Direct Investigation of the Fate of NAPL Contaminations in a Hydrating Cement Matrix by Means of Magnetic Resonance Techniques

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• 作者：Nikolaus Nestle ; Petrik Galvosas ; Christian Zimmermann ; Frank Stallmach ; and Jö ; rg Kä ; rger
• 刊名：Environmental Science & Technology
• 出版年：2004
• 出版时间：February 1, 2004
• 年：2004
• 卷：38
• 期：3
• 页码：880 - 885
• 全文大小：122K
• 年卷期：v.38,no.3(February 1, 2004)
• ISSN：1520-5851

文摘

The behavior of nonwatery solvent phases in hydratingcement pastes is of great interest in the context of solidificationof wastes containing such phases. In a recent study, theinfluence of various solvents on the hydration kinetics ofcement was studied. In this paper, we present resultson the changes in the behavior of the solvent phasesthemselves during setting of the cement pastes. The methodsused in the studies were NMR relaxometry and pulsedfield gradient (PFG) NMR diffusometry. To study selectivelythe behavior of the non-aqueous-phase liquid (NAPL)phases, heavy water was used in the preparation of thecement pastes. The experimental results are in goodagreement with the observations from earlier studiesconcerning the behavior of toluene in hydrating cement.For aliphatic solvents (cyclooctane, n-hexanol), indicationsfor surprisingly large networks of connected droplets inthe cement matrices are found.