1,720,979 research outputs found
Preparation and Characterization of Composite Anthill-Chicken Eggshell Adsorbent: Optimization Study on Heavy Metals Adsorption Using Response Surface Methodology
No full textReview on Prevalence of Waterborne Diseases in Nigeria
No full textThe problems associated with drinking water encountered in some parts of Nigeria have created a public Health concern. Governments that are unserious about provision of safe drinking water are liable to experience outbreak of waterborne diseases. Nigeria is one of the countries suffering from the crippling burden of water related diseases. The common diseases of drinking water in Nigeria include Cholera, Dracunculiasis, Hepatitis, Typhoid and Filariasis. In this research study, the profile of water related diseases in Nigeria from 2002-2008 was considered. This work was carried out with a view to assessing the successes recorded and problem encountered by governments: analyze the trend and spartial dimension of these diseases in Nigeria and to suggest necessary recommendations for proper management. Data were got from National Bureau of Statistics, Abuja (NBS). Microsoft excel was employed in analyzing the data. From the result obtained, it was revealed that typhoid ranked the highest, followed by cholera, hepatitis and dracucunliasis. Based on the problems facing Nigeria, it is strongly recommended that ministries of water resources and environment at both state and federal levels take the following steps: organize sensitization programmes addressing waterborne diseases, work closely with world health organization (WHO) and other health bodies to provide direct necessary support to Nigerian government and mitigate unsafe drinking water and waterborne diseases in Nigeria
Characterization of alkaline modified anthill and investigation of its catalytic behaviour in transesterification of Chrysophyllum albidium seed oil
No full textThis study focused on the synthesis of fatty acid methyl esters (FAME) from Chrysophyllum albidium seed oil (CASO) via transesterification process using alkaline modified anthill as heterogeneous catalyst. The prepared catalyst was characterized by Brunauer-Emmett-Teller (BET) surface area analysis, basicity, scanning electron microscopic-energy dispersive X-ray (SEM-EDX), Fourier transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) and X-ray diffraction (XRD), and the reusability of the catalyst was tested to check its stability. Central composite design (CCD) was used for optimization of transesterification of CASO with methanol. The variables considered were the reaction temperature (50–80 °C), catalyst loading (2–4 wt%) and methanol/CASO molar ratio (6:1–10:1). Predicted values of FAME yield were found to be in agreement with the observed values obtained (R2 = 0.9650 and Adj-R2 = 0.9335). The results of optimization studies revealed that maximum FAME yield was obtained at the optimum conditions of 64.82 °C reaction temperature, 3 wt% catalyst loading and 8:1 methanol/CASO molar ratio during reaction time of 2 h. The catalyst lost its activity after three reaction cycles. Keywords: Anthill, Catalyst, Chrysophyllum albidium seed oil, Heterogeneous reaction, Transesterificatio
Parametric optimization of solvent extraction of Jatropha curcas seed oil using design of experiment and its quality characterization
No full textThe present study investigated the individual and combined effects of extraction temperature (50–70 °C), particle size (0.6–1.0 mm), and solvent/solid ratio (8:1–10:1 mL/g) on the yield of Jatropha curcas seed oil (JCSO) using n-hexane as extraction solvent. Central composite design was used for optimization of the oil extraction process. The functional groups, purity and chemical content and fatty acid profile of the extracted JCSO were determined by FTIR, NMR, and GC-FID analyses, respectively. Optimization results showed good agreement between predicted and experimental values of oil yield with a high coefficient of determination (R2 = 0.9021 and Adj-R2 = 0.8140). The optimum extraction temperature, particle size, and solvent/solid ratio to achieve maximum oil yield of 56.69 wt.% were 69.67 °C, 0.63 mm, and 9.98:1 mL/g, respectively. The properties of the extracted JCSO compared favourably well with those reported in the literature. The extracted JCSO was made up of aliphatic, carbonyl, esters, unsaturated alkenes, glyceryl, and carboxylic groups, as revealed by the FTIR and NMR analyses. The extracted oil was more of unsaturated fatty acids with the dominance of oleic (53.27%) and linoleic (19.94%) acids
Alumina-Supported Nickel Oxide as Oxygen Carrier in a Chemical Looping Combustion of Hydrocarbon Fuel
