Physicochemical, Morphological, and Thermal Characterization of Selected Clay Samples from Southern Libya
DOI:
https://doi.org/10.37375/susj.v16i1.4138Keywords:
clay characterization, southern Libya, physicochemical properties, Munsell color, drying curve, shrinkageAbstract
Eight clay samples collected from southern Libya were characterized using descriptive observation, light-microscope examination, Munsell color estimation, and selected physicochemical tests. The samples showed clear differences in color, texture, particle appearance, moisture content, pH, electrical conductivity, particle density, shrinkage behavior, exchangeable cations, and water-extractable phosphorus. Moisture contents were low in all samples, ranging from 0.09-1.06%, which indicates that the samples were close to air-dry condition before testing. The pH values ranged from 5.49-7.31, indicating slightly acidic to near-neutral conditions. Electrical conductivity ranged from 0.20-5.27 dS.m−1, with Sample 2 showing the highest value, most likely because of a higher concentration of soluble salts. Particle density ranged from 1.88-2.31 g.cm−3, while the shrinkage/expansion coefficient ranged from 1.81-6.59%. Water-extractable phosphorus varied widely from 0.97-87.6 mg.Kg−1, indicating substantial differences in soluble phosphorus among the samples. Drying-curve data showed limited mass loss below 200 °C, followed by more pronounced losses at higher temperatures. By 800 °C, the total mass loss ranged from approximately 8.8-15.7%, with Sample 8 showing the highest total loss. These results provide an initial basis for evaluating southern Libyan clay as a local natural resource, but further mineralogical and application-specific testing is required before industrial or environmental use can be recommendedReferences
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