SYNTHESIS AND CHARACTERIZATION OF PURE SILICA POWDER FROM A K-FELDSPAR SILICATE ORE FOR INDUSTRIAL VALUE ADDITION
Abstract
Nigeria is one of the African countries endowed with abundant varieties of solid mineral resources. Despite huge mineral abundance in all States of the Federation, these resources to boost the country’s economy, aid industrialization and revenue generation has
been far less utilized. Thus, the utilization of a Nigerian k-feldspar ore containing an admixture of orthoclase (KAlSiO8 : 96-740-9031), albite (AlSiO8 : 96-940-0741) and quartz (SiO2 : 96-900-9667) impurities to produce pure silica powder (PSP) was investigated using
roast-leaching and co-precipitation method. During leaching, parameters such as leachant concentration, effect of particle size and reaction temperature on the synthesis yield were accordingly examined. At optimal leaching conditions (2.0 mol/L NaOH, 90°C), 87% of the initial 10g/L ore reacted within 120 minutes. The un-reacted product (~13.0%) analyzed by XRD was found to contain siliceous impurities which could serve as a valuable by-product for some defined industries. The leachate at optimal leaching was accordingly co-precipitated using concentrated H2SO4 to obtain pure silica powder (PSP) of industrial value.
Keywords
Silica,K-feldspar,Leachant,Optimal leaching,Orthoclase,Kinetics
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