摘要
利用改性沸石负载Fe_3O_4活化H_2O_2非均相Fenton体系氧化降解有机污染物亚甲基蓝。考察了催化剂改性沸石负载Fe_3O_4投加量、溶液初始pH和H_2O_2初始浓度对亚甲基蓝降解效果的影响,进而讨论Fe_3O_4/改性沸石-H_2O_2非均相Fenton体系的催化机理。结果表明,当催化剂投加量为2.40 g/L,初始溶液pH为5.33,H_2O_2浓度为5.93 mmol/L时,反应30 min后,9.60 mol/L的亚甲基蓝去除率可达到98.52%。通过自由基捕获剂抗坏血酸和羟基自由基捕获剂甲醇,证明了Fe_3O_4/改性沸石-H_2O_2体系的氧化物种为羟基自由基和过氧自由基。
The heterogeneous Fenton system using Fe_3O_4 modified zeolite immobilized and H_2O_2 was developed to remove organic pollutant of methylene blue. The catalytic mechanism of methylene blue in the above heterogeneous Fenton system,and the load of catalyst,pH and the initial concentration of H_2O_2 were investigated. The results show that when the catalyst load was 2. 40 g/L,initial pH value was 5. 33 and the initial concentration of H_2O_2 is 5. 93 mmol/L,the removal efficiency of methylene blue of9. 60 mol/L is 98. 52% after 30 min reaction. By adding the ascorbic acid( free radical scavenger) and methanol( hydroxyl free radical scavenger),it was proved the oxidative speciesin Fe_3O_4/modified zeoliteH_2O_2 system were the hydroxyl free radicals and the oxygen free radicals.
引文
[1]Glaze W H,Kang J W,Chapin G H.The chemistry of wastewater treatment processes involving ozone,hydrogen peroxide and ultraviolet radiation[J].Ozone:Science&Engineering:The Journal of the International Ozone Association,1987(9):335-341.
[2]张光明,张盼月,张信芳.水处理高级氧化技术[M].哈尔滨:哈尔滨工业大学出版社,2007.
[3]Kong S H,Watts R J,Choi J H.Treatment of petroleum contaminated soils using iron mineral catalyzed hydrogen peroxide[J].Chemosphere,1998,37(8):1473-1482.
[4]Neamtu M,Yediler A,Siminiceanu I,et al.Oxidation of commercial reactive azo dye aqueous solutions by the photo-Fenton and Fenton-like processes[J].Journal of Photoch and Photobiology A:Chemistry,2003,161(1):87-93.
[5]李冬梅,徐光亮.制备超顺磁性Fe3O4纳米粒子的研究进展[J].中国粉体技术,2008,14(4):55-58.
[6]李大群,蒋进元,周岳溪,等.载铁沸石催化H2O2降解阳离子红X-GRL染料废水[J].环境工程技术学报,2013,3(5):391-397.
[7]张瑛洁,马军,柳旭升,等.微波改性沸石/类芬顿技术的脱色效果[J].中国给水排水,2009,25(13):83-85.
[8]孙杨,弓爱君,宋永会,等.沸石改性方法研究进展[J].无机盐工业,2008,40(5):1-4.
[9]王琳,孙成.沸石负载四氧化三铁基于微波-UV装置降解甲基紫废水[D].南京:南京大学,2012.
[10]Lin S S,Gurol M D.Catalytic decomposition of hydrogen peroxide on iron oxide:kinetics,mechanism and implications[J].Environmental Science&Technology,1998,32(10):1417-1423.
[11]柴多里,刘忠煌,陈刚,等.水热法合成纳米Fe3O4及其对含酚废水的处理[J].硅酸盐学报,2010,38(1):105-109.
[12]张国卿,王罗春,徐高田,等.Fenton试剂在处理难降解有机废水中的应用[J].工业安全与环保,2004,30(3):17-19.
[13]邓景衡,文湘华,李佳喜.碳纳米管负载纳米四氧化三铁多相类芬顿降解亚甲基蓝[J].环境科学学报,2014,34(6):1436-1442.
[14]刘琰,孙德智.高级氧化技术处理染料废水的研究进展[J].工业水处理,2006,26(6):1-5.
[15]朱舜,姚玉元.Fenton-like催化纤维的制备及其催化氧化染料的研究[D].杭州:浙江理工大学,2013.
[16]Doorslaer X V,Heynderickx P M,Demeestere K,et al.Ti O2mediated heterogeneous photocatalytic degradation of moxifloxacin:operational variables and scavenger study[J].Applied Catalysis B:Environmental,2012,111/112:150-156.
[17]Pang S Y,Jiang J,Ma J.Response to comment on“Oxidation of sulfoxides and Arsenic(III)in corrosion of nanoscale zero valent iron by oxygen:evidence against ferryl ions(Fe(IV))as active intermediates in Fenton reaction”[J].Environmental Science&Technology,2011,45:3179-3180.