研究了天然水体条件下2种合成有机污染物(SOC)甲基对硫磷(MP)和三氯乙烯(TCE)以及天然有机物(NOM)在5种粉末活性炭(PAC)上的吸附特性.在对活性炭的物化特性进行全面表征的基础上,利用相关分析方法揭示了PAC的物理和化学性质对天然水体中SOC类小分子有机污染物吸附的影响;并利用高效体积排阻色谱法(HPSEC)研究了天然有机物(NOM)在PAC上吸附的分子量分级效应.结果表明,相对于表面化学性质而言,PAC的物理性质(孔隙性质)是影响其吸附2类有机污染物的主要因素;PAC对SOC类小分子有机污染物和表观相对分子质量(AMW)〈500的NOM的吸附主要受PAC的微孔比表面积的影响,而对AMW在500~3 000的NOM的吸附则受中孔比表面积和中孔孔径的共同影响.
In this paper,the adsorption characteristics of two synthetic organic compounds(SOCs),i.e.,methyl parathion(MP) and trichloroethylene(TCE),and natural organic matter(NOM) on powdered activated carbons(PAC) in natural water were studied.On the basis of fully characterizing the physical and chemical characteristics of PAC,the effect of physical and chemical properties of PAC on the adsorption of low molecular weight SOCs in natural water was studied by correlation analysis.The effect of molecular weight fractionation on the adsorption of NOM on PAC was investigated using high performance size exclusion chromatography(HPSEC).It was found that,compared to the surface chemistry,the physical property(pore properties) of PAC was the critical factor to determine its adsorption capacity of MP and TCE in natural water.The adsorption of the low molecular weight SOC and NOM with apparent molecular weight(AMW) 500 on PAC was primarily impacted by the micropore surface area,and that of NOM with 500 AMW 3 000 was affected by the mesopore surface area combined with the mesopore size distribution.