羟基铁铝柱撑膨润土异相Fenton光催化降解偶氮胭脂红B的研究

HYDROXY-IRON-ALUMINUM PILLARED BENTONITE AS A CATALYST FOR HETEROGENEOUS PHOTO-FENTON DEGRADATION OF AZOCARMINE B

采用离子交换的方法制备羟基铁铝柱撑膨润土光催化材料,并通过X射线衍射分析(XRD)和紫外-可见漫反射吸收图谱对其进行表征,同时以羟基铁铝柱撑膨润土为异相光助Fenton催化剂,在不同实验条件下,探讨了催化剂对偶氮胭脂红B的光催化降解性能。实验结果表明,羟基铁铝柱撑膨润土具有高的光催化活性。偶氮胭脂红B的光助Fenton脱色过程服从伪一级动力学模型,与染料脱色相比,偶氮胭脂红B溶液的总有机碳(TOC)去除速率相对较为缓慢。在偶氮胭脂红B初始质量浓度为100mg/L、双氧水浓度为12mmol/L、pH等于4时,反应达到平衡后偶氮胭脂红B的脱色率达到98.21%,TOC去除率达到98.12%。实验结果结合偶氮胭脂红B光催化过程的紫外-可见扫描图谱探讨了偶氮胭脂红B的矿化历程。

Hydroxy-iron-aluminum pillared bentonite was synthesized with ion exchange method,and its catalyst characteristics were analyzed by X-ray diffraction（XRD）and UV-vis diffuse reflectance spectra.The photo-Fenton catalytic activity of hydroxy-iron-aluminum pillared bentonite was tested under different reaction condition using azocarmine B as model pollutant under UV light.It is indicated that hydroxy-iron-aluminum pillared bentonite has high photocatalytic activity and the discoloration of azocarmine B in photo-Fenton process fits pseudo-first-order kinetic models.Compared to the decolor rate of azocarmine B,the removal of Total Organic Carbon（TOC）is comparatively slow.Under reaction condition with initial azocarmine B concentration of 100mg/ L,[H2O2]0=12mmol/L and pH=4,the removal rates of color and TOC were over 98.21%and 98.12%respectively after the equilibrium established.The mineralization way of azocarmine B was also exploited by UV-vis spectra of the azocarmine B solution in heterogeneous photo-Fenton process and analysis results.