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USGS · 70010916

Kaolinite synthesis at 25°C

J.D. Hem·Carol J. Lind
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Abstract

The addition of quercetin, an organic flavone (C 15 H 10 O 7 ), to aqueous solutions containing silica and aluminum and adjusted to final p H's from 6.5 to 8.5 produced a 1 : 1 alumninosilicate precipitate which, after 6 to 16 months of aging in solution at 25°C, contained as much as 5 percent well-formed kaolinite plates. Similar solutions containing no organic material produced relatively amorphous precipitates with the same composition and stability (standard free energy of formation = -897±1 kilocalories per mole) but with substantially smaller amounts of crystaline material even after 2 years of aging.

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J.D. Hem, Carol J. Lind. 1974. Kaolinite synthesis at 25°C. https://doi.org/10.1126/science.184.4142.1171

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