1,3,5-三氯苯在土壤沉积物水体系中的吸附过程研究

以自然土壤、沉积物样品为研究对象，研究了1，3，5-三氯苯在样品上的等温吸附过程。结果表明，线性模型和Freundlich模型能较好地拟合所有样品的等温线，而双区位反应模型(DRDM)适用范围有限。研究表明，三氯苯的吸附容量大小主要取决于样品中有机碳的含量，并且与不可提取态有机质和粘土矿物含量有一定的关系。

Sorption Equilibria of 1, 3, 5 - trichlorobenzene by Soil and Sediment in Water Body

Sorption-desorption to natural so il/sediment i s an underlying process affecting the transport,degradation,and biolog-ical act ivity of hydrophobic organi c contaminants(HOCs )in the environment.Mineral f ractio ns and soil organic matters(SOM)in soil/sediment play important roles in determining the sorption and deso rption patterns of hydrophobic orga nic co ntaminants.For these contaminants,the mineral fra ctions of soil/sediment pl ay minor r oles than SOM.Much recent work has re vealed that content and natur e of organic matter have a significant impact on sorption capacity and nonlinear ity.In the paper,we used 1,3,5-trichlorobenzene as a probe to explo re sorption of hydrophobic organic c ompounds by soil/sediment from aqueous solut ion.Sorption isotherms for 1,3,5-trichlorobenzene were measured experimen tally fo r different soils and sediments.The linear and Freundlich isotherm mod els and the dual reactiv e domain model(DRDM)were used to fit the resulting da ta.T he results reveal that:the linear model was not appropriate for describin g any of the experimental sorptio n data,and the Freundlich model was f ound to be adequate for all samples,while DRDMwas appropriate only for some samples.A ll isotherms were nonlinear,Freundlich exponents(n)ranged from 0.756to 0.935for 1,3,5-trichl orobenzene.Sorption capacity of hydrophobic or ganic contaminants relates directly to the content of SOM,and the content of cl ay minerals may b e a critical factor.The base extracted samples exhibit signif icantly hi gher sorption capacities and more nonlin ear than these untreated sam ples,which suggest that the presence of small amounts of humin and some special carbon materials may be responsible for the observed nonlin ear sorption.