The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Z Derriche - One of the best experts on this subject based on the ideXlab platform.
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Color Removal from Acid and Reactive Dye Solutions by Electrocoagulation and Electrocoagulation/Adsorption Processes
Water Environment Research, 2009Co-Authors: S. Bellebia, A.z. Bouyakoub, S. Kacha, Zohra Bouberka, Z DerricheAbstract:In this study, electrocoagulation of Marine Blue Erionyl MR (Acid Dye) and electrocoagulation followed by adsorption of Brilliant Blue Levafix E-BRA (reactive Dye) from aqueous solutions were investigated, using aluminum electrodes and granular activated carbon (GAC). In the electrocoagulation and adsorption of Dyestuff solutions, the effects of current density, loading charge, pH, conductivity, stirring velocity, contact time, and GAC concentration were examined. The optimum conditions for the electrocoagulation process were identified as loading charges 7.46 and 1.49 F/m^sup 3^, for a maximum abatement of 200 mg/L reactive and Acid Dye, respectively. The residual reactive Dye concentration was completely removed with 700 mg/L GAC. The results of this investigation provide important data for the development of a combined process to remove significant concentrations of recalcitrant Dyes from water, using moderate activated carbon energy and aluminum consumption, and thereby lowering the cost of treatment. [PUBLICATION ABSTRACT]
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sorption study of an Acid Dye from an aqueous solutions using modified clays
Journal of Hazardous Materials, 2005Co-Authors: Zohra Bouberka, Smail Kacha, M Kameche, S Elmaleh, Z DerricheAbstract:Abstract The removal of the pollutant Supranol Yellow 4GL (S.Y.4GL) was studied by using different clays: clay exchanged with sodium (BNa+) and hydroxyaluminic polycation pillared clays in the presence or absence of non-ionic surfactant. While decomposing the surfactant at 500 °C, the surface of the clay changed significantly. The study of the behaviour of the three clays with respect to coloring solutions, allowed to determine the equilibrium time and the rate-determining step of the Dye S.Y.4GL adsorption. Two simplified kinetic models, were tested to investigate the adsorption mechanisms in terms of pseudo-first order and pseudo-second order equations. Besides, the adsorption capacity data were fitted to Langmuir and Freundlich equations as well. A better fixation was obtained with an Acidic pH. The effect of temperature on the adsorption of Dye has been also studied and the thermodynamic parameters ΔG°, ΔH° and ΔS° were determined.
Gordon Mckay - One of the best experts on this subject based on the ideXlab platform.
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intraparticle diffusion processes during Acid Dye adsorption onto chitosan
Bioresource Technology, 2007Co-Authors: W H Cheung, Yau Shan Szeto, Gordon MckayAbstract:The adsorption of five Acid Dyes onto chitosan was studied. The equilibrium capacities based on the Langmuir analysis were 1.54, 2.66, 1.11, 1.25 and 1.03 mmol/g chitosan for Orange 10 (AO10), Acid Orange 12 (AO12), Acid Red 18 (AR18), Acid Red 73 (AR73) and Acid Green 25 (AG25) respectively. The batch adsorption rate for the five systems based on an intraparticle diffusion rate parameter derived from the plots of Dye adsorbed versus the square root of time indicated that the adsorption mechanism was predominantly intraparticle diffusion but there was also a dependence on pore size as the Dye diffuses through macropore, mesopore and micropore respectively.
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intraparticle diffusion in single and multicomponent Acid Dye adsorption from wastewater onto carbon
Chemical Engineering Journal, 2004Co-Authors: Keith K H Choy, John F Porter, Gordon MckayAbstract:Abstract The adsorption of three Acid Dyes onto activated carbon has been studied. Three single, three binary and one ternary systems have been investigated and both equilibrium and kinetic studies have been determined. The equilibrium capacities based on the Langmuir analysis are 0.253, 0.125 and 0.219 mmol g −1 carbon for Acid Blue 80, Acid Red 114 and Acid Yellow 117, respectively. The batch adsorber rate data for the seven systems have been analysed based on an intraparticle diffusion rate parameter derived from the plots of Dye adsorbed versus the square root of time. The data indicate the adsorption mechanism is predominantly intraparticle diffusion. The multicomponent system rate parameters have been correlated with the single component rate parameters by the use of the Langmuir equilibrium parameters.
