20 research outputs found
ADSORPTION OF CATIONIC DYE FROM AQUEOUS SOLUTION USING COMPOSITE CHICKEN EGGSHELL ANTHILL CLAY: OPTIMIZATION OF ADSORBENT PREPARATION CONDITIONS
A 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
Alumina-Supported Nickel Oxide as Oxygen Carrier in a Chemical Looping Combustion of Hydrocarbon Fuel
Chemical 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)
EXTRACTION AND EVALUATION OF OIL FROM GREEN ALGAE CLADOPHORA GLOMERATA BY HEXANE/ETHER MIXTURE
The overall aim of this study was to grow green algae Cladophora glomerata, extract oil from it, and characterize the extracted oil to gain insight into its physicochemical properties. The effects of parameters affecting the solvent extraction process, temperature, time and biomass particle size were investigated at a fixed solvent ratio of 4:1 hexane to ether. An optimization of oil separation from algae biomass via the solvent extraction method was studied. The obtained results showed that at the extraction temperature of 60 oC, extraction time of 2.5 h, and the particle size of ≤0.6 mm, the maximum oil yield was 18.3% from the process. The functional group analysis revealed the presence of alkane, esters, carboxylic acid, and unsaturated groups on the extracted oil, while the result from the fatty acid profile analysis confirmed the dominance of oleic acid. The physicochemical properties of the extracted algal oil conformed to the ASTM standard
Review on Prevalence of Waterborne Diseases in Nigeria
The 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
Waste Frying Oil as a Feedstock for Biodiesel Production
This study was initiated to blend the biodiesel produced from waste frying oil (WFO) with petroleum diesel in three different proportions (B20, B50 and B80), and the dual fuels were tested on compression ignition engine to evaluate their emission characteristics. The biodiesel produced from WFO was achieved via heterogeneous catalyzed transesterification using anthill-eggshell-Ni-Co mixed oxide composite catalyst at reaction temperature of 70°C, reaction time of 2 h, catalyst loading of 3 wt% and methanol to oil molar ratio of 12:1. Various analyses carried out on the prepared WFO-based biodiesel confirmed that it is of good quality and also meet the ASTM standard. The blended fuel containing 20% by volume biodiesel content (B20) emitted 1050 and 14,000 ppm of CO and CO2, respectively, which were lower than those emitted by B0, B50 and B80. It can be concluded that blending the diesel with appropriate volume of biodiesel not only improves its quality but also lowers greenhouse gases emission
Equilibrium, Kinetic and Thermodynamic Studies of theAdsorption of Heavy Metals from Aqueous Solution by ThermallyTreated Quail Eggshell
Background and Objective: Nowadays, the contamination of water resources by heavy metals has resulted in serious health issues. Themetals in their elemental as well as chemically combined form are toxic, non-degradable and persistence in nature. Thus, there is needto develop a simple, efficient and economical method for removing dissolved heavy metals from water/wastewater. In the presentstudy, it was aimed to prepare a new adsorbent from agricultural waste in order to remove Cu2+ and Zn2+ from aqueous solution.Materials and Methods: Calcium oxide (CaO) based material was prepared from quail eggshell, characterized and used as adsorbent forthe removal of Cu2+ and Zn2+ from aqueous solution. Calcined quail eggshell at 900EC was studied and exhibited high adsorption capacity.The effects of variables affecting the adsorption process, contact time, adsorbent dosage, temperature and initial heavy metalsconcentration were investigated at fixed pH of 4.5. Results: At contact time of 30 min, adsorbent dosage of 1.5 g, temperature of 35ECand initial Cu2+ and Zn2+ concentration of 150 mg LG1, the maximum heavy metals uptake could be achieved. Based on the value ofcorrelation coefficient, the experimental results for Cu2+ best fitted the Langmuir isotherm model with monolayer adsorption capacityof 13.49 mg gG1, while Freundlich isotherm model was best fitted to the experimental results for the Zn2+ adsorption. The kinetics andthermodynamic behaviours of the adsorption process were also investigated. Conclusion: The obtained results showed that theexperimental data were in good agreement with pseudo-second-order kinetic model. The results from thermodynamic analysis revealedthat the process is spontaneous and endothermi
A COMPARISON OF THE EFFECTS OF PREPARATION VARIABLES ON ACTIVITY OF COMPOSITE ANTHILL-CHICKEN EGGSHELL CATALYST FOR BIODIESEL PRODUCTION
This study is initiated to develop a composite catalyst from naturally occurring and waste
materials. The catalyst preparation conditions which include activation temperature (600-1000
o
C),
activation time (2-4 h) and mixing proportion of anthill to eggshell (1:1.5-1:4) were investigated using
central composite design (CCD) of response surface methodology (RSM) in design expert software.
A model that correlates the three process parameters to the response (biodiesel yield) was established.
The model reliability was evaluated using analysis of variance (ANOVA). The catalyst prepared
under the optimum conditions was characterized using scanning electron microscopy (SEM), Fourier
transform infrared radiation (FTIR) spectroscopy and X-ray Diffraction (XRD) technique. From the
ANOVA, both the predicted and experimental biodiesel yields agreed well with each other with
correlation coefficient (R
2)
of 0.9806. The optimum composite anthill-eggshell catalyst preparation
conditions were obtained as follow, activation temperature of 1000
o
C, 4 h activation time and anthill/
eggshell mixing ratio of 1:4, which provided biodiesel yield of 70.92
Review on Prevalence of Waterborne Diseases in Nigeria
The 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
Utilization of agricultural waste adsorbent for the removal of lead ions from aqueous solutions
This work investigated the potentiality of using chemically modified onion skin waste (CMOSW) as an adsorbent for the removal of lead ions (Pb2+) from an aqueous solution. The material properties were characterized using techniques, such as Brunauer-Emmett-Teller surface area analysis, scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. The effects of adsorbent dosage, contact time, pH and initial Pb2+ concentration on the removal efficiency were investigated by experimental tests. The experimental data were analysed by the Langmuir and Freundlich isotherms, while kinetic data obtained at different concentrations were analysed using a pseudo-first-order and pseudo-second-order models. A distinct adsorption of Pb2+ was revealed by the SEM results. From the FTIR analysis, the experimental result was corresponded to the peak changes of the spectra obtained before and after the adsorption of Pb2+. The maximum removal efficiency of Pb2+ by the CMOSW was 97.3±0.01% at an optimum CMOSW dosage of 1.4 g/L, contact time of 120 min and solution pH of 6.0. Experimental data obtained fitted well with the Freundlich isotherm model. The kinetics of the Pb2+ adsorption by CMOSW appeared to be better described by the pseudo-second-order model, suggesting the chemisorption mechanism dominance
Optimization and characterization of crude oil contaminated soil bioremediation using bacteria isolates:Plant growth effect
This 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