溴酸钾对二茂铁(Fc)非均相Fenton效能的影响

Effect of potassium bromate on efficiency of heterogeneous Fenton catalyzed by ferrocene

研究了KBrO3对二茂铁(Fc)非均相Fenton效能的影响,深入考察了KBrO3对体系中Fc溶解、H2O2分解和羟基自由基(·OH)生成的影响。结果表明,KBrO3的加入对不同反应阶段Fc/Fenton体系的效能均有明显的促进作用,初始阶段主要是由于KBrO3对·OH产生的促进作用所致,后期主要是由于KBrO3促进了体系中Fc的溶解,使得体系中溶解态的Fc催化的均相Fenton反应的比例增加,体系中H2O2的分解加快,·OH的表观生成率增加,进而促进了反应的进行。无KBrO3添加,pH=4,MB初始浓度为10 mg/L,Fc的量为1.6×10-3mol/L,[H2O2]/[MB]=3.14时,45 min时,MB的剩余率为9.1%,105 min时为0。当KBrO3的用量为3×10-4mol/L时,反应45 min后MB的去除率即可达到100%。随着KBrO3浓度的增加,其对Fc/Fenton效能的促进作用增强。

The effect of potassium bromate on the efficiency of the heterogeneous Fenton catalyzed by Ferrocene was investigated,as well as dissolution of Ferrocene(Fc),decomposition of H2O2 and generation of hydroxyl radicals(·OH).The results indicated that the addition of KBrO3 accelerated the discoloration of Methylene Blue at any time of the reaction,and the reasons are listed as follows: the generation of ·OH at the beginning of the reaction was improved,while the dissolution of Fc was accelerated by KBrO3 in the latter.The increased ratio of dissolved Fc on the dosage of Fc added at the initial of the reaction favored the decomposition of H2O2 and the generation of ·OH,leading to the improvement of the efficiency.Under the conditions of pH of 4,[MB]0= 10 mg/L,[Fc] = 1.6 × 10-3mol/L,[H2O2]/[MB]= 3.14,without KBrO3,the residual of MB in solution reached 9.1% at 45 min and 0 at 105 min.Under the same conditions,but in the presence of 3 × 10-4mol/L KBrO3,100% discoloration of MB was reached at 45 min.The efficiency of Fc/Fenton can be improved through increasing the concentration of KBrO3.