臭氧对阳离子染料的脱色研究

RESEARCH ON THE DECOLORIZATION EFFICIENCY BY OZONE AND RESIDUES OF CATIONIC DYES

考察了臭氧对阳离子红GTL、阳离子蓝FGL、阳离子桃红FG的色度脱除、溶液pH值和TOC浓度的变化情况,并对降解后溶液中的残留物进行了分析。结果发现,染料脱色效果明显,20min脱色率均达到79.5%以上;有酸性物质生成并使得溶液的pH值随反应时间下降;生成CO2或可挥发性的有机物使得溶液的TOC浓度逐渐降低,40minTOC浓度下降率均达到21.9%以上;TOC、pH与脱色率在总体上变化趋势一致。反应中,染料分子中的-SO3H、-Cl基团均大部分生成了-SO42-、Cl-,PO43-以游离的H2PO4-存在于溶液中,氮则是根据基团的不同而部分被降解生成NO3-。

The decolorization of Cationic Red GTL, Cationic Blue FGL, Cationic Pink FG by ozone, and the changing ofpH value, TOC concentration were investigated with analysing the residues in the degrading solution. The results indicated that the decolorization effects were obvious, and the decol- orization efficiency of three dyes all reached to over 79% in 20min. The results also showed that some acid materials could be produced, causing pH value lowering with the reaction time lapsing. CO2 or volatile organic compounds produced, caused TOC concentration lowering, and the lowering rate all reached to over 21.9% in 40min. The trends of the pH and TOC changing were totally consistent with that of the decoloziration efficiency. Through the reaction, the complicated dye molecules were degraded to the simple organic compounds, and -SOrH,-C1 in the dye molecules were generated into SO^2-4,C1^-, and PO^3-4 ;they existed in the solution in the form of free H2PO4, while Nitrogen was partially degraded to NO^-3 on the basis of different groups.