pH及离子强度对渗滤液水溶性有机物同步荧光光谱的影响

采用同步荧光光谱技术分析填埋场不同填埋时期渗滤液水溶性有机物的理化性质,研究填埋场不同填埋时期渗滤液水溶性有机物(DOM)在三个代表性pH和不同离子强度下的同步荧光特性。结果表明,pH及离子强度对DOM的荧光性质都有较大影响。DOM的荧光特性受pH影响显著,填埋前、中、后期DOM在不同pH下的荧光峰位置与强度均不一致。离子强度对DOM荧光特性影响相对较小,由于盐析等作用,随离子强度的增加,各DOM的荧光强度一般都在降低。填埋前、中期DOM在pH 13时随离子强度的变化较显著,而填埋后期DOM在pH 3时随离子强度的变化较显著。研究为填埋场渗滤液溶解性有机物的毒性评价和污染防治提供了基本信息。

Effect of pH and ionic strength on synchronous fluorescence spectra of dissolved organic matter in landfill leachate

Spectroscopic characteristics of dissolved organic matter(DOM) in leachate with different landfill ages in three pH values and different ionic strengths were determined through synchronous fluorescence spectrometry(SFS).The result of SFS showed that spectroscopic characteristics of DOM were highly influenced by pH.The position and intensity of fluorescence peaks were different for DOM in young,medium and old landfill ages.Spectroscopic characteristics of DOM were less sensitive to ionic strength.Most fluorescence intensity was decreased with ionic strength increasing due to salting-out effect.The fluorescence intensity changed distinctly with ionic strength in pH 13 for DOM in young and medium landfill age,However,it changed distinctly in pH 3 for DOM at the old landfill age.It concluded that both pH value and ionic strength influenced fluorescence characteristics for DOM in leachate.The result might provide the basic information to pollution prevention and toxicological evaluation for leachate pollution.