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Mohammad I Elkhaiary - One of the best experts on this subject based on the ideXlab platform.
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malachite green Adsorption by rattan sawdust isotherm kinetic and mechanism modeling
Journal of Hazardous Materials, 2008Co-Authors: B H Hameed, Mohammad I ElkhaiaryAbstract:Abstract In this work, the Adsorption of malachite green (MG) on rattan sawdust (RSD) was studied at 30 °C. The results indicated that RSD can be used as a low-cost adsorbent for the removal of MG dye from aqueous solutions. Equilibrium data were analyzed by two isotherms, namely the Freundlich isotherm and the Langmuir isotherm. The best fit to the data was obtained with the Langmuir isotherm. The monolayer Adsorption capacity of RSD was found to be 62.71 mg/g. The Adsorption kinetics can be predicted by the pseudo-first-order model. The mechanism of Adsorption was also studied. It was found that for a short time period the Rate of Adsorption is controlled by film diffusion. However, at longer Adsorption times, pore-diffusion controls the Rate of Adsorption. The amount adsorbed on the outer surface was estimated from the time where film-diffusion stops controlling the Adsorption Rate.
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removal of basic dye from aqueous medium using a novel agricultural waste material pumpkin seed hull
Journal of Hazardous Materials, 2008Co-Authors: B H Hameed, Mohammad I ElkhaiaryAbstract:In this work, pumpkin seed hull (PSH), an agricultural solid waste, is proposed as a novel material for the removal of methylene blue (MB) from aqueous solutions. The effects of the initial concentration, agitation time and solution pH were studied in batch experiments at 30 °C. The equilibrium process was described well by the multilayer Adsorption isotherm. The Adsorption kinetics can be predicted by the pseudo-first-order and the modified pseudo-first-order models. The mechanism of Adsorption was also studied. It was found that for a short time period the Rate of Adsorption is controlled by film diffusion. However, at longer Adsorption times, pore-diffusion controls the Rate of Adsorption. Pore diffusion takes place in two distinct regimes, corresponding to diffusion in macro- and mesopores. The results demonstRate that the PSH is very effective in the removal of MB from aqueous solutions.
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kinetics and equilibrium studies of malachite green Adsorption on rice straw derived char
Journal of Hazardous Materials, 2008Co-Authors: B H Hameed, Mohammad I ElkhaiaryAbstract:In this work, the potential feasibility of rice straw-derived char (RSC) for removal of C.I. Basic Green 4 (malachite green (MG)), a cationic dye from aqueous solution was investigated. The isotherm parameters were estimated by non-linear regression analysis. The equilibrium process was described well by the Langmuir isotherm model. The maximum RSC sorption capacity was found to be 148.74 mg/L at 30 °C. The kinetics of MG sorption on RSC followed the Lagergren's pseudo-first-order model and the overall Rate of dye uptake was found to be controlled by external mass transfer at the beginning of Adsorption, while intraparticle diffusion controlled the overall Rate of Adsorption at a later stage. The results indicated that RSC was an attractive adsorbent for removing basic dye from aqueous solutions.
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kinetics and mechanism of Adsorption of methylene blue from aqueous solution by nitric acid treated water hyacinth
Journal of Hazardous Materials, 2007Co-Authors: Mohammad I ElkhaiaryAbstract:Kinetics Adsorption experiments were conducted to evaluate the Adsorption characteristics of a cationic dye (methylene blue, MB) onto nitric-acid treated water-hyacinth (N-WH). Results showed that N-WH can remove MB effectively from aqueous solution. The loading of MB onto N-WH was found to increase significantly with increasing the initial MB concentration, but the residual concentration of MB in solution also increased. A complete removal of MB from solution was only achieved at the lower range of initial MB concentration (less than 286 mg/L). Temperature had a slight effect on the amount adsorbed at equilibrium. The Adsorption Rate was fast and more than half of the adsorbed-MB was removed in the first 15 min at room temperature, which makes the process practical for industrial application. The Adsorption kinetics at room temperature could be expressed by the pseudo second order model, while at higher temperatures (45-80 degrees C) and low MB concentration (97 mg/L) both Lagergren's model and the pseudo second order model can be used to predict the kinetics of Adsorption. The overall Rate of dye uptake was found to be controlled by external mass transfer at the beginning of Adsorption, then gradually changed to intraparticle diffusion control at a later stage. The initial period where external mass transfer is the Rate controlling step was found to increase with increasing initial MB concentration and decrease with increasing temperature. The increase in temperature was also found to increase the Rate of Adsorption and reduce the time required to reach equilibrium. The initial Rate of Adsorption, h(o), was calculated, it was found to increase with increasing temperature, while the increase in MB concentration decreased h(o) at the lower concentration range then increased h(o) again at high concentration. The value of the activation coefficient, E, was found to be 8.207 kJ/mol, which indicates a diffusion controlled process.
