Potentiality of new dark clay-rich materials for porous ceramic applications in Ouled Sidi Ali Ben Youssef Area (Coastal Meseta, Morocco)

Abstract

Potential use of raw clayey deposits from El Jadida, Morocco, in the manufacture of traditional ceramic products has been evaluated through a careful sampling and an in-depth characterization of the outcropping features around Ouled Sidi Ali Ben Youssef area (El Jadida city). We collected six representative clay-rich materials (C1–C6) for subsequent analyses by several spectroscopic and mineralogical techniques including physico-chemical, mineralogical, and thermal analyses. Our results revealed high amounts of oxides, mainly SiO2, Al2O3, Fe2O3, CaO and MgO. Those ferruginous clays were found suitable for dark ceramic bodies. Further mineralogical examination confirmed low to medium contents of clay minerals, but subordinated by quartz, calcite, dolomite and plagioclase as the main nonclay minerals. Ternary diagram plots indicated that the studied clays were suitable for structural clay products and clay roofing tiles. C5 sample exhibited the best physico-chemical and mineralogical properties due to its illitic nature (64%), low quartz content (28%), high plasticity index (32) and lower loss on ignition (10.84%). Therefore, C5 clayey sample was selected as a potential candidate to be mixed with expanded perlite (EP) for the production of insulating ceramics. Specimen were prepared from the new mixture (i.e., C5 and EP) by pressing and firing at 1100°C. The obtained ceramic bodies were ascertained by addressing their bulk density, water absorption, shrinkage, bending strength, thermal conductivity, structural and mineralogical properties.