Kaolinite structural modifications induced by mechanical activation

This study presents novel characterisation techniques to evaluate the effects of mechanical activation (MA) on the kaolinite structure. MA was achieved with a planetary ball mill at various times and rotation speeds to get different activation degrees. A thermal activation was performed for comparis...

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Detalles Bibliográficos
Autores: Mañosa Bover, Jofre, Calvo de la Rosa, Jaume, Silvello, A. (Alessio), Maldonado Alameda, Alex, Chimenos Ribera, Josep Ma.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/198963
Acceso en línea:https://hdl.handle.net/2445/198963
Access Level:acceso abierto
Palabra clave:Caolí
Difracció de raigs X
Espectroscòpia infraroja
Kaolin
X-rays diffraction
Infrared spectroscopy
Descripción
Sumario:This study presents novel characterisation techniques to evaluate the effects of mechanical activation (MA) on the kaolinite structure. MA was achieved with a planetary ball mill at various times and rotation speeds to get different activation degrees. A thermal activation was performed for comparison purposes. The results of X-ray diffraction and selective area electron diffraction demonstrated that the kaolinite content was significantly reduced as the amorphous phase increased. Illite, K-feldspars, and quartz impurities were extensively modified as well. The morphology of kaolinite particles is altered. Furthermore, the mechanical treatments significantly affected the hydroxyls, losing bonding strength with the structure, as stated with 1H nuclear magnetic resonance. Thermogravimetric analysis and infrared spectroscopy also revealed that water molecules could be formed due to the reaction of hydroxyls between them or with the atmosphere. This work improves the comprehension of MA on kaolin by clearly confirming with new techniques that the mechanical treatments distort the kaolinite structure.