C Aldrich - One of the best experts on this subject based on the ideXlab platform.
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Adsorption of heavy metals by biomaterials derived from the marine alga Ecklonia maxima
Hydrometallurgy, 2004Co-Authors: D Feng, C AldrichAbstract:Abstract The Adsorption of heavy metals onto biomaterial derived from the marine alga Ecklonia maxima was investigated via batch experiments. The Adsorption equilibria of Cu, Pb and Cd could be represented by Langmuir isotherms and the capacity of fresh alga for Cu, Pb and Cd was approximately 85–94, 227–243 and 83.5 mg/g dry alga, respectively. The Rate of Adsorption onto the marine alga was high. The alga particle size played an important role in the Adsorption behaviour. The coarse alga particles had a higher Adsorption capacity and slower Adsorption kinetics and could be regeneRated without significant loss of capacity. In contrast, the fine alga particles had a lower Adsorption capacity and faster Adsorption kinetics and could not be regeneRated without significant loss of capacity. Comparison with a commercial resin indicated that the activated biomass derived from E. maxima could be used as an efficient biosorbent for the treatment of waste waters containing heavy metals.
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Adsorption of heavy metals by biomaterials derived from the marine alga Ecklonia maxima
Hydrometallurgy, 2004Co-Authors: D Feng, C AldrichAbstract:The Adsorption of heavy metals onto biomaterial derived from the marine alga Ecklonia maxima was investigated via batch experiments. The Adsorption equilibria of Cu, Pb and Cd could be represented by Langmuir isotherms and the capacity of fresh alga for Cu, Pb and Cd was approximately 85-94, 227-243 and 83.5 mg/g dry alga, respectively. The Rate of Adsorption onto the marine alga was high. The alga particle size played an important role in the Adsorption behaviour. The coarse alga particles had a higher Adsorption capacity and slower Adsorption kinetics and could be regeneRated without significant loss of capacity. In contrast, the fine alga particles had a lower Adsorption capacity and faster Adsorption kinetics and could not be regeneRated without significant loss of capacity. Comparison with a commercial resin indicated that the activated biomass derived from E. maxima could be used as an efficient biosorbent for the treatment of waste waters containing heavy metals. © 2004 Elsevier B.V. All rights reserved.Articl
Xin Wang - One of the best experts on this subject based on the ideXlab platform.
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biosorption of cadmium ii zinc ii and lead ii by penicillium simplicissimum isotherms kinetics and thermodynamics
Journal of Hazardous Materials, 2008Co-Authors: Baoying Feng, Guangming Zeng, Chunping Yang, Ming Zhou, Haizhou Zhou, Xin WangAbstract:Abstract The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich–Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini–Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the Rate of Adsorption followed the pseudo second-order kinetics well. The thermodynamics constants Δ G °, Δ H ° and Δ S ° of the Adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum were endothermic and spontaneous.
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biosorption of cadmium ii zinc ii and lead ii by penicillium simplicissimum isotherms kinetics and thermodynamics
Journal of Hazardous Materials, 2008Co-Authors: Ting Fan, Baoying Feng, Guangming Zeng, Chunping Yang, Ming Zhou, Haizhou Zhou, Yunguo Liu, Zhenfeng Tan, Xin WangAbstract:The isotherms, kinetics and thermodynamics of Cd(II), Zn(II) and Pb(II) biosorption by Penicillium simplicissimum were investigated in a batch system. The effects of pH, initial metal ions concentration, biomass dose, contact time, temperature and co-ions on the biosorption were studied. Adsorption data were well described by both the Redlich-Peterson and Langmuir model. Chemical ion-exchange was found to be an important process based on free energy value from Dubini-Radushkevich isotherm for all metal ions. The results of the kinetic studies of all metal ions at different temperature showed that the Rate of Adsorption followed the pseudo second-order kinetics well. The thermodynamics constants DeltaG degrees , DeltaH degrees and DeltaS degrees of the Adsorption process showed that biosorption of Cd(II), Zn(II) and Pb(II) ions on Penicillium simplicissimum were endothermic and spontaneous.
