Ti/MCM-22/MCM-41微介孔复合材料光催化降解酸性红B模拟废水的研究

Photocatalytic degradation of acid red B by Ti/MCM-22/MCM-41 micro-mesoporous composite materials

采用纳米自组装法制备了具有吸附性和光催化性的Ti/MCM-22/MCM-41微介孔复合材料,利用X射线衍射、N2吸附、扫描电镜等方法对其进行表征。将复合材料用于光催化降解酸性红B的实验,考察了催化剂用量、光照时间、pH值和染料初始浓度对光催化降解率的影响,并对光降解产物进行了紫外光谱分析。结果表明:当染料的初始浓度为50 mg/L,废水pH在6左右,催化剂投加量为0.1 g/L,光照时间120 min,酸性红B的去除率可达98%以上,光催化降解反应遵循一级反应动力学方程。降解产物的紫外光谱图表明,降解后酸性红B的两个特征吸收带消失,结构的共轭系被打破,颜色消失,说明该复合材料去除水中的酸性红B主要是通过光催化作用。

A novel Ti/MCM-22/MCM-41 composite material was prepared by Nano self-assembly method.The synthesized material was characterized by XRD,N2 adsorption,SEM,and subsequently applied in the Acid Red B degradation.Several parameters such as dosage of catalyst,reaction time,pH of wastewater,and initial concentration of dye were systematically investigated.The oxidation products were analysed by ultraviolet spectrum.The results showed the highest removal efficiency up to 98% could be achieved when initial concentration of acid red B,pH of wastewater,amount of catalyst and reaction time were as 50mg/L,6,0.1g/L and 120min respectively.The process of the catalyst reaction was accordant with first order kinetics equation.The ultraviolet spectrogram indicated two characteristic absorption bands of acid red B disappeared after degradation,structure of conjugated system was broken,and color of wastewater disappeared.It demonstrated the degradation of acid red B was mainly through photocatalysis of the composite material.