Croatica Chemica Acta, Vol. 70 No. 2, 1997.
Original scientific paper
FT-IR and Mossbauer Study of Corrosion of Steel in Tap and Mineral Water
Svetozar Musić
; Ruder Bošković Institute; P. O. Box 1016, 10001 Zagreb, Croatia
Đurđica Dragčević
; Ruder Bošković Institute; P. O. Box 1016, 10001 Zagreb, Croatia
Ilona Czako-Nagy
; Department of Nuclear Chemistry, Eotoos-Lorand University, p. O.Box 32, 1518 Budapest, Hungary
Stanko Popović
; Ruder Bošković Institute; P. O. Box 1016, 10001 Zagreb, Croatia
Abstract
The influence of carbonates on the process of corrosion of steel in
aqueous media has been studied. The corrosion of steel in tap
water and mineral water of three different chemical compositions (all
for human use) was monitored for up to 6 months. Rust samples were
analyzed using Fourier transform infrared (FT-IR) spectroscopy and
57 Fe Mossbauer spectroscopy. Some selected samples were also analyzed by X-ray powder diffraction (XRD).It was shown that the concentration of carbonates plays an important role in the corrosion of steel in aqueous media, both during short (days), and long times
(months) of corrosion. For short times of corrosion in the presence of
a high content of carbonates, the rust was found amorphous for XRD.
It was proved that "'(-FeOOHwas absent in amorphous rust. The possible presence of ferrihydrite in this amorphous fraction is discussed taking into account the FT-IR and Mossbauer spectroscopic results. At a very high concentration of carbonates, after 6 month of corrosion,'(-FeOOHwas not found in the rust. Formation of a-FeOOH and Fe304 in corrosion products was also monitored. It was suggested
that, in the very early stages of corrosion, carbonates can be structurally incorporated in the rust in the form of hydroxycarbonates,
while in the later stages, they can modify the phase transformation
by the mechanism of specific adsorption.
Keywords
Hrčak ID:
176967
URI
Publication date:
1.5.1997.
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