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Th.J.S. Keijzer (2000). "Chemical osmosis in natural clayey materials"
Geologica Ultraiectina, 196, Ph.D.-thesis, Universiteit Utrecht, Utrecht,
the Netherlands, 166 pp. ISBN 90-5744-053-9

brief outline of the thesis

The theoretical framework of semipermeability of natural clayey materials is discussed in Chapter 1. This chapter is also intended to give the reader a comprehensive overview of the available models and will introduce the terminology. It includes a detailed overview of the research carried out on semipermeability of natural earth materials, and addresses the role this may have on processes observed in geological systems.

Chapter 2 introduces and discusses the samples used in the experiments.

Chapter 3 contains a short description of the historical development of instrumention used for research of osmotic phenomena. Moreover, it describes a novel design based on a flexible wall permeameter used in this study. The design criteria are formulated and a description of the instrumentation is given together with the general experimental procedures. Its performance during several tests on clay and non–clay samples are discussed. The apparatus was used to determine the semipermeability of a commercially available Wyoming bentonite.

The results of these experiments are discussed in Chapter 4. Experiments were done on loose and more compacted samples of bentonite. Results were compared with the semipermeability predicted by three available models, and discussed within the context of earlier experiments on bentonite.

In Chapter 5 the experiments on the semipermeability of harbour sludge are presented and discussed. Again the applicability of the theory is compared with the experimental observations, and the relative importances of the factors that make the sludge a semiper-meable membrane are discussed. As there is little to no reference work done on unconsolidated sediments the results are compared with shales.

Chapter 6 reports the fate of polycyclic aromatic hydrocarbons in the samples of harbour sludge when subjected to a small advective flux. Polycyclic aromatic hydrocarbons are an example of contaminants that may be transported by advection due to osmosis. Their nonionic hydrophobic character permits transport through the barrier that is semipermeable by its charge properties.

The last chapter, Chapter 7, discusses advantages and disadvantages of the instrumentation developed for this study. A synthesis is given of the experimental work and the implications it has on the storage of harbour sludge in depots. The applicability of the models to 'messy', natural samples is discussed.

full text of the thesis

Ph.D.-thesis is no longer available in its printed form as I have no copies left, you have to do with the pdf-files. The pdf-files are also available via the
download page.


The Ph.D.-study resulted, besides the thesis, in the following publications:
  • Th.J.S. Keijzer & J.P.G. Loch (2001). Chemical osmosis in compacted dredging sludge, Journal of the Soil Science Society of America 65, 1045-1055. — available as pdf-file (203 kb) (article)
  • J.P.G. Loch & Th.J.S. Keijzer (1999). Chemical osmosis in dredging sludge in: 91th Annual Meeting of the Soil Science Society of America, Salt Lake City, USA, p. 339. (abstract)
  • Th.J.S. Keijzer, P.J. Kleingeld & J.P.G. Loch (1999). Chemical osmosis in compacted clayey material and the prediction of water transport, Engineering Geology, 53, 151-159. — see doi:10.1016/S0013-7952(99)00028-9Icon_External_Link or pdf-file (216 kb) (article)
  • Th.J.S. Keijzer, P.J. Kleingeld & J.P.G. Loch (1997). Chemical osmosis in compacted clayey material and the prediction of water transport in: Geoenvironmental Engineering. Contaminated Ground: Fate of pollutants and remediation (eds. R.N. Yong & H.R. Thomas), Cardiff, Wales, p. 199-204. — available as pdf-file (108 kb) (abstract)
  • Th.J.S. Keijzer & J.P.G. Loch (1997). Osmotically induced water transport through compacted clayey material in: Conference on Interfaces Against Pollution 1997, Wageningen, the Netherlands, p. 130. — available as pdf-file (6 kb) (abstract)
  • J.P.G. Loch & Th.J.S. Keijzer (1996). Chemical osmosis in contaminated clayey materials in: Journal of Conference Abstracts V.M. Goldschmidt Conference, Heidelberg, Germany, p. 367. (abstract)
  • Th.J.S. Keijzer, J.P.G. Loch & F.A. Weststrate (1994). Experimentele bepaling van chemische osmose in kleiige monsters, Universiteit Utrecht, 57 pp. (in Dutch, report)