Sadegh Roushenas; Maryam Female Nikzad; Ali Asghar Ghoreyshi; mohsen ghorbani
Abstract
In this study, pectin/γ-Fe2O3/gl nanocomposite was synthesized using a single-step chemical precipitation method and used as an eco-friendly adsorbent to remove Cd2+ and Pb2+ from aqueous solution. The nanocomposite was characterized by FE-SEM, EDX, FTIR, XRD, VSM, and TEM analyses. The effect ...
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In this study, pectin/γ-Fe2O3/gl nanocomposite was synthesized using a single-step chemical precipitation method and used as an eco-friendly adsorbent to remove Cd2+ and Pb2+ from aqueous solution. The nanocomposite was characterized by FE-SEM, EDX, FTIR, XRD, VSM, and TEM analyses. The effect of various parameters such as solution pH (2 to 5), contact time (0 to 60 min), initial ion concentration (10 to 200 mg. L-1), and adsorbent dosage (0.1 to 0.4 g.L-1) on the removal efficiency was investigated. The maximum adsorption capacity of Cd (II) in the conditions (pH: 5, dose of adsorbent: 0.2 g.L-1, and contact time:40 min, initial concentration: 50 mg.L-1 ) and Pb (II) in the conditions (pH: 4.5, dose of adsorbent: 0.1g.L-1, and contact time:30min, initial concentration: 50 mg.L-1 ) was 470 and 325 mg. g-1, respectively. The adsorption kinetics was studied using several kinetic models including Langmuir isotherm, Freundlich isotherm, Sips isotherm, and Temkin isotherm. Results indicated that the adsorption mechanism could be well represented by the pseudo-second-order model. The equilibrium data of Cd (II) and Pb (II) adsorption were reasonably described by the Sips and Langmuir isothermal models. The positive value of delta H and negative values of delta G exhibit the endothermic and spontaneous nature of the adsorption process.
Lida Rahmanzadeh; Mohsen Ghorbani; Mohsen Jahanshahi
Abstract
Mercury is one of the most toxic metals present in the environment. Adsorption has been proposed among the technologies for mercury adsorbent. The kinetics of adsorption depends on the adsorbent concentration, and the physical and chemical characteristics of adsorbent. In this study we were used a novel ...
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Mercury is one of the most toxic metals present in the environment. Adsorption has been proposed among the technologies for mercury adsorbent. The kinetics of adsorption depends on the adsorbent concentration, and the physical and chemical characteristics of adsorbent. In this study we were used a novel adsorbent, magnetite-polyrhodanine core- shell nanoparticles, for removing Hg(II) from aqueous solution. The effect of pH, initial Hg(II) concentration, initial adsorbent concentration and contact time on the efficiency of Hg(II) removal were investigated systematically by batch experiments. The maximum adsorption capacity was obtained 29.14 mg g-1 at PH=6.5 and 25°C with 10 g L-1 nano adsorbent. The kinetic data of adsorption of Hg(II) ion on the synthesized adsorbent were best described by a pseudo- second- order equation, indicating their chemical adsorption. The Freundlich, Langmuir and Temkin isotherms were used to modeling of mercury adsorption on Hg(II) in aqueous medium which modeled best by the Freundlich isotherm is whole concentration rage.