Browsing by Author "Atulegwu, Patrick Uzoije"

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    Adsorption kinetics and Mechanisms of cypermethrin and dichlorovos on heterogeneous activated carbon porous media
    (Federal University of Technology, Owerri, 2015-11-18) Atulegwu, Patrick Uzoije; Kamalu, Clinfford O.; Uzuakpundu, Basil
    Adsorption kinetics and mechanism of Cypermethrin (CY) and Dichlorovos (DI) on activated car bons of oil bean seed shell (OBSS), unripe plantain peel (UPP) and castor bean seed shell (CBSS) systems have been studied. The equilibrium adsorption isotherms were modelled by Freunlich, Langmuir and Langmuir-Freunlich (LF) models. Adsorption isotherms of various systems were best described by Langmuir-Freunlich (LF). Mixed 1,2 order equation (MOE), integrated kinetic Langmuir (IKL), pseudo second order equation (PSOE), fractal-like mixed 1,2 order equation (F-MOE), and Boyd and Webbers models were compared and adopted in the analysis of the kinetic data. The models represented different uptake reduction rate of CY and DI by various adsorption systems. F-MOE, IKL and MOE models were in agreement with CY/OBSS, CY/UPP and CY/CBSS sys tem data respectively, hence the conforming models, whereas IKL, MOE and PSOE were the con forming models for DI/OBSS, DI/UPP and DI/CBSS adsorption data systems, respectively. The two diffusion models (Boyd and Webbers) applied confirmed film diffusion pattern as prevailing transportation pathway for CY and DI onto the adsorbents.
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    Modeling lateral distribution of heavy metal and bio-accumulation in earthworm in the varying acidic surface horizon of waste-polluted soil
    (U. P., 2013) Atulegwu, Patrick Uzoije; Uzoigwe, Luke; Otuonye, Erick; Kamalu, Clifford O.; Onunkwo-Akunne, Austine
    Heavy metal concentrations and its distributions in the soil have been a source of concern to soil usage, particularly to agriculture as concentration and distribution of heavy metal determine to a large extent, the soil quality and consequently that of the crops. The ability to quantify the amount of heavy metal in the soil is of immense importance to soil management. The use of accurate model is essential to estimate the actual soil heavy metal values and its distribution for efficient management. In this study, soil and earthworm samples of the battery-waste-polluted site and that of the background site were collected from five different locations(A,B,C,D and E) along the gradient of decreasing pollution. With five replicates each form one sampling location, twenty–five soil and fifty earthworms samples (two earthworms from each replicate) were collected using stratified random sampling technique. Lead(pb), Cadmium(Cd), Chromium(Cr), Nickel(Ni), Manganese(Mn), Arsenic(As), pH and Mercury(Hg) were analyzed using standard methods. The same process was replicated for the background site. Values of the heavy metals in soil and earthworms were natural and typical of Ameki-Nanka-soil formation. The average range of heavy metals concentrations in soil and earthworm samples from the polluted site were; pb(1025-695 mg/kg), Cd(11.34-6.3 mg/kg), Mn(290-81 mg/kg), pH(2.3-6.9mg/kg),Cr(185-3.7 mg/kg), Ni(12.87-1.7 mg/kg), As(72-4.5 mg/kg), Hg(1.7-0.002mg/kg) and pb(193-37.98 mg/kg), Cd(14.04-0.01 mg/kg), Mn(17.34-1.10mg/kg), pH(6.9-2.3mg/kg), Cr(8.45-0.01 mg/kg), Ni(1.41-0.03 mg/kg), As(0.75-0.01 mg/kg), Hg(0.4-0.009mg/kg) respectively. Concentrations of heavy metals for soil and earthworm samples decreased along the gradient of decreasing pollution of the polluted site. Three models(Linear , Logarithmic and quadratic models) were developed to test their suitability to the data in which Ph was correlated with heavy metals. Inverse correlation was observed with coefficient R2 of between 0.77-0.95 and lowest percentage deviation of the field from the predicted values.
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    The impact of urban run-off on Ogbor River
    (U. P., 2005) Atulegwu, Patrick Uzoije
    Impact of urban run-off on Ogbor River in Aba metropolis has been studied. The run-off contains toxic chemical, heavy metals and suspended solids. Water samples were collected from three discharged points in the months of May to September. The results of the analysis of the samples show high-level concentration of lead, iron, cadmium, cyanide and chromium (1.7mg/l, 5.52mg/l, 1.47mg/l, 2.44mg/l and 1.31mg/I respectively). However, the water sample of the slaughter house,and the industrial effluents are free from heavy metals. In addition, the water quality of the downstream location of the river shows an appreciable reduction of the concentration of the heavy metals probably due to dispersion effect. The presence of this pollution in water is hazardous to health. Ballasted flocculation technology can be used to reduce .