Document Type : Research Paper
Abstract
The escalating global water crisis necessitates sustainable and cost-effective solutions for brackish water purification. This study characterises an indigenous clay sample to evaluate its potential as an adsorbent and a multi-functional bio-filter for brackish water treatment. An advanced analytical technique was employed, including X-ray Diffraction (XRD), X-ray Fluorescence (XRF) elemental analysis, Fourier-transform infrared spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET) surface area and porosity measurements. The XRD results showed that the clay examined is a complex mineralogical assemblage, predominantly composed of quartz (49.0%), orthoclase (16.4%), chlorite (14.0%), muscovite (10.0%), albite (9.3%), and illite (1.36%). Similarly, XRF elemental analysis corroborated a silicate rich composition (46.3% SiO2, 38.2% Al2O3). In addition, FTIR spectroscopy provided a chemical fingerprint, confirming the silicate framework, indicating the likely presence of palygorskite as well as organic matter, adsorbed water, and potential iron oxyhydroxides and gypsum. Essentially, BET analysis demonstrated an exceptionally high multipoint surface area of 389.4 m²/g, coupled with a dual-scale porous structure dominated by micropores and small mesopores of 1.8-6.5nm average pore diameters and suggests a Type IV isotherm with an H1 hysteresis loop. These properties illustrate that indigenous clay is excellent for biofiltration, high in quartz and minerals supporting adsorption and ion exchange capabilities. The surface area is suitable for creating an optimal environment for microbial colonisation and biofilm development, thereby enhancing the biological degradation of pollutants. Overall, the clay under consideration is highly effective at removing suspended solids, heavy metals, and biodegradable pollutants.
