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El carbonato inhibe la cristalización del hidróxido de aluminio en la bauxita
Science (New York, N.Y.)
|January 26, 1979
Resumen
El ion carbonato inhibe significativamente la cristalización del hidróxido de aluminio, manteniendo los geles amorfos. Este efecto es evidente en los depósitos de bauxita y potencialmente en los antiácidos farmacéuticos.
Área de la Ciencia:
- La geoquímica es la geoquímica.
- La mineralogía es la Mineralogía.
- Ciencias del suelo Ciencias del suelo.
Sus antecedentes:
- Se sabe que los aniones como el nitrato, el cloruro y el sulfato inhiben la cristalización del hidróxido de aluminio.
- El papel significativo del ion carbonato en la preservación de los geles amorfos de hidróxido de aluminio ha sido en gran medida pasado por alto.
Objetivo del estudio:
- Para resaltar el papel pasado por alto de los iones carbonato en la prevención de la cristalización de hidróxido de aluminio.
- Para investigar la influencia del carbonato en la morfología de gibbsite en depósitos de bauxita.
- Para explorar el vínculo potencial entre los geles de hidróxido de aluminio amorfo en los antiácidos y la scarbröite.
Principales métodos:
- Análisis comparativo de los tamaños de grano de gibbsite en depósitos kársticos frente a depósitos de bauxita lateríticos.
- Observación geológica de las ocurrencias de bauxita.
- Revisión de la literatura sobre los geles de hidróxido de aluminio y la scarbröite.
Principales resultados:
- Los iones carbonato mantienen el hidróxido de aluminio en un estado amorfo o poco cristalino.
- La gibbita en las bauxitas kársticas exhibe tamaños de grano más pequeños en comparación con las bauxitas lateríticas, lo que sugiere la inhibición del carbonato.
- Scarbröite (hidroxicarbonato de aluminio cristalino) es raro, pero los geles amorfos en los antiácidos pueden ser formas poco cristalinas de la misma.
- El efecto del sulfato se observa en la disolución de la bauxita y la precipitación relacionada con la oxidación de la pirita.
Conclusiones:
- El ion carbonato juega un papel crítico y subestimado en el estado amorfo del hidróxido de aluminio.
- Comprender la influencia del carbonato es clave para interpretar la formación y las propiedades de la bauxita.
- Los geles de hidróxido de aluminio amorfo, incluidos los de los antiácidos, pueden representar un precursor o una forma poco cristalina de scarbröite.
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