of 1. 0 g /L catalyst and 10 mmol /L H2O2,was evaluated to be 0. 061 min- 1,equal to 4 times of Fe3O4 and 3 times of Al-Fe pillared bentonite under similar conditions.There was a concerted catalysis effect between Fe3O4 and Al-Fe pillared bentonite. The best mass ratio of Fe3O4 and pillared bentonite in the composite material was 1∶ 1 under the certain experiment condition.