植物法改性类Fenton反应催化剂降解甲基橙

采用银杏叶和桑叶提取液制备了改性类Fenton反应催化剂并进行了表征分析,研究了溶液初始p H、反应温度、催化剂加入量、甲基橙初始质量浓度等因素对甲基橙降解率的影响,同时考察了催化剂的重复使用效果。表征结果表明:制备出的催化剂为Fe_2O_3和Fe OOH的混合物;桑叶改性催化剂的粒径分布较银杏叶改性催化剂均匀,粒径较小,比表面积较大。实验结果表明:在初始p H为6.23、反应温度60℃、催化剂用量1 g/L、甲基橙初始质量浓度100 mg/L的条件下,银杏叶改性催化剂的甲基橙降解率为99.40%,桑叶改性催化剂的甲基橙降解率为99.96%;碱性条件下,甲基橙降解率仍接近100%,扩宽了反应的p H适用范围,为碱性条件下处理偶氮染料提供了新思路;催化剂重复使用6次之后,甲基橙降解率仍可达到99%。根据反应前后溶液的紫外-可见吸收光谱,初步探讨了降解机理。

Degradation of methyl orange using plant modified catalyst for Fenton-like reaction

The modified catalysts for Fenton-like reaction were prepared using extracts of ginkgo leaf and mulberry leaf,and were characterized. The factors affecting the degradation rate of methyl orange were studied,and the reusability of the catalysts was researched. The characterization results show thatThe prepared catalysts are mixtures of Fe₂O₃ and FeOOH;Comparing with the catalyst modified using ginkgo leaf,the particles of the catalyst modified using mulberry leaf are more uniform with smaller size and larger specific surface area. The experimental results show thatUnder the conditions of initial pH 6.23,reaction temperature 60 ℃,catalyst dosage 1 g/L and initial mass concentration of methyl orange 100 mg/L,the degradation rates of methyl orange on the catalysts modified using ginkgo leaf and mulberry leaf are 99.40% and 99.96% respectively;The degradation rates of methyl orange keep nearly 100% under alkaline condition,which indicate that the pH range for reaction is enlarged and this provides a new way for degradation of azo dye under alkaline condition;After the catalyst has reused for 6 times,the degradation rates of methyl orange can still reach 99%. According to the UV-Vis absorption spectrum of the solutions before and after reaction,the degradation mechanism was discussed.