Kaolin from Acoculco (Puebla, Mexico) as raw material: Mineralogical and thermal characterization

Abstract

A B S T R AC T : The present study determined the mineralogy and thermal properties of kaolin from Acoculco (Puebla), at the eastern Trans-Mexican Volcanic Belt and compared it with the nearby deposits of Agua Blanca (Hidalgo) and Huayacocotla (Veracruz). The mineralogy of the kaolins was determined by X-ray diffraction, infrared spectroscopy and scanning electron microscopy. Thermal behaviour was studied by differential thermal analysis, dilatometry and hot-stage microscopy. The Acoculco deposit is composed mainly of kaolinite and SiO 2 minerals. In the case of Agua Blanca and Huayacocotla, alunite is abundant in places and minor anatase is also present locally. The Acoculco kaolins are Fe-poor and relatively rich in some potentially toxic elements (Zr, Sb, Pb). They undergo a relatively small amount of shrinkage (∼3-4 vol.%), during firing at 20-1300°C and cooling down to 20°C, except when >10 wt.% alunite is present. These kaolins are a suitable raw material for the ceramics industry. Other applications (pharmaceuticals, cosmetics) would require an enrichment process to eliminate impurities such as Fe oxides.

Mineralogical and Thermal Characterization of Kaolinitic Clays from Terra Alta (Catalonia, Spain)

“…Most of the analyzed samples from the outcrops can be classified as silico-aluminous clays. This chemical composition is similar to other kaolins with applications in the ceramics industry [25][26][27][28][29][30][31] (Figure 3). [25], Turkey I [26], Turkey II [27], Tunisia I [28], Tunisia II [29], Castellón (Spain) [30], Western Portugal [31].…”

“…This chemical composition is similar to other kaolins with applications in the ceramics industry [25][26][27][28][29][30][31] (Figure 3). [25], Turkey I [26], Turkey II [27], Tunisia I [28], Tunisia II [29], Castellón (Spain) [30], Western Portugal [31]. [25], Turkey I [26], Turkey II [27], Tunisia I [28], Tunisia II [29], Castellón (Spain) [30], Western Portugal [31].…”

“…Scanning electron microscope observations show that the Terra Alta clays exhibit platy regular lamellar hexagonal flakes of kaolinite, often grouped in stacks ( Figure 6). Tubular crystals were not observed, which confirms the absence of halloysite [25,50]. Scanning electron microscope observations show that the Terra Alta clays exhibit platy regular lamellar hexagonal flakes of kaolinite, often grouped in stacks ( Figure 6).…”

“…[25], Turkey I [26], Turkey II [27], Tunisia I [28], Tunisia II [29], Castellón (Spain) [30], Western Portugal [31]. [25], Turkey I [26], Turkey II [27], Tunisia I [28], Tunisia II [29], Castellón (Spain) [30], Western Portugal [31].…”

7th Mid European Clay Conference, Dresden, Germany, September 2014: Overview of the Clay Mineralogical Studies

“…Finally, Garcia-Valles et al (2015) investigated the mineralogy and thermal properties of kaolin from Mexican deposits from Acoculco (Puebla), Agua Blanca (Hidalgo) and Huayacocotla (Veracruz) at the eastern Trans-Mexican Volcanic Belt, for their suitability as raw material for the ceramic industry.…”