Abstract
The objective of this study was to characterize and explore wastes of two clays (B and C, collected at different soil layers) and argillite, generated during the extraction of gypsum in the municipality of Araripina-Brazil, for application in red ceramics. Ceramic samples were prepared using residual clays with additions of 40%, 50% and 80% of argillite, compression-molded, dried at 110 ºC and sintered at 850, 950 and 1050 ºC for 2 h. Then, water absorption, linear retraction, loss on ignition, apparent porosity, apparent specific gravity, three-point flexural strength and microstructure of fracture surface were evaluated. The use of residual clays with a maximum content of 50% of argillite showed feasible in red ceramics. The best results were obtained in the ceramic bodies with clay B (containing montmorillonite) with addition of 40% and 50% of argillite in relation to clay C.
Keywords:
clay; Araripina; argillite; gypsum; red ceramics
