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Welcome to UISpace, The University of Ibadan Institutional Repository. A collection of theses, articles, books, videos, images, lectures, papers, data sets and all types of digital content originating from the University of Ibadan Nigeria. This repository is managed by the Kenneth Dike Library University of Ibadan, Nigeria.
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Investigating the effect of palm kernel shell powder on the rheological and filtration properties of water based mud
(Science Publishing Group, 2024) Akintola, S.A.; James, O.T.; Fatai, O.A.
During drilling operations, the use of drilling fluid plays a critical role, and over time, there has been considerable interest in enhancing drilling fluid characteristics in order to improve performance, reduce costs, and prevent environmental pollution. Deviating from conventional additives, recent studies have explored the use of alternative materials, as drilling fluid additives. In line with this trend, this study focuses on the laboratory investigation of the rheological and filtration properties of water-based drilling fluid treated with Palm Kernel Shell Powder (PKSP) with high viscosity polyanionic cellulose (PAC HV), used as control. To assess the impact of PKSP in water-based mud, experiments were carried out using concentrations spanning from 0.5g to 2.5g, temperatures of 27°C, 40°C, 60°C, and 80°C, and aging of 24, 48, and 72 hours. From the results the plastic viscosity of mud samples treated with PKSP were temperature dependent and also with increasing aging. The addition of PKSP showed improved performance in terms of reducing the filtrate volume as well as the cake thickness with increasing concentration of the additives, and the concentration that gave the best results across all aging duration was 2.5g. The mud weight and pH of all samples remained relatively constant, with no significant changes observed. However, PAC HV showed better results in all the cases of fluid loss and mud cake thickness. It could be attributed to the soluble contents in the PAC HV which increased the viscosity significantly and thus, kept the solid particles in suspension.
The rheological and filtration properties of black seed (Nigella Sativa L.) ester as a base fluid in drilling fluid
(Springer Open, 2024) Olaniyan, D.D.; Akintola, A.S.
The unceasing utilization of diesel oil, the regular base fluid, as the base fluid of drilling mud has brought about severe ecological worries and regulation because of its poisonousness, non-biodegradability, and similarity issues. Notwithstanding, drilling more complex wells is turning out to be progressively significant in satisfying the world’s need for oil and gas, bringing about increased commercial synthetic-based fluid importation. In light of the ecological worries associated with the usage of diesel-based drilling fluids as well as reducing commercial synthetic-based fluid imports, black seed oil (BSO) was utilized to make an ester for a new ecologically safe drilling fluid. This research explored the potential use of black seed ester in formulating oil-based muds with standard additives. It compares its qualities to that of diesel following a thorough mud check on the mud samples to evaluate the rheological properties and the impact of aging at test temperatures of 86°F, 120°F, and 150°F. Fourier transform infrared (FTIR) spectrometry technique affirmed that BSO ester is a natural compound. About the fow properties, the kinematic thickness at 40°C of the biodiesel is 4.31 mm2 /s and is higher than that of petroleum diesel, which is 3.52 mm2 /s. Densities for the ester and diesel oil-based mud tests were 7.9 ppg, 7.8 ppg, 7.3 ppg, and 6.8 ppg, respectively, at 70/30, 75/25, and 80/20, oil–water-proportion (OWR), as utilized in the mud formulation. The prepared mud was aged for 24 h under static conditions to guarantee total hydration. Black seed oil (BSO) ester mud exhibited lower viscosity at all temperatures, aging conditions, and shear rates analyzed, making it more suitable for oil-well drilling fuids when compared with Diesel. BSO being a naturally occurring seed oil could be important for drilling contractors and service companies due to its good ecological acceptability and its applicability.
Valorized rice husk as green corrosion inhibitor for Al 6061 in 1M HCl
(MIM Research Group, 2024) Ikubanni, P.; Oki, M.; Adediran, A.; Akintola, S.A.; Adeleke, A.; Anyim, I.; Adesina, O.; Efenovwe, L.
