研究了以Cr(Ⅵ)为催化剂,用微波促进类Fenton反应催化氧化脱色降解有机染料罗丹明B及相关机理。内容包括:罗丹明B溶液的浓度-吸光度工作曲线绘制;初始pH值、H2O2用量、K2Cr2O7用量对类Fenton反应脱色降解罗丹明B的影响;正交优化试验;微波单独脱色处理罗丹明B、微波+K2Cr2O7脱色处理罗丹明B、微波+H2O2脱色处理罗丹明B、阳光-Cr(Ⅵ)-H2O2体系脱色处理罗丹明B、微波-Cr(Ⅵ)-H2O2体系脱色处理罗丹明B等对照试验研究。通过研究,确定了方法的优化条件,在优化条件下,比较了采用光助类Fenton与微波促进类Fenton反应的脱色效率,并讨论了微波促进类Wenton反应的反应机理。研究表明在pH3.0时,微波可以明显加快类Fenton法催化氧化脱色降解罗丹明B溶液的过程,对于降解脱色速度,微波-Cr(Ⅵ)-H2O2体系最快。用该方法处理染料罗丹明B,色度脱除率可达到99.0%以上。文章所用表征方法均为紫外-可见光谱法。
Microwave-promoted Fenton like reaction, the combination of Fenton-like reagent with microwave, is an efficient method for waste water treatment. In the present paper, the degradation of rhodamine B (a kind of organic dye) using this method was studied. Through numerous experiments, the influences of various parameters including the initial pH value, reaction time, dosage of K2Cr2O7, dosage of H2O2 and microwave were investigated intensively. The characteristic curve of rhodamine B, the concentration-absorbency curve of rhodamine B, the orthogonal optimization tests and comparative tests were given. The mechanism of this reaction was also probed. It is concluded from the experiments that the microwave can accelerate the process of degradation effectively. Under optimal conditions, the overall color removal was more than 99. 9% within 9 min. In the study, the method for characterization was entirely UV-Vis spectral analysis.