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preparation of activated carbon using low temperature carbonisation and physical activation of high ash raw bagasse for Acid Dye adsorption
Chemosphere, 2004Co-Authors: M Valix, W H Cheung, Gordon MckayAbstract:Abstract Activated carbons were prepared from bagasse through a low temperature (160 °C) chemical carbonisation treatment and gasification with carbon dioxide at 900 °C. The merit of low temperature chemical carbonisation in preparing chars for activation was assessed by comparing the physical and chemical properties of activated carbons developed by this technique to conventional methods involving the use of thermal and vacuum pyrolysis of bagasse. In addition, the adsorption properties (Acid blue Dye) of these bagasse activated carbons were also compared with a commercial activated carbon. The results suggest that despite the high ash content of the precursor, high surface areas (614–1433 m 2 g −1 ) and microporous (median pore size from 0.45 to 1.2 nm) activated carbons can be generated through chemical carbonisation and gasification. The micropore area of the activated carbon developed from chars prepared by the low temperature chemical carbonisation provides favourable adsorption sites to Acid blue Dye (391 mg g −1 of carbon). The alkalinity of the carbon surface and total surface area were shown to have complementary effects in promoting the adsorption of Acid blue Dye. Adsorption of the anionic coloured component of the Acid Dye was shown to be promoted in carbon exhibiting alkaline or positively charged surfaces. This study demonstrates that activated carbons with high Acid Dye adsorption capacities can be prepared from high ash bagasse based on low temperature chemical carbonisation and gasification.
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equilibrium studies for Acid Dye adsorption onto chitosan
Langmuir, 2003Co-Authors: Y C Wong, Yau Shan Szeto, W H Cheung, Gordon MckayAbstract:The ability of chitosan as an adsorbent for the removal of Acid Dyestuff, namely, Acid green 25, Acid orange 10, Acid orange 12, Acid red 18, and Acid red 73, from aqueous solution has been studied. The experimental equilibrium data for the single component Dye−chitosan systems have been analyzed using the linearized forms of Langmuir, Freundlich, and Redlich−Peterson isotherms. The Langmuir isotherm was found to provide the best theoretical correlation of the experimental data for the adsorption of all five Acid Dyes. On the basis of the Langmuir analysis, the monolayer adsorption (saturation) capacities were determined to be 645.1, 922.9, 973.3, 693.2, and 728.2 mg of Dye per gram of chitosan for Acid green 25, Acid orange 10, Acid orange 12, Acid red 18, and Acid red 73, respectively. The differences in adsorption capacities may be due to the effect of molecular size and the number of sulfonate groups of each Dye. The results demonstrated that monovalent and/or smaller Dye molecules have superior adsor...
Monica Periolatto - One of the best experts on this subject based on the ideXlab platform.
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ultrasound for low temperature Dyeing of wool with Acid Dye
Ultrasonics Sonochemistry, 2012Co-Authors: Franco Ferrero, Monica PeriolattoAbstract:Abstract The possibility of reducing the temperature of conventional wool Dyeing with an Acid levelling Dye using ultrasound was studied in order to reach exhaustion values comparable to those obtained with the standard procedure at 98 °C, obtaining Dyed samples of good quality. The aim was to develop a laboratory method that could be transferred at industrial level, reducing both the energy consumption and fiber damage caused by the prolonged exposure to high temperature without the use of polluting auxiliary agents. Dyeings of wool fabrics were carried out in the temperature range between 60 °C and 80 °C using either mechanical or ultrasound agitation of the bath and coupling the two methods to compare the results. For each Dyeing, the exhaustion curves of the Dye bath were determined and the better results of Dyeing kinetics were obtained with ultrasound coupled with mechanical stirring. Hence the corresponding half Dyeing times, absorption rate constants according to Cegarra–Puente modified equation and ultrasonic efficiency were calculated in comparison with mechanical stirring alone. In the presence of ultrasound the absorption rate constants increased by at least 50%, at each temperature, confirming the synergic effect of sonication on the Dyeing kinetics. Moreover the apparent activation energies were also evaluated and the positive effect of ultrasound was ascribed to the pre-exponential factor of the Arrhenius equation. It was also shown that the effect of ultrasound at 60 °C was just on the Dye bath, practically unaffecting the wool fiber surface, as confirmed by the results of SEM analysis. Finally, fastness tests to rubbing and domestic laundering yielded good values for samples Dyed in ultrasound assisted process even at the lower temperature. These results suggest the possibility, thanks to the use of ultrasound, to obtain a well equalized Dyeing on wool working yet at 60 °C, a temperature process strongly lower than 98 °C, currently used in industry, which damages the mechanical properties of the fibers.
