【摘要】 钠基膨润土与羟基铁溶液反应,经过焙烧,制得性能良好的纳米复合型催化剂,结合比表面孔隙分析(BET)、X射线衍射谱(XRD)和高分辨扫描电镜(HRTEM)对催化剂的比表面积、晶相和粒度进行表征。用光度法对该催化剂降解染料罗丹明B进行了研究,详细考察了溶液起始pH值、H2O2浓度、催化剂用量和起始浓度对降解的影响以及催化剂的可重复使用性,紫外-可见光谱对降解过程进行跟踪检测,并对复相光助Fenton过程与均相光助Fenton过程进行了比较。结果表明,复合型催化剂具有很高的比表面积,铁以高催化活性的-αFe2O3存在于复合催化剂中;在pH 3.0,催化剂浓度为0.3 g.L-1,H2O2浓度为10 mmol.L-1实验条件下,100 mL 2.5×10-5mol.L-1罗丹明B,紫外光照射4 h后,紫外-可见光谱显示罗丹明B的特征峰消失,其脱色率和CODCr去除率分别为97%和71%,对该催化剂进行处理后,可以重复使用,复相光降解率要远大于均相光降解率。更多还原

【Abstract】 The iron oxide/bentonite was prepared through a reaction of a solution of OH-Fe salt with bentonite clay dispersion.BET,XRD and HRTEM were used to study its surface area,microstructure,and average particle size.The iron oxide/bentonite nano composite was developed as the heterogeneous catalyst for successful discoloration and mineralization of dye rhodamine B.And the effects of solution pH,H₂O₂ molar concentration,catalyst loading and initial rhodamine B concentration were studied in detail by photometric method.The process of degradation was traced by UV-Visible spectrum.Besides,the comparison between the heterogeneous photo-Fenton process and homogeneous photo-Fenton process was performed.The result shows that,it has large surface area and mainly consists of high catalytic activity α-Fe₂O₃.The discoloration ratio is up to 97% and the COD_Cr removal ratio is 71% after 4 h in the presence of pH 3.0,2.5×10^-5 mol·L^-1 rhodamine B 100 mL,0.3 g·L^-1 catalyst,10 mmol·L^-1 H₂O₂ and UV.The rhodamine B degradating speed of heterogeneous photo-Fenton process is much faster than that of homogeneous photo-Fenton process.The catalyst can be reused after being treated.更多还原