为了评价Fenton法预处理抗生素生产废水中残留的高浓度土霉素的可行性,对Fenton试剂(Fe2+-H2O2)法催化氧化降解水溶液中的土霉素进行了研究。探讨了H2O2与Fe2+投加比例、投加量以及起始pH值对降解效果的影响,同时考察了土霉素废水中大量共存的草酸根离子对氧化过程的影响。结果表明,当H2O2与Fe2+按照5∶1的比例投加时降解效率最高,最佳初始pH值在3.0~4.0之间。在最佳投加比例下,H2O2投加量为0.9 mmol/L,100 mg/L的土霉素可在10 min内得到完全降解。最佳反应条件下经过处理后土霉素水溶液TOC的去除率达40%左右,可生化性(BOD5/COD)也得到明显的改善。水中共存的草酸根离子对氧化效率具有明显的影响,但通过增加亚铁离子的量可以消除草酸的影响。
Degradation of oxytetracycline by Fenton reaction was studied in this paper. The influences on the degradation rate of reaction conditions were discussed. Moreover, the effect of oxalic acid on oxytetracycline degradation was studied. The results showed that the optimum ratio of hydrogen peroxide and ferrous is 5 to 1, and the optimum pH occurred at 3.0 - 4.0. Under the optimal conditions of that initial pH = 3, [ H2O2 ] = 0.9 mmol/L, the ratio of H2O2/Fe2+ = 5, and reaction time = 30min, 100 mg/L oxytetracycline was completely degraded within 10 min , correspondingly 40% TOC removal and significant improvement of biodegradability were observed. Oxalic acid present in solutions suppressed the oxidation efficiency while its inhibition influence could be eliminated by the excessive add of ferrous.