Long Term Sorption Kinetics of Phenanthrene in Aquifer Materials

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• 作者：Hermann RÜ ; gner ; Sybille Kleineidam ; and Peter Grathwohl
• 刊名：Environmental Science & Technology
• 出版年：1999
• 出版时间：May 15, 1999
• 年：1999
• 卷：33
• 期：10
• 页码：1645 - 1651
• 全文大小：155K
• 年卷期：v.33,no.10(May 15, 1999)
• ISSN：1520-5851

文摘

Most aquifer materials are heterogeneous in terms ofgrain size distribution and petrography. To understandsorption kinetics, homogeneous subfractions, either separatedfrom heterogeneous sands and gravels (lithocomponents)or fragments of fresh rocks, have to be studied. In thispaper we present data on long-term sorption kinetics ofphenanthrene for homogeneous samples consisting of onetype of lithocomponents or fresh rock fragments indifferent grain sizes. Diffusion rate constants were determinedin batch experiments using a numerical model for retardedintraparticle pore diffusion and correlated to grain sizeand intraparticle porosity of the lithocomponents. Sorptionisotherms were nonlinear for all samples investigated(Kleineidam et al. (1)). The numerical model described thesorption kinetics very well for coarse sand and gravels.Tortuosity factors, which were obtained as final fitting factors,agreed with Archie's law predictions based on theintraparticle porosity. The dependency of sorptive uptakeon grain size revealed that for smaller grains intrasorbentdiffusion may become significant. This is attributed torelatively large particulate organic matter (POM) withinthe sedimentary rock fragments. Specifically, charcoal andcoal particles, which were found in some of the sandstones,controlled the sorptive uptake rates.