Browsing by Author "Adekola, F.A"
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Item BLEACHING OF A NIGERIAN KAOLIN BY OXALIC ACID LEACHING(University of Chemical Technology and Metallurgy, 2015) Baba, A.A; Masobalaje, M.A; Ibrahim, A.S; Girigisu, S; Eletta, O.A; Fasakin, I.A; Aluko, I; Adekola, F.AThe level of improvement of whiteness of Egbeda (Nigeria) kaolin ore by oxalic acid leaching was investigated. The effects of acid concentration, reaction temperature and particle size on the extent of the ore dissolution were examined. The results of the leaching investigation on the improvement of the ore whiteness assessment were found to increase with increasing acid concentration, reaction temperature and decreasing particle size. At optimal leaching (0.5 mol L-1 H2C2O4, 85°C, 120 minutes) with moderate stirring, the dissolution reached 79.9 %, when total iron removal was achieved as evidenced from the EDXRF and EDS analyses. The dissolution curves were analyzed and found to conform to the surface chemical reaction, and the calculated activation energy of 41.34 kJ mol-1 supported the proposed model. These results are also corroborated by the output of the Post-Hoc test by Duncan Univariate Anova Analysis using SPSS 7.1. Finally, oxalic acid proved to be effective for treating the Egbeda (Nigeria) kaolin ore for total iron impurities removal and improving the ore whiteness for possible industrial utilities. Keywords: kaolin ore, Nigeria, leaching, oxalic acid, bleaching, iron impurities removal.Item Determination of concentration of heavy metals in two common fish species from Asa River, Ilorin, Nigeria(Published by, Taylor and Francis Group, Germany., 2003) Eletta, O.A; Adekola, F.A; Omotosho, J.SConcentrations of some heavy metals in Tilapia zilli (Tilapia) and Synodontis membrane (Catfish), the two common fishes from Asa River Ilorin, Nigeria have been determined. Manganese, zinc, iron, and lead, were present at appreciable concentrations in the tissues of the two species while cadmium, mercury, and nickel, were found to be less than 0.01 ppm. Concentrations of metals were highest downstream than at upstream locations. Mean concentrations of Mn in Tilapia, ranged between 0.56 ppm at the upstream end and 2.69 mg/kg of fresh weight at the downstream end. Pb, Zn, and Cr ranged between 4.05 and 5.59 mg/kg of fresh weight, 0.09 and 1.16 ppm, 5.62 and 11.15 ppm, and 0.09 and 0.13 ppm respectively. In the Catfish, Mn, Fe, Zn, and Cr ranged between 0.62 and 0.78 ppm, 3.79 and 8.79 ppm, 0.78 and 1.57 ppm, 7.30 and 15.15, and 0.23 and 0.35 ppm respectively. Heavy metals except lead did not pose any health risks in human since the calculated probable amounts being ingested by an average adult (50 kg average weight) per day were lower than WHO maximum recommended value of intake. However, the level of lead was higher than WHO limit and this could render inedible the fishes from this catchment river.Item Mineral Characterization of Yombo-Fitta - An African Natural Hair Dye(2011) Adebayo, G.B.; Adekola, F.A; Olatunji, G.A.Mineral contents of an African hair dye were investigated. Some physiochemical properties such as solubility, pH, ash and organic content were first carried out. Combinations of XRF, XRD, SEM, IR, and UV-VISIBLE spectroscopic techniques were employed in the investigation. The dye was found to dissolve in all the ten aqueous and nonaqueous media used. The pH of the aqueous solution was found to be 8.6. Ash and organic contents of the raw dye were found to be 51% and 49% respectively. The XRF revealed that the dye contains twenty elements which include K, Ca, Ti, V, Cr, Zn, Mn, Fe, Co, Ni, Cu, As, Nb, Zr, Rb, Sr, Y, Mo and Br, with concentrations ranging from major to ultra-trace levels. The XRD also showed that the sample contains about forty six mineral phases which include both inorganic and organic components. The optical microscopic investigation gave indication that the dye was likely to be of the marine origin. The infrared (IR) measurements indicated that the sample contained functional groups such as C=O, C=C, C-C, CN, aromatic ring and metal-carbon chelate rings. The UV-VIS spectra show that the dye absorbed in the visible region with λmax of the aqueous solution being 464.0 nm.Item Physico – mechanical assessment of plaster of Paris bandage produced from locally sourced materials(Materials Research Society of India and Indian National Science Academy (Springer)., 2019) Adekola, F.A; Olosho, A.I; Adeleke, A.A; Eletta, O.A; Agaja, S.BDespite the abundance of gypsum and other material needed for the production of plaster of Paris (POP) in the country, Nigeria relies 1 heavily on the importation of orthopaedic POP bandage. Therefore, the present study aimed at producing POP bandage (LPOP) from locally sourced pure gypsum and cassava starch. Physico-chemical parameters such as amylose content, amylopectin content, water absorption capacity (WAC), swelling capacity (SC) and browning-charring temperature (BCT) were obtained for the starch binder. A slurry of pure gypsum powder and 2% gelatinized starch binder was impregnated on cotton gauze and cured in an oven at 180◦C for an hour to produce the LPOP. A comparative mechanical test was carried out on the LPOP and a POP bandage (CPOP) acquired from the market using a universal testing machine. The results showed that starch contains 9.06 mg/100 g amylose and 24.1 mg/100 g amylopectin which implied that it has a good binding property. The SC,WAC and BCT were evaluated to be 69.79%, 81.94% and 190◦C, respectively. The yielding tensile force for LPOP and CPOP are 148 and 460 N respectively. The horizontal compressive strength of the LPOP and CPOP are 1712 and 1595 N while the vertical compressive strengths are 1070 and 623 N respectively. These results show that the LPOP produced from locally sourced materials compete favourably in terms of mechanical properties with POP bandage in the market. Thus, based on its strength, it is recommended for orthopaedic casting.Item A study of heavy metal pollution of Asa River, Ilorin ,Nigeria: Trace metal monitoring and geochemistry(Springer, 2007) Adekola, F.A; Eletta, O.AChemical and mineralogical characterization of sediments collected from seven different locations along Asa River in Ilorin, Nigeria have been carried out. The total concentration of Mn, Cr, Fe, Zn and Cu were monitored using Total Reflection X-ray Fluorescence (TXRF). The range of concentration of these metals were: Mn (179.9-469.4, Fe (1998.4-4420.4) Cr (3.0-11.3), Zn (26.6-147.6), Cu (1.9-13.3) mg kg(-1). The mineralogical composition was determined using X-ray diffraction (XRD) method and this was complemented with the Infrared Spectroscopy. It was found that the sediments of Asa River had predominantly quartz, and goethite was present in five of the seven locations. Chromite (FeCr(3)O(4)) and pyrite (FeS) were also identified at some locations along the River. Higher enrichment factors were calculated for Zn, Cr, Mn, and Fe in the sediment indicating anthropogenic source of contamination. Pyrite was prominent at a location receiving effluent from a detergent industry and near a refuse dumpsite.