摘要
采取北京城区表土样品和土壤标准参考样共7件,对原土样以及经H2O2氧化处理去除低聚合有机碳后的土样分别采用静态批实验方法,研究其对三氯乙烯(TCE)的等温吸附方程。实验结果表明7种土样对TCE的吸附模式均符合线性等温吸附方程,采用H2O2氧化去除土壤样品中的低聚碳,并没改变等温吸附线型,只是方程的参数发生了变化。剩余有机碳的含量仍都大于0.1%,仍然以有机碳的吸附为主;原土样、高聚碳、低聚碳对TCE吸附均表明,有机碳的含量与样品吸附TCE的能力没有明显的关系,证实不管是总有机碳、低聚碳还是高聚碳都有明显的异质性,它们所表现出来的吸附能力并不相同,有机碳结构组成的差异往往是影响其吸附的关键因素。而土壤有机碳经历矿化和腐殖化程度的差异是造成土壤有机碳结构组成差异的主要原因。
In order to study the impact of the soil organic carbon content and soil organic carbon heterogeneity on the sorption behavior of trichloroethylene （TCE）,the authors collected 7 soil samples including 3 surface soil samples of Beijing urban area and 4 soil standard reference samples.These 7 samples were treated by using H2O2 to remove the lower aggregate carbons （LAC）.Both treated and untreated soil samples were used to carry out statistic batch tests on the TCE isotherm sorption patterns.The results show that the isotherm adsorption patterns fit the liner sorption model very well both for the treated and untreated soil samples.The removal of LAC did not change the sorption model type,and only changed the parameters of the liner formulae.The residual organic carbon content of all the samples remained higher than 0.1%,and the organic carbons still played the main role during the sorption.The results also show that there exist no apparent relationships between the soil sample sorption capabilities and different kinds of organiccarbon content,i.e.,the total organic carbon （TOC） content and the higher aggregate carbon （HAC） content and LAC content,and the total sorption capabilities of 7 original soil samples used in these tests are mainly determined by the LAC sorption capabilities.These data have confirmed the fact that TOC,LAC and HAC all have obvious heterogeneities,i.e.,the same soil organic carbon content will have different sorption capabilities.The difference in organic carbon construction and components is the key factor affecting the sorption behavior.Unless the difference in organic carbon construction and components is negligible,the organic carbon content will play an important role in affecting the TCE sorption behavior.However,the heterogeneities of soil organic carbons are mainly caused by the difference in mineralization and humification.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2010年第3期325-330,共6页
Acta Petrologica et Mineralogica
基金
国家自然科学基金项目(40702060)
863国家高技术研究发展计划(2006AA100205-3)
关键词
土壤有机碳
三氯乙烯
吸附行为
异质性
soil organic carbon
trichloroethylene（TCE）
sorption behavior
heterogeneity