P K Malik - One of the best experts on this subject based on the ideXlab platform.
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use of activated carbons prepared from sawdust and rice husk for adsorption of Acid Dyes a case study of Acid yellow 36
Dyes and Pigments, 2003Co-Authors: P K MalikAbstract:Activated carbons, prepared from low-cost mahogany sawdust and rice husk have been utilized as the adsorbents for the removal of Acid Dyes from aqueous solution. An Acid Dye, Acid Yellow 36 has been used as the adsorbate. Results show that a pH value of 3 is favourable for the adsorption of Acid Dye. The isothermal data could be well described by the Langmuir and Freundlich equations. Kinetic parameters of adsorption such as the Langergren pseudo-first-order constant and the intraparticle diffusion rate constant were determined. For the present adsorption process, intraparticle diffusion of Dye molecule within the particle has been identified to be rate limiting. The adsorption capacities of sawdust carbon (SDC) and rice husk carbon (RHC) were found to be 183.8 mg and 86.9 mg per g of the adsorbent respectively. The results indicate that SDC and RHC could be employed as low-cost alternatives to commercial activated carbon in wastewater treatment for the removal of Acid Dyes.
Zohra Bouberka - One of the best experts on this subject based on the ideXlab platform.
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Color Removal from Acid and Reactive Dye Solutions by Electrocoagulation and Electrocoagulation/Adsorption Processes
Water Environment Research, 2009Co-Authors: S. Bellebia, A.z. Bouyakoub, S. Kacha, Zohra Bouberka, Z DerricheAbstract:In this study, electrocoagulation of Marine Blue Erionyl MR (Acid Dye) and electrocoagulation followed by adsorption of Brilliant Blue Levafix E-BRA (reactive Dye) from aqueous solutions were investigated, using aluminum electrodes and granular activated carbon (GAC). In the electrocoagulation and adsorption of Dyestuff solutions, the effects of current density, loading charge, pH, conductivity, stirring velocity, contact time, and GAC concentration were examined. The optimum conditions for the electrocoagulation process were identified as loading charges 7.46 and 1.49 F/m^sup 3^, for a maximum abatement of 200 mg/L reactive and Acid Dye, respectively. The residual reactive Dye concentration was completely removed with 700 mg/L GAC. The results of this investigation provide important data for the development of a combined process to remove significant concentrations of recalcitrant Dyes from water, using moderate activated carbon energy and aluminum consumption, and thereby lowering the cost of treatment. [PUBLICATION ABSTRACT]
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sorption study of an Acid Dye from an aqueous solutions using modified clays
Journal of Hazardous Materials, 2005Co-Authors: Zohra Bouberka, Smail Kacha, M Kameche, S Elmaleh, Z DerricheAbstract:Abstract The removal of the pollutant Supranol Yellow 4GL (S.Y.4GL) was studied by using different clays: clay exchanged with sodium (BNa+) and hydroxyaluminic polycation pillared clays in the presence or absence of non-ionic surfactant. While decomposing the surfactant at 500 °C, the surface of the clay changed significantly. The study of the behaviour of the three clays with respect to coloring solutions, allowed to determine the equilibrium time and the rate-determining step of the Dye S.Y.4GL adsorption. Two simplified kinetic models, were tested to investigate the adsorption mechanisms in terms of pseudo-first order and pseudo-second order equations. Besides, the adsorption capacity data were fitted to Langmuir and Freundlich equations as well. A better fixation was obtained with an Acidic pH. The effect of temperature on the adsorption of Dye has been also studied and the thermodynamic parameters ΔG°, ΔH° and ΔS° were determined.
