Two azo dyes,C.I.Reactive Red 195(RR195)and C.I.Acid Black 234(AB234)were degraded by photocatalysis of Fe(Ⅲ)-oxalate complexes/H2O2 in aqueous non-ionic surfactant,Triton X-100(TX-100)solution.Some factors affecting...Two azo dyes,C.I.Reactive Red 195(RR195)and C.I.Acid Black 234(AB234)were degraded by photocatalysis of Fe(Ⅲ)-oxalate complexes/H2O2 in aqueous non-ionic surfactant,Triton X-100(TX-100)solution.Some factors affecting the dye degradation such as TX-100 concentration,irradiation intensity,and sodium chloride were investigated.The interaction and competition between dye and TX-100 during the degradation were also examined using spectrophotometry and maximum bubble pressure method,respectively.The results indicated that TX-100 showed a significant reduction effect on degradation of two azo dyes,but which was largely confined to TX-100 concentration below the Critical Micellar Concentration(CMC).And the reduction was considerably decreased above the CMC,especially in the case of AB234.Moreover,the reducing effect of TX-100 on dye degradation almost did not vary with irradiation intensity.And the impact of sodium chloride on dye degradation was limited by the addition of TX-100.展开更多
The aqueous photodegradation of bisphenol A （BPA） in the presence of Fe（Ⅲ）-oxalate complexes （Fe（Ⅲ）-Ox）, which are common compositions of natural water, was investigated in this study. BPA underwent rapid in...The aqueous photodegradation of bisphenol A （BPA） in the presence of Fe（Ⅲ）-oxalate complexes （Fe（Ⅲ）-Ox）, which are common compositions of natural water, was investigated in this study. BPA underwent rapid indirect photolysis in Fe（Ⅲ）-Ox solution under simulated solar irradiation, proceeding pseudo-first-order kinetics. The photolysis rate increased with decreasing pH or initial BPA level and increasing Fe（Ⅲ）/oxalate concentration ratio. Hydroxyl radicals （·OH）, which were generated from the photochemical processes of Fe（Ⅲ）-Ox complexes and contributed to the photooxidation of BPA, were determined by molecular probe and electron spin resonance （ESR） methods with the steady-state concentration of 2.56 × 10^-14 mol/L. Superoxide anion radical （O2^·-） was considered as the precursor of. OH and qualitatively determined by adding nitro blue tetrazolium as well as ESR experiments. Based on the structural analysis of the intermediate photoproducts of BPA in Fe（Ⅲ）-Ox complexes solution, the possible degradation pathways of BPA were proposed, involving ·OH addition, alkyl scission and alky oxidation. The results indicate that the photochemical reactivity of Fe（Ⅲ） may affect the environmental fate of BPA in natural water significantly.展开更多
在B3LYP/6-311+G(d,p)基组水平下采用密度泛函理论方法系统开展了以下工作:(1)优化得到1∶1、1∶2和1∶3铝-麦芽酚配合物10种可能构型的静态结构、NPA电荷以及能量参数,计算得到Al(ma)3配合物4种异构体的核磁共振、紫外和红外等光谱学...在B3LYP/6-311+G(d,p)基组水平下采用密度泛函理论方法系统开展了以下工作:(1)优化得到1∶1、1∶2和1∶3铝-麦芽酚配合物10种可能构型的静态结构、NPA电荷以及能量参数,计算得到Al(ma)3配合物4种异构体的核磁共振、紫外和红外等光谱学数据并与文献实验值比较,证明本文采用的计算方法和模型适用于铝-麦芽酚体系的研究;(2)模拟1∶1和1∶2铝-麦芽酚配合物9种可能位点的水交换反应,其中3个位点计算得到的水交换反应速率对数log kex(s-1)分别为2.4(Al(ma)(H2O)2+4(cis to ma))、2.6(cis-Al(ma)2(H2O)+2(I))和3.0(trans-Al(ma)2(H2O)+2(I)),与实验值2.5(Al(ma)2+)和3.3(Al(ma)+2)相符,说明相应位点为反应活性位点;(3)探讨铝-麦芽酚配合物毒性与其形态结构之间的相关机制。展开更多
基金National Natural Science Foundation of China(No.20773093)Tianjin Municipal Science Programme Foundation,China(No.043605911)
文摘Two azo dyes,C.I.Reactive Red 195(RR195)and C.I.Acid Black 234(AB234)were degraded by photocatalysis of Fe(Ⅲ)-oxalate complexes/H2O2 in aqueous non-ionic surfactant,Triton X-100(TX-100)solution.Some factors affecting the dye degradation such as TX-100 concentration,irradiation intensity,and sodium chloride were investigated.The interaction and competition between dye and TX-100 during the degradation were also examined using spectrophotometry and maximum bubble pressure method,respectively.The results indicated that TX-100 showed a significant reduction effect on degradation of two azo dyes,but which was largely confined to TX-100 concentration below the Critical Micellar Concentration(CMC).And the reduction was considerably decreased above the CMC,especially in the case of AB234.Moreover,the reducing effect of TX-100 on dye degradation almost did not vary with irradiation intensity.And the impact of sodium chloride on dye degradation was limited by the addition of TX-100.
文摘The aqueous photodegradation of bisphenol A （BPA） in the presence of Fe（Ⅲ）-oxalate complexes （Fe（Ⅲ）-Ox）, which are common compositions of natural water, was investigated in this study. BPA underwent rapid indirect photolysis in Fe（Ⅲ）-Ox solution under simulated solar irradiation, proceeding pseudo-first-order kinetics. The photolysis rate increased with decreasing pH or initial BPA level and increasing Fe（Ⅲ）/oxalate concentration ratio. Hydroxyl radicals （·OH）, which were generated from the photochemical processes of Fe（Ⅲ）-Ox complexes and contributed to the photooxidation of BPA, were determined by molecular probe and electron spin resonance （ESR） methods with the steady-state concentration of 2.56 × 10^-14 mol/L. Superoxide anion radical （O2^·-） was considered as the precursor of. OH and qualitatively determined by adding nitro blue tetrazolium as well as ESR experiments. Based on the structural analysis of the intermediate photoproducts of BPA in Fe（Ⅲ）-Ox complexes solution, the possible degradation pathways of BPA were proposed, involving ·OH addition, alkyl scission and alky oxidation. The results indicate that the photochemical reactivity of Fe（Ⅲ） may affect the environmental fate of BPA in natural water significantly.
文摘在B3LYP/6-311+G(d,p)基组水平下采用密度泛函理论方法系统开展了以下工作:(1)优化得到1∶1、1∶2和1∶3铝-麦芽酚配合物10种可能构型的静态结构、NPA电荷以及能量参数,计算得到Al(ma)3配合物4种异构体的核磁共振、紫外和红外等光谱学数据并与文献实验值比较,证明本文采用的计算方法和模型适用于铝-麦芽酚体系的研究;(2)模拟1∶1和1∶2铝-麦芽酚配合物9种可能位点的水交换反应,其中3个位点计算得到的水交换反应速率对数log kex(s-1)分别为2.4(Al(ma)(H2O)2+4(cis to ma))、2.6(cis-Al(ma)2(H2O)+2(I))和3.0(trans-Al(ma)2(H2O)+2(I)),与实验值2.5(Al(ma)2+)和3.3(Al(ma)+2)相符,说明相应位点为反应活性位点;(3)探讨铝-麦芽酚配合物毒性与其形态结构之间的相关机制。