Krzysztof Kaczmarski - One of the best experts on this subject based on the ideXlab platform.
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on the optimization of the solid core radius of superficially porous particles for finite Adsorption Rate
Journal of Chromatography A, 2011Co-Authors: Krzysztof KaczmarskiAbstract:Abstract Packed chromatographic columns with the superficially porous particles (porous shell particles) guarantee higher efficiency. The theoretical equation of the Height Equivalent to a Theoretical Plate (HETP), for columns packed with spherical superficially porous particles, was used for the analysis of the column efficiency for finite Rate of Adsorption–desorption process. The HETP equation was calculated by the application of the moment analysis to elution peaks evaluated with the General Rate (GR) model. The optimal solid core radius for maximum column efficiency was estimated for a wide spectrum of internal and external mass transfer resistances, Adsorption kinetic Rate and axial dispersion. The separation power of the shell adsorbent for two component mixture, in analytical and preparative chromatography, was discussed. The conditions of the equivalence between the solutions of the General Rate model with slow Adsorption kinetic and the Lumped Kinetic Model (LKM) or the Equilibrium Dispersive (ED) model were formulated.
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on the optimization of the solid core radius of superficially porous particles for finite Adsorption Rate
Journal of Chromatography A, 2011Co-Authors: Krzysztof KaczmarskiAbstract:Abstract Packed chromatographic columns with the superficially porous particles (porous shell particles) guarantee higher efficiency. The theoretical equation of the Height Equivalent to a Theoretical Plate (HETP), for columns packed with spherical superficially porous particles, was used for the analysis of the column efficiency for finite Rate of Adsorption–desorption process. The HETP equation was calculated by the application of the moment analysis to elution peaks evaluated with the General Rate (GR) model. The optimal solid core radius for maximum column efficiency was estimated for a wide spectrum of internal and external mass transfer resistances, Adsorption kinetic Rate and axial dispersion. The separation power of the shell adsorbent for two component mixture, in analytical and preparative chromatography, was discussed. The conditions of the equivalence between the solutions of the General Rate model with slow Adsorption kinetic and the Lumped Kinetic Model (LKM) or the Equilibrium Dispersive (ED) model were formulated.
D Feng - One of the best experts on this subject based on the ideXlab platform.
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Adsorption of heavy metals by biomaterials derived from the marine alga Ecklonia maxima
Hydrometallurgy, 2004Co-Authors: D Feng, C AldrichAbstract:Abstract The Adsorption of heavy metals onto biomaterial derived from the marine alga Ecklonia maxima was investigated via batch experiments. The Adsorption equilibria of Cu, Pb and Cd could be represented by Langmuir isotherms and the capacity of fresh alga for Cu, Pb and Cd was approximately 85–94, 227–243 and 83.5 mg/g dry alga, respectively. The Rate of Adsorption onto the marine alga was high. The alga particle size played an important role in the Adsorption behaviour. The coarse alga particles had a higher Adsorption capacity and slower Adsorption kinetics and could be regeneRated without significant loss of capacity. In contrast, the fine alga particles had a lower Adsorption capacity and faster Adsorption kinetics and could not be regeneRated without significant loss of capacity. Comparison with a commercial resin indicated that the activated biomass derived from E. maxima could be used as an efficient biosorbent for the treatment of waste waters containing heavy metals.
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Adsorption of heavy metals by biomaterials derived from the marine alga Ecklonia maxima
Hydrometallurgy, 2004Co-Authors: D Feng, C AldrichAbstract:The Adsorption of heavy metals onto biomaterial derived from the marine alga Ecklonia maxima was investigated via batch experiments. The Adsorption equilibria of Cu, Pb and Cd could be represented by Langmuir isotherms and the capacity of fresh alga for Cu, Pb and Cd was approximately 85-94, 227-243 and 83.5 mg/g dry alga, respectively. The Rate of Adsorption onto the marine alga was high. The alga particle size played an important role in the Adsorption behaviour. The coarse alga particles had a higher Adsorption capacity and slower Adsorption kinetics and could be regeneRated without significant loss of capacity. In contrast, the fine alga particles had a lower Adsorption capacity and faster Adsorption kinetics and could not be regeneRated without significant loss of capacity. Comparison with a commercial resin indicated that the activated biomass derived from E. maxima could be used as an efficient biosorbent for the treatment of waste waters containing heavy metals. © 2004 Elsevier B.V. All rights reserved.Articl
