学术论文

      臭氧氧化法降解浮选废水中残余BK809

      Degradation of residual BK809 in flotation wastewater by ozonation

      摘要:
      采用臭氧氧化法对模拟浮选废水中BK809进行降解处理,并对不同阶段的降解产物进行气相色谱--质谱(GC-MS)分析.结果表明,废水的最佳处理pH值为9~11,当臭氧投加速度为300mg.h-1、臭氧处理时间为20min时,废水中COD去除率为68.68%.GC-MS分析显示:BK809的总降解过程为苯胺首先被氧化成偶氮苯,然后转化为硝基苯,随着氧化的加深,苯环被打开,进一步氧化分解为C15~C25的链状烷烃和气态物质,包括氮的氧化物和碳的氧化物;最终废水中总有机物的质量残留率由原来的100%下降至17.18%.在此过程中,废水的色度则由5.02度逐渐上升至471.71度,然后又逐步下降至28.75度,从宏观上表现为由无色变为棕黄色,又从棕黄色逐渐还原为乳白色.
      Abstract:
      Ozonation was used to degrade residual BK809 in flotation wastewater and the degraded products in different stages were identified and quantified by gas chromatography-mass spectrometry(GC-MS).The results showed that the COD removal rate of 68.68% could achieve at an ozone flow rate of 300mg·h-1 for 20min and pH 9-11.It was indicated from GC-MS analysis that BK809 was firstly oxidized to azobenzene and then converted to nitrobenzene.With the deepening of ozonation,the benzene was broken and further decomposed into C15-C25 carbon-chain alkanes and gaseous substances,including nitrogen oxides and carbon oxides.Finally the residual mass percentage of total organic compounds(TOC) reduced from 100.00% to 17.18%.Meantime,the chroma of the wastewater increased from 5.02 to 471.71 and then decreased to 28.75;in macroscopic view,the color of the wastewater turned from colorless to brown,and then from brown to milky.
      作者单位: 北京科技大学土木与环境工程学院,北京,100083
      刊 名: 北京科技大学学报 ISTICEIPKU
      年,卷(期): 2011, 33(8)
      分类号: X751
      机标分类号: X70 O64
      在线出版日期: 2012年4月21日