天然地质样品有机质组成对菲吸附-解吸的影响

The Relationship between the Composition of Organic Matter in Natural Geo-Sorbents and Sorption-Desorption of Phenanthrene

以2种有机碳含量、结构和性质都相差较大的天然样品Chelsea土壤和Paxton页岩为吸附剂,以菲为吸附质进行一系列的吸附-解吸实验。结果显示,当土壤有机质是以腐殖酸为主时(Chelsea土壤),样品对疏水性有机化合物的吸附很容易达到平衡,解吸与吸附之间的滞后现象不是很明显。相反,对以干酪根为主要组成的Paxton页岩样品,吸附与解吸之间有明显滞后现象发生,吸附与解吸是一个完全不可逆过程。这说明土壤有机质组成和结构上的差异可能会成为决定有机污染物环境行为的主要因素。

Two natural samples,Chelsea soil and Paxton shale which have different organic content,chemical and physical properties each other,were chosen as sorbents for a sequential desorption experiment.The results show that while the major composition of organic matter of sorbent consists of humic acid(Chelsea soil),sorption of phenanthrene for soil sample is easy to get equilibrium and no clearly hysteresis exists between sorption and desorption.In reverse,for Paxton shale,because the organic matter is mainly made up by kerogean,hysteresis phenomenon could be observed,and sorption and desorption are a totally irreversible process.This implies that the difference of composition,structure and properties of organic matter of natural geo-sorbents is a major factor to control the environmental behavior of organic pollutants.