作　　者： ; ;

机构地区： 华南农业大学食品学院

出　　处： 《食品工业科技》 2019年第21期13-19,共7页

摘　　要： 为了解负载型TiO2对乌龙茶中三唑磷紫外光催化降解的影响,在自制的光催化反应器中,采用负载型TiO2对三唑磷进行光催化降解。考察了煅烧温度、TiO2浓度和TiO2与聚乙烯吡咯烷酮(PVPK30)的含量比对三唑磷降解效果的影响,探究了三唑磷的降解途径,并通过X射线衍射和X射线光电子能谱对TiO2进行表征。结果表明,光催化降解三唑磷符合一级动力学方程,最佳制备参数为煅烧温度500℃,TiO2浓度0.15%,TiO2与PVPK30的含量比1∶1(m/m),反应时间10 min,在此条件下,三唑磷降解率可达98%。经气相色谱-质谱(GC-MS)联用技术分析可知光催化降解反应打断了三唑磷P-O酯键。XRD和XPS分析表明煅烧可影响纳米二氧化钛的粒径和晶型,温度越高,锐钛矿质量分数越小;500℃时,TiO2羟基氧和Ti3+的含量均较高。 In order to study the effect of supported TiO2 on the ultraviolet photocatalytic degradation of triazophos in oolong tea,the photocatalytic degradation of triazophos was carried out by using supported TiO2 in a self-made photocatalytic reactor.The effects of calcination temperature,concentration of TiO2 and the ratio of TiO2 to PVPK30 on the degradation of triazophos were investigated,and the degradation pathway of triazophos was explored.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS)were used to analyze the characterization of TiO2.The results showed that the photocatalytic degradation of triazophos accorded with the first-order kinetic equation.The optimum preparation parameters were calcination temperature 500℃,TiO2 concentration 0.15%,content ratio of titanium dioxide to PVPK301∶1(m/m),reaction time 10 min.Under these conditions,more than 98%of triazophos residues could be degraded within 10 min.GC-MS analysis showed that the P-O ester bond of triazophos was broken by photocatalytic degradation reaction.XRD and XPS analysis showed that calcination could affect the particle size and crystal form of TiO2.The mass fraction of anatase decreased with the increase of temperature.The content of TiO2 hydroxyl oxygen and Ti3+were both at high level at 500℃.

关 键 词： 二氧化钛 三唑磷 光催化降解 乌龙茶

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