甲基橙对含钛炉渣可见光催化还原Cr(Ⅵ)的影响

Visible Light-Induced Photocatalytic Reduction of Cr(Ⅵ) in Presence of Methyl Orange and Titania-Bearing Blast Furnace Slag Photocatalysts

采用硫酸盐掺杂的含钛高炉渣(sulfate-modified titania-bearing blast furnace slag,STBBFS)作为光催化剂,研究了可见光下,Cr(Ⅵ)单一体系和Cr(Ⅵ)-甲基橙(Cr(Ⅵ)-methyl orange(MO))复合体系对STBBFS光催化活性的影响.结果表明:酸性条件下,存在甲基橙时,Cr(Ⅵ)的光催化还原效率明显增强,Cr(Ⅵ)-MO复合体系中Cr(Ⅵ)的还原效率是Cr(Ⅵ)单一体系的1.35倍.Cr(Ⅵ)-MO复合体系中,Cr(Ⅵ)和MO的协同效应因子分别为18.3和39.8,说明Cr(Ⅵ)和MO之间存在较强的协同效应,存在有机物易于提高Cr(Ⅵ)的可见光催化还原效率.电解质对Cr(Ⅵ)的还原效率影响不大,但是对甲基橙的脱色率却有较大的影响,不同电解质对MO脱色率的促进作用按Na2SO4<NaCl<NaNO3逐渐增强.

The feasibility to enhance the visible light-induced photocatalytic reduction efficiency of Cr（Ⅵ） in the presence of methyl orange（MO） and sulfate-modified titania-bearing blast furnace slag（STBBFS） photocatalyst was investigated at the different pH and different initial concentrations.The results showed that in the presence of MO,the photocatalytic reduction efficiency of Cr（Ⅵ） is significantly enhanced and the kinetic constant of compound systems is nearly 1.35 times higher than that of single Cr（Ⅵ）.There exists a strong synergistic effect in the compound system,and the synergistic effect factors of Cr（Ⅳ） and MO are 18.3 and 39.8,respectively.During the whole experiment,the reduction efficiency of Cr（Ⅵ） and the decoloration efficiency of MO in the compound system are much higher than that of other two single systems.The presence of Na2SO4,NaCl,or NaNO3 in the reaction mixture has little effect on Cr（Ⅵ） reduction,but has a significant influence on the decoloration efficiency of MO.