Get PDFChemical looping combustion has been identified as a promising combustion process with inherent capturing of carbon dioxide and electricity generation. This novel technology involves the use of solid material capable of supplying oxygen and facilitating the combustion operation in absence of nitrogen diluted air. This solid material is known as oxygen carrier. This study attempts to review the preparation and characterization of nickel- based oxygen carrier supported on alumina (NiO/Al2O3). Its Preparation involves evaluation or modification of support, contacting the support with impregnating solution, removal of excess solution, drying, calcination and activation. Hence, the characterizations of oxygen carrier are based on its properties (physical and chemical). The development of kinetic model to describe the reduction-oxidation reaction of active component of oxygen carrier (NiO) with hydrocarbon fuel (CH4) and air is also put into consideration. Several assumptions are made to simplify the model. The nucleation and nuclei growth model is used to analyze the kinetic parameters contained in the model. The activation energy (E) could be determined using iso-conversion method based on the assumption that the rate of reaction at a constant extent of reaction, is only a function of the temperature. Also, numerical, analytical or graphical solution of rate expression would yield kinetic constant (k)
Experimental investigation of adsorption capacity of anthill in the removal of heavy metals from aqueous solution
No full textOptimization and characterization of crude oil contaminated soil bioremediation using bacteria isolates:Plant growth effect
No full textThis study investigated the effect of soil pH, nitrogen-phosphorus ratio, crude oil concentration and bacteria isolates (from petroleum hydrocarbon-contaminated soil) concentration on the optimization of crude oil-contaminated soil bioremediation using central composite design. The responses were total petroleum hydrocarbons (TPH) and plant growth. A 60-day pot experiment was conducted. Natural soil, crude oil-contaminated soil and bioremediated soil were characterized by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), energy dispersive X-ray (EDX), carbon-hydrogen-nitrogen (CHN) analyser and gas chromatograph-mass spectroscopy (GC–MS). Optimum predicted values were 4.69, 7.68 g/g, 250.05 mL/L and 568.35 cell/g for soil pH, nitrogen-phosphorus ratio, crude oil concentration and bacteria isolates concentration respectively. Experimental run at optimum point affirmed the accuracy of the developed models. Characterization revealed contamination of natural soil by hydrocarbons and their biodegradation via the action of active functional groups present in bacteria isolates. Conclusively, the bacteria isolates could be applied as effective scavenger for hydrocarbon biodegradation in crude oil contaminated soil
ADSORPTION OF CATIONIC DYE FROM AQUEOUS SOLUTION USING COMPOSITE CHICKEN EGGSHELL - ANTHILL CLAY: OPTIMIZATION OF ADSORBENT PREPARATION CONDITIONS
Get PDFA composite adsorbent was prepared from anthill and eggshell mixture, using an incipient wetness impregnation method and it was used for an adsorption of cationic dye (methylene blue, MB) from an aqueous solution. The effects of three preparation parameters including calcination temperature, calcination time and mixing ratio of eggshell to anthill on the MB uptake were investigated using the central composite design (CCD) of response surface methodology (RSM). A quadratic model was developed to predict the response with a high accuracy. The optimal adsorbent sample was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and X-ray fluorescence (XRF) spectroscopy. The obtained results revealed that the calcination temperature significantly affected the MB adsorption. The optimum MB uptake of 23.87 mg/g was achieved under the optimum conditions including a calcination temperature of 823.45 °C, calcination time of 3.54 h and eggshell/anthill mixing ratio of 1.89:1. A detailed characterization of an optimal adsorbent sample confirmed the presence of pores, active functional groups and various molecular adsorption sites on its surface. Equilibrium adsorption isotherms and kinetics were also studied and it was revealed that the isotherms and kinetics data fitted well to the Freundlich model and pseudo-second-order kinetics model, respectively
Equilibrium, Kinetic and Thermodynamic Studies of the Adsorption of Heavy Metals from Aqueous Solution by Thermally Treated Quail Eggshell
No full textBiodiesel production from transesterified waste cooking oil by zinc-modified anthill catalyst: Parametric optimization and biodiesel properties improvement
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