This study investigated the inhibition characteristics of rice husk (RH) on corrosion of Aluminum 6061 in 1M hydrochloric acid. Gravimetric analysis and Scanning Electron Microscopy (SEM)/ Energy Dispersive X-ray analysis (EDX) as well as electrochemical studies revealed the potency of RH as a good inhibitor of the corrosion of Al 6061 in 1M HCl. Fourier Transform Infrared Spectroscopy (FTIR) indicated that –OH, C=C, and C=O with signals at (3317.19, 2932.9, 2848.2), (1631.8) and (1105.73, 1030.2, 447.15), respectively in RH were the viable active functional groups which adsorbed on the metal surface to effect reduction of corrosion rates. However, literature suggested the presence of amorphous silica in RH which served as a complimentary corrosion inhibitor. The corrosion current density of Al 6061 was reduced to 3.46 × 10−7 A/cm2 at 24 h as against 9.27 × 10−7 A/cm2 at the commencement of the potentiodynamic polarization measurements in inhibited 1M HCl. The control specimens exhibited an average corrosion rate of 3.86 × 10−6 A/cm2 in HCl solution at the start of this investigation as compared to the corrosion rate of 3.46 × 10−7 A/cm2 at 24 h of exposure in 5 mg RH- inhibited HCl. The obtained results gave a corrosion inhibition efficiency of about 90 to 92%.
Scanning and transmission electron microscopy examinations of composite hybrid chromate and chromate phosphate conversion coatings exposed in hot 100% relative humidity environments
(Elsevier B. V., 2023) Ikubanni, P.P.; Oki, M.; Adediran, A.A.; Akintola, S.A.; Adeleke, A.A.
Conversion coatings are sine qua non in the finishing of aluminium alloys. They may be put into service without coating of paints. However, for aesthetics in architectural applications, paint overcoat is common. Chromate phosphate coatings are relatively less toxic than chromate which gained the pride of place until recently. Thus, aluminium specimens coated with hybrid chromate/phosphate conversion coatings have been subjected to 100% relative humidity for 480 h at 313K in comparison to chromate coatings and bare aluminium. Scanning electron microscopy examination revealed that initial dried river bed morphologies on coated specimens were obliterated. The friable outer coatings collapsed into the cracks/environment leaving a relatively smooth surface after exposure. Additionally, transmission electron microscopy of sections before and after exposure revealed similar texture and morphological striations nearly parallel to each other throughout the length of the coatings to the metal/coating interface. These were not disrupted as well as the metal/coating interface which remained relatively smooth with no visible corrosion products after exposure. Thus, the coatings formed effective barrier between the substrate and the relatively harsh environment. From EDS, elemental compositions were the same albeit, spectral intensities remained relatively constant after humidity exposure regimes. The coatings are made up of either Cr, O and Al for chromate and Cr, P, O and Al for chromate/phosphate. At deliberately breached regions, the coatings prevented spread of corrosion and paint delamination over the substrates. On the other hand, bare aluminium was decorated with mounds of hydrated aluminium oxide/hydroxide after exposure as revealed in the SEM/TEM.
Screening of ionic liquids for CO2 capture using data analytics techniques
(UTP Press , Malaysia, 2023) Sulaimon, A.A.; Salang, A.R.T.; Qasim, A.; Akintola, S.A.; Wifred, C.D.A.P.
Carbon dioxide (CO2) is the most prominent greenhouse gas (GHG) present in the atmosphere, making it the most accountable for global warming. CO2 capture is capable of greatly reducing carbon emissions. The current method of CO2 capture by amine-based solvent has drawbacks, such as high demand for energy and intense corrosion, making it a less reliable method. More attention is given to ionic liquids (ILs) for their negligible vapour pressure, low melting point, and high chemical and thermal stability advantage. This study uses data analytics techniques to develop a predictive model for screening ILs for CO2 capture, moving away from the experimental approach, which is burdensome, costly, and less environmental-friendly. Data on the properties and parameters of ILs are collected from COSMO-RS software. CO2 solubility is the function of collected data and developed into 15 models of three different methods: Support Vector Machine (SVM), Neural Networks (NN), and Gaussian Process Regression (GPR). The use of data analytics in this field is new and can provide valuable insight towards CO2 solubility in ILs. The dataset is distributed randomly at 80/20% for training and testing. Each model is evaluated using R-squared and root mean square error (RMSE). The rational Quadratic GPR model shows the lowest RMSE of 0.0002 for training and testing, with R-squared the closest to one. Rational Quadratic GPR is the best model to be used for screening IL for CO2 capture.