• فهرست مقالات Direct red 81

      • دسترسی آزاد مقاله

        1 - Kinetic and Thermodynamic Studies on Biosorption of Direct Red 81 from Aqueous Solutions by Chamomilla Plant
        M. Momen Heravi A. Kodabande M. R. Bozorgmehr T. Ardalan P. Ardalan
        In this study, Chamomilla plant biomass used as a sorbent for biosorption of a textile dye, direct red 81, from an aqueous solution. The batch sorption was studied with respect to dye concentration, adsorbent dose and temperature. Also, kinetic and isotherm parameters w چکیده کامل
        In this study, Chamomilla plant biomass used as a sorbent for biosorption of a textile dye, direct red 81, from an aqueous solution. The batch sorption was studied with respect to dye concentration, adsorbent dose and temperature. Also, kinetic and isotherm parameters were determined for biosorption of Direct red 81 by Chamomilla plant. The maximum biosorption capacity (qm) of Direct red 81 10 mg g-1 was obtained at 25oC. The kinetic and isotherm studies indicated that the biosorption process obeys a pseudo-second order and Langmuir isotherm models. In addition, various thermodynamic parameters, such as changes in Gibbs free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) have been calculated. The biosorption process of Direct Red 81 dye onto activated carbon prepared from Chamomilla plant was found to be spontaneous and exothermic. The findings of this investigation suggest that this procces is a physical biosorption. The experimental studies indicated that Chamomilla plant had the potential to act as an alternative biosorbent to remove the Direct Red 81 dye from an aqueous solution. پرونده مقاله
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        2 - Equilibrium and Kinetic Studies of Direct Red 81 Biosorption onto Modified Silk Maze as an Economical Biosorbent
        Mohammad Momen Heravi Pouran Ardalan Alireza Vafaie
        In this study, the potential of biosorbent obtained from silk maze, was investigated for the batch biosorption of Direct red 81 (DR 81) in aqueous solution. The effects of temperature, biosorbent amount, contact time, initial dye concentration and ultrasonic irradiation چکیده کامل
        In this study, the potential of biosorbent obtained from silk maze, was investigated for the batch biosorption of Direct red 81 (DR 81) in aqueous solution. The effects of temperature, biosorbent amount, contact time, initial dye concentration and ultrasonic irradiation were also evaluated. Furthermore, experimental equilibrium and kinetics data were fitted by Langmuir and Freundlich isotherms and pseudo-first-order and pseudo-second-order kinetic models, respectively. Kinetic experiments revealed that the biosorption of DR 81 onto modified silk maze can be described with a pseudo second-order model while the equilibrium isotherm data were well described by the Freundlich model. The negative thermodynamic values of ΔHoand ΔGoshowed that the biosorption is an endothermic process and occurs spontaneously in the nature.The results presented that this waste material may be a suitable biosorbent for removal of industrial effluents due to its low cost and high efficiency. پرونده مقاله