BiOI-TiO_2复合材料光催化降解双酚A的研究

Study on Nano Bismuth Oxyiodide-Titanium Dioxide Composite Particles and Photodegradation of Bisphenol A Under Visible Light Irradiation

采用Triton X-100/正己醇/环己烷/水的微乳体系合成了一系列BiOI-TiO2的纳米材料,分析了其晶体结构、表面结构和光谱特征,探讨了可见光光催化降解双酚A废水的可行性.结果表明:BiOI-TiO2的分散性能好、比表面积大.光催化结果表明,复合材料中BiOI与TiO2的摩尔比对光催化性能影响大且比值达到75%时效果最好.光催化降解机理符合一级动力学方程,反应速率常数(kobs)与催化剂投加量及初始pH值有关.催化剂重复多次使用的降解效果稳定.

This study synthesized a series of nanosized BiOI - TiO_2 catalysts to photodegrade bisphenol - A （BPA） solution. The BiOI -TiO_2 nanoparticles were synthesized in reverse mieroemulsions, consisting of cyclohexane, Triton X - 100, n - hexanol and aqueous salt solutions. The synthesized particles were characterized by X - ray dif- fraction （XRD） , Brunauer - Emmett - Teller （BET） surface analyzer and ultraviolet - visible light （ UV - Vis ） absorption spectra. The photodegradation of bisphenol A in aqueous suspension under visible light irradiation was investigated to explore the feasibility of using the photocatalytic method to treat BPA wastewater. The effects of dif- ferent molar ratios of BiOI to TiO_2 on the photoeatalytic activities of BiOI -TiO2composites were discussed. The ex- perimental results revealed that the photocatalytic activity of the BiOI - TiO2partieles were superior to the commer- cial P25 TiO_2. The BPA degradation could be approached by a pseudo -first order rate expression. The observed reaction rate constant （k_（obs）） was related to nanopartieles dosage and initial pH. The recycling experiments con- firmed the relative stability of the catalyst.