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Barka N.,Hassan 1er University | Abdennouri M.,Hassan 1er University | El Makhfouk M.,Equipe de Recherche Analyse controle et environnement ERACE | Qourzal S.,University Ibn Zohr
Journal of Environmental Chemical Engineering | Year: 2013

The biosorption of cadmium (II) and lead (II) ions onto a natural, plentiful and low-cost biosorbent developed from cactus cladodes was investigated in batch mode. Experiments were carried out as a function of average biosorbent particle size, pH, biosorbent mass, contact time, initial metal concentration and temperature. The experimental results indicate that, the percentage of biosorption increases with an increase in the biosorbent dosage and the decrease of particle size. The equilibrium uptake was increased with an increase in the initial metal concentration in solution. The maximum biosorption occurred at pH of 5.8 and 3.5, respectively for cadmium (II) and lead (II) ions. Biosorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The equilibrium data fitted very well to the Langmuir model with a maximum monolayer biosorption capacity of 30.42 and 98.62 mg/g, respectively for cadmium (II) and lead (II) ions. The biosorption yield decreases with an increase in solution temperature. The FTIR analysis of unloaded and metal loaded biosorbent indicated the involvement of CO, OC and COC groups in metal binding. © 2013 Elsevier Ltd. All rights reserved. Source


Barka N.,Hassan 1er University | Abdennouri M.,Hassan 1er University | Makhfouk M.E.,Equipe de Recherche Analyse controle et environnement ERACE
Journal of the Taiwan Institute of Chemical Engineers | Year: 2013

The biosorption of Methylene Blue (MB), Eriochrome Black T (EBT) and Alizarin S (AS) from aqueous solutions by dried prickly pear cactus cladodes as a low-cost, natural and eco-friendly biosorbent was investigated. The study was carried out under various parameters, such as average biosorbent particle size, pH, biosorbent dosage, contact time, initial dye concentration and temperature. The experimental results show that, the percentage of biosorption increases with an increase in the biosorbent dosage, and the decrease of particle size. The biosorption was pH dependent with a high biosorption of cationic dye (MB) in basic range and a high biosorption of anionic dyes (EBT and AS) in acidic range. The equilibrium uptake was increased with an increase in the initial dye concentration in solution. Biosorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The experimental isotherm data were analyzed using Langmuir, Freundlich, Redlich-Peterson, Temkin and Toth isotherm equations. The best fit was obtained by the Redlich-Peterson model and the Langmuir model with a Langmuir maximum monolayer biosorption capacity of 189.83. mg/g for Methylene Blue, 200.22. mg/g for Eriochrome Black T and 118.35. mg/g for Alizarin S. The biosorption was exothermic in nature (ΔH° = -31.035 kJ/mol for MB, -10.25 kJ/mol for EBT and -11.69 kJ/mol for AS). The reaction was accompanied by a decrease in entropy (ΔS° = -94.76 J/K mol for MB, -38.44 J/K mol for EBT and -41.93 J/K mol for AS). The Gibbs energy (ΔG°) increased when the temperature was increased from 25 to 60. °C indicating a decrease in feasibility of biosorption at higher temperatures. © 2012 Taiwan Institute of Chemical Engineers. Source


Abdennouri M.,University Hassan 1 | Elhalil A.,University Hassan 1 | Farnane M.,University Hassan 1 | Tounsadi H.,University Hassan 1 | And 10 more authors.
Journal of Saudi Chemical Society | Year: 2015

Titanium dioxide was synthesized by the sol-gel method and platinum supported on titanium dioxide were prepared by a wet impregnation chemical process at different platinum contents. The prepared samples were dried over night at 110°C and then calcined at 500°C for 4h. Structural and morphological characterization has been carried out by means of X-ray diffraction (XRD), differential scanning calorimetry-thermogravimetric analysis (DSC-TGA), Raman spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller surface area measurement (BET) and transmission electron microscopy coupled to the energy dispersive spectroscopy (TEM/EDX). The adsorption performance and photocatalytic activity of the samples were investigated using two chlorophenoxy herbicides: 2,4-dichlorophenoxyacetic acid (2,4-D) and 2-(2,4-dichlorophenoxy) propionic acid (2,4-DP) as models of organic pollutants in water. The obtained results show that Pt/TiO2 exhibited higher photocatalytic activity than TiO2 particles for the degradation of the two selected herbicides. The photocatalytic activity increases by increasing the platinum yield in the catalyst. © 2015 The Authors. Source


Barka N.,Hassan 1er University | Abdennouri M.,Equipe de Recherche Analyse controle et environnement ERACE | El Makhfouk M.,Equipe de Recherche Analyse controle et environnement ERACE | Qourzal S.,University Ibn Zohr | And 3 more authors.
Desalination and Water Treatment | Year: 2012

Calcium hydroxyapatite (Ca10(PO4)6(OH)2, Hap) was synthesized by a simple and rapid coprecipitation method. The samples were characterized by X-ray diffraction analysis, FT-IR spectral analysis, and transmission electron microscopy coupled energy-dispersive X-ray analysis (transmission electron microscope-energy dispersive X-ray spectrometer). The synthesized Hap was used as an adsorbent for the cadmium ion removal from aqueous solutions in batch mode. The influence of contact time and initial concentration of metal ion was studied and discussed. The equilibrium uptake increases with an increase in the initial cadmium concentration in solution. Adsorption kinetic data were properly fitted with the pseudo-second-order kinetic model. The experimental isotherm data were analyzed using Langmuir, Freundlich, Toth, and Tempkin isotherm equations. The best fit was obtained by the Toth model with high correlation coefficients (r2 > 0.99). The Langmuir model also yielded a good fit to experimental data (r2 around 0.98-0.99) with a maximum monolayer adsorption capacity of 240.74 mg/g. © 2012 Desalination Publications. All rights reserved. Source


Barka N.,University Hassan 1 | Abdennouri M.,Equipe de Recherche Analyse controle et environnement ERACE | Abdennouri M.,Chouaib Doukkali University | Boussaoud A.,Laboratoire Matiere | And 6 more authors.
Arabian Journal of Chemistry | Year: 2014

Full factorial experimental design technique was used to study the main effects and the interaction effects between operational parameters in the photocatalytic degradation of oxalic acid in a batch photo-reactor using TiO2 aqueous suspension. The important parameters which affect the removal efficiency of oxalic acid such as agitation, initial concentration, volume of the solution and TiO2 dosage were investigated. The parameters were coded as X1, X2, X3 and X4, consecutively, and were investigated at two levels (-1 and +1). The effects of individual variables and their interaction effects for dependent variables, namely, photocatalytic degradation efficiency (%) were determined. From the statistical analysis, the most effective parameters in the photocatalytic degradation efficiency were initial concentration and volume of solution. The interaction between initial concentration, volume of solution and TiO2 dosage was the most influencing interaction. However, the interaction between agitation, initial concentration and volume of solution was the least influencing parameter. © 2011. Source

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