Physico-Chemical Characteristics And Industrial Potentials Of Lepidolite From Ijero-Aramoko Pegmatite Field, Southwestern Nigeria.
Akinola, Oluwatoyin O, Okunlola, Olugbenga A, Obasi , Romanus A.
Index Terms: Enriched-lithium, industrial potentials. Ijero-Aramoko Ore, pegmatite.
Abstract: Physico-chemical characteristics and industrial potentials of lepidolites from Ijero-Aramoko pegmatite fields were investigated . Systematic mapping indicates that the lepidolite is associated with steeply inclined pegmatite intruded into the basement rocks of gneisses and schistose assemblages that are in places pulsed with isolated Pan-African granite. The lepidolite has a layered structure, a perfect unidirectional cleavage and equigranular texture. Thirty lepidolite samples were collected from the pegmatite fields and anaylsed using the Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) method .in the Activation Laboratories, Ontario Canada. The results of the analysis indicate that the silica (SiO2) content in the lepidolite ranges between 49.43 and 50.16% in Oke-Asa, 49.49-50.43% in Oke-IgboAba and 57.87-57.81% in Ijero-Ekiti mineralized areas . Average Al2O3 contents in these three areas are 27.83%, 23.02% and 28.34% respectively. In the same trend, K2O has the following average values 10.06%, 9.41%, and 5.86% while MgO, CaO and TiO2 values are generally less than 0.3% in all the samples. Trace element composition reveals higher Li, Be, Cs and Rb contents relative to Ta, Nb and Sn. The average Li values of 1859 ppm, 1778 ppm, and 1656 ppm are recorded for Oke-Asa, Oke-Igbo Aba and Ijero Ekiti respectively. The high contents of SiO2, Al2O3, and K2O as well as the unusual amount of lithium and microcline reveal the general geochemical characteristics of the lepidolite on which its industrial applications are based. Lithium compounds form sources of raw materials in the pharmaceuticals and in the making of energy lithium batteries and serves as an alloy of aluminium, magnesium and zinc.The physical tests reveal high specific Gravity (2.69-2.80; ca. 2.74), compressive strength (45.84-50.14; ca. 48.93) N/mm2, wet density (2.30 to 2.65; ca. 2.39) g/cm3, and less water absorption capacity (0.21 to 0.35; ca.0.26) %, . These physical characteristics make the lepidolites suitable for use in various industrial areas where lithium compounds are employed.
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