Sorption of phthalate acid esters on black carbon from different sources.
Sorption of phthalate acid esters on black carbon from different sources.
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DOI：
10.1039/c1em10072f
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发表时间：
2011-10
期刊：
影响因子：
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通讯作者：
X. Xia;Zhineng Dai;Ju Zhang
中科院分区：
文献类型：
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作者：
X. Xia;Zhineng Dai;Ju Zhang
炭黑(BC)对平面疏水有机物(HOCs)具有很强的吸附能力，但有关非平面疏水有机物在BC上的吸附信息却很少。研究了从河流沉积物中采集的环境细菌和纯细菌(炭木、炭秆和烟灰)对邻苯二甲酸二乙基己酯(DEHP)的吸附作用。除烟灰外，DEHP在纯BC和环境BC上均表现出较强的非线性吸附，Freundlich指数在0.55~0.75之间，测得的K(BC)(BC-水分配系数)比其有机碳水分配系数高一个数量级。环境细菌与纯细菌的吸附能力有显著差异。邻苯二甲酸二甲酯(DMP)的存在会显著降低DEHP在BC上的吸附，尤其是对环境BC。此外，当DEHP的平衡浓度小于10μg L(-1)时，BC对原始河流沉积物对DEHP总吸附的贡献大于50%。这项研究表明，邻位取代的非平面PAE也可以被BC强烈吸附，BC样品之间的吸附差异表明，在评估BC对水环境中HOCs去向的影响时，考虑BC的来源是很重要的。
Black carbon (BC) is known as a strong sorbent for the sorption of planar hydrophobic organic compounds (HOCs), but there is very little information about the sorption of nonplanar HOCs on BC. In this study, the sorption of di-(2-ethyl-hexyl) phthalate (DEHP), one kind of nonplanar phthalate acid ester (PAE), by environmental BC collected from river sediments and pure BC (char-wood, char-stalk and soot-ash) was investigated. Strong and nonlinear sorption was observed for the sorption of DEHP on both pure BC and environmental BC with the Freundlich exponent ranging from 0.55 to 0.75 except for soot-ash, and the measured K(BC) (BC-water partition coefficient) of DEHP was about one order of magnitude higher than its organic carbon-water partition coefficient. There was a significant difference in sorption capacity among the environmental and pure BC. The presence of di-methyl phthalate (DMP) could significantly decrease the sorption of DEHP on BC, especially for environmental BC. In addition, the contribution of BC to the total sorption of DEHP on original river sediments was more than 50% when the equilibrium concentration of DEHP was less than 10 μg L(-1). This study indicated that ortho-substituted nonplanar PAEs could also be strongly sorbed by BC, and the difference in sorption among the BC samples revealed that it is important to take the source of BC into account when assessing its effects on the fate of HOCs in aquatic environment.