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The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Z Derriche – 1st expert on this subject based on the ideXlab platform
Color Removal from Acid and Reactive Dye Solutions by Electrocoagulation and Electrocoagulation/Adsorption ProcessesWater Environment Research, 2009Co-Authors: S. Bellebia, S. Kacha, Zohra Bouberka, A.z. Bouyakoub, 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]
sorption study of an Acid Dye from an aqueous solutions using modified claysJournal 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 – 2nd expert on this subject based on the ideXlab platform
intraparticle diffusion processes during Acid Dye adsorption onto chitosanBioresource 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.
intraparticle diffusion in single and multicomponent Acid Dye adsorption from wastewater onto carbonChemical 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.
preparation of activated carbon using low temperature carbonisation and physical activation of high ash raw bagasse for Acid Dye adsorptionChemosphere, 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.
Monica Periolatto – 3rd expert on this subject based on the ideXlab platform
ultrasound for low temperature Dyeing of wool with Acid DyeUltrasonics 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.