Physico-chemical and Thermal behavior of Barind Red Clay from Naogaon, Bangladesh: Implications for Ceramic Industries as a Raw Material

Abstract

This study evaluates the potential industrial suitability of red clay from Sapahar Upazila, Naogaon District, Bangladesh. Comprehensive laboratory tests were conducted, including Atterberg limits, grain size analysis, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and thermogravimetric analysis (TG), to investigate the mineralogical, geological, ceramic, and plastic properties of the samples. The mineralogical analysis reveals that the red clay is composed of illite, kaolinite, albite, anorthite, smectite, mica, and quartz. Chemically, the red clay primarily consists of SiO₂ (55.06–57.73%), followed by Al₂O₃ (16.96–18.89%), Fe₂O₃ (8.29–10.15%), K₂O (2.98–3.42%), TiO2 (1.28–1.38%), trace amounts of other oxides (< 1%) and LOI (8.34%-9.99%). TG/DSC curve trends indicate the stability of red clay beyond 1000°C. Firing experiments conducted at 800°C, 900°C, 1000°C, and 1100°C show changes in firing shrinkage (0.05–1.15%), water absorption (7.66–4.31%), apparent porosity (13.58–9.53%), bulk density (1.7 g/cm³–2.21 g/cm³), and unconfined compressive strength (7.22–1.35 MPa). These findings suggest that the local red clay is suitable for manufacturing vitrified and semi-vitrified ceramic tiles, indicating its potential for industrial applications in the ceramics sector.