Fe3O4/g-C3N4活化过硫酸盐降解罗丹明B的研究

Degradation of rhodamine B by Fe3O4/g-C3N4 activated sodium persulfate

以片状g-C3N4、六水三氯化铁、柠檬酸三钠和尿素为原料,聚丙烯酰胺为稳定剂,采用水热法制备Fe3O4/g-C3N4复合材料并作为过硫酸钠(PS)降解罗丹明B(RhB)的活化剂。通过XRD、SEM、EDS、FT-IR对样品结构、形貌与组成进行表征。考察Fe3O4与g-C3N4的质量比、活化剂质量、PS质量、溶液pH等对Fe3O4/g-C3N4活化PS降解RhB效果的影响。结果表明,与g-C3N4复合有效提高了Fe3O4的分散性和活化性能;在Fe3O4与g-C3N4质量比为3∶4、Fe3O4/g-C3N4质量为50 mg、PS质量为20 mg、RhB溶液pH为2.1时,反应120 min RhB的降解率达到100%。Fe3O4/g-C3N4可用磁铁进行分离回收,循环使用5次,活化PS去除RhB降解率仍达95.5%。

Fe3O4/g-C3N4 composites,which are prepared by hydrothermal method through using g-C3N4 sheet,ferric chloride hexahydrate,trisodium citrate and urea as raw materials,and polyacrylamide as stabilizer,is used as an activator of sodium persulfate for the degradation of rhodamine B(RhB).The structure,morphology and composition of the composites are characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),Energy Dispersive X-ray spectroscopy(EDS)and Fourier transform infrared spectroscopy(FTIR).The effects of the mass ratio of Fe3O4 to g-C3N4,the dosages of Fe3O4/g-C3N4 and PS,and pH value of RhB solution on the performance of Fe3O4/g-C3N4 activating PS for the degradation of RhB are investigated.Results show that the combination of Fe3O4and g-C3N4 has significantly improved the dispersion and the activating performances of Fe3O4.The degradation rate of RhB can reach 100%in 120 min of oxidization with PS when the mass ratio of Fe3O4/g-C3N4 is 3∶4,the dosages of Fe3O4/g-C3N4 and PS are 50 mg and 20 mg,respectively,and pH value of RhB solution is 2.1.The degradation rate of RhB by Fe3O4/g-C3N4 activated PS can still reach 95.5%after Fe3O4/g-C3N4 composites are separated and recovered by magnet for five times.