Carbon NMR used in probing the exchange of ethanol with water in water-saturated cement pastes.
The exchange of water by ethanol in two water-saturated cement pastes has been investigated by carbon NMR. The two cement pastes differed only in their thermal history. The diffusion of ethanol into the cement paste was shown to be described by Fickian diffusion, assuming one-dimensional diffusion under perfect sink boundary conditions. The diffusion coefficients were calculated to be (1.28 +/- 0.14) 10(-7) cm2/s for the virgin cement sample and (4.38 +/- 0.57) 10(-7) m2/s for the preheated cement sample (preheated at 105 degrees C for 12 h), respectively. The measurements indicate an extensive exchange between water and ethanol.
Hansen
E W
EW
SINTEF, Oslo, Norway.
Gran
H C
HC
D003252:Construction Materials; D004058:Diffusion; D000431:Ethanol; D009682:Magnetic Resonance Spectroscopy; D014867:Water
D014867:Water; D000431:Ethanol