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Arshadi M.,Islamic Azad University at Fasa | Salimivahid F.,Mapua Institute of Technology | Salvacion J.W.L.,Mapua Institute of Technology | Soleymanzadeh M.,Mapua Institute of Technology
RSC Advances | Year: 2014

In this paper, a novel nano-adsorbent containing Mn-nanoparticle decorated organo-functionalized SiO2-Al2O3 mixed-oxide was introduced as a new scavenger of dyes such as methyl orange. The SiO 2-Al2O3 mixed-oxide was functionalized with a Schiff base ligand and thereafter, in the next step, Mn-nanoparticles were prepared over the organo-functionalized SiO2-Al2O 3 mixed-oxide. The synthesized materials were characterized by several methods, such as FT-IR spectroscopy, UV-vis, CHN elemental analysis, SEM, TEM, ICP-OES, EPR and XPS. The contact time to obtain equilibrium for maximum adsorption was 15 min. EPR and XPS of the Mn ions evidenced that most of the covalently bonded active sites of the nano-adsorbent are in the form of Mn(iii) ions. The heterogeneous Mn(iii) ions were found to be an effective adsorbent for the removal of methyl orange ions from solution. The adsorption process was spontaneous and endothermic in nature and followed a pseudo-second-order kinetic model. This journal is © the Partner Organisations 2014. Source


A one-pot, efficient, and straightforward procedure for the copper-catalyzed synthesis of 1,4-disubstituted 1,2,3-triazoles is studied by in situ generation of aryl azides via the reaction of aryldiazonium silica sulfates and sodium azide, followed by coupling with a terminal alkyne. These reactions are carried out in water at room temperature without using any additional ligands. © 2012 Elsevier Ltd. All rights reserved. Source


Arshadi M.,Islamic Azad University at Fasa | Amiri M.J.,Fasa University | Gil A.,Public University of Navarra
Journal of Colloid and Interface Science | Year: 2014

This paper reports the preparation of three new Schiff base ligands modified SiO2Al2O3 mixed oxide adsorbents, and their use for removal of Pb(II) and Cd(II) from aqueous solutions. Equilibrium and kinetic models for Pb(II) and Cd(II) sorption were applied by considering the effect of the contact time, initial Pb(II) and Cd(II) concentrations, effect of temperature, and initial pH. The contact time to attain equilibrium for maximum adsorption was 120min. These heterogeneous Schiff base ligands were found to be effective adsorbents for the removal of heavy metal ions from solution, with Si/Al-pr-NH-et-Npyridine-2-carbaldehyde having a high adsorption capacity for Pb(II) and Cd(II) ions from aqueous solution. The adsorption of heavy metal ions has been studied in terms of pseudo-first- and -second-order kinetics, and the Freundlich, Langmuir and Langmuir-Freundlich isotherms models have also been used to the equilibrium adsorption data. The adsorption kinetics followed the mechanism of the pseudo-second-order equation for all systems studied, confirming chemical sorption as the rate-limiting step of adsorption mechanisms and not involving mass transfer in solution, which were confirmed by techniques of DS UV-vis and FT-IR. The thermodynamic parameters (δG, δH and δS) indicated that the adsorption of Pb(II) and Cd(II) ions were feasible, spontaneous and endothermic between 25 and 80°C. © 2014 Elsevier Inc. Source


Arshadi M.,Islamic Azad University at Fasa | Salimi Vahid F.,Mapua Institute of Technology | Salvacion J.W.L.,Mapua Institute of Technology | Soleymanzadeh M.,Mapua Institute of Technology
Applied Surface Science | Year: 2013

In this study, the application of a functional ferrocene (ferrocenecarboxaldehyde) firmly heterogenized over a modified nano-size SiO2-Al2O3 mixed-oxides was reported as a novel adsorbent for the removal of methyl orange from aqueous solution. SiO 2-Al2O3 mixed-oxides was functionalized with 3-aminopropyl-triethoxysilane (3-APTES) group and ferrocenecarboxaldehyde covalently linked on this organo-functionalized SiO2-Al 2O3 mixed-oxides support. The synthesized materials were characterized by FT-IR spectroscopy, UV-vis, CHN elemental analysis, BET, TGA, ICP-MS, TEM, and XPS. The contact time to obtain equilibrium for maximum adsorption was 50 min. XPS of Fe ions evidenced that most of the active sites of the nano-adsorbent is in the form of Fe3+ ions at the surface. The heterogeneous Fe3+ ions were found to be effective adsorbent for the removal of dyes from solution. The adsorption of methyl orange ions has been studied in terms of pseudo-first-order and pseudo-second-order kinetics, and the Freundlich, Langmuir, and Langmuir-Freundlich isotherm models have also been applied to the equilibrium adsorption data. The adsorption process was spontaneous and endothermic in nature and followed pseudo-second-order kinetic model. ©2013 Elsevier B.V. All rights reserved. Source


Habibi D.,Bu - Ali Sina University | Faraji A.R.,Bu - Ali Sina University | Arshadi M.,Islamic Azad University at Fasa | Fierro J.L.G.,CSIC - Institute of Catalysis
Journal of Molecular Catalysis A: Chemical | Year: 2013

In the present study, heterogeneous Fe-nano-catalyst has been covalently anchored on a modified nanoscale SiO2/Al2O3. The synthesized materials were characterized by FT-IR spectroscopy, DS UV-vis, CHN elemental analysis, BET, EDS, SEM, TEM, TGA and XPS. The catalytic activity of the Fe nano-catalyst (FNC) in the oxidation of ethylbenzene, cyclohexene, and benzylalcohol was studied using tert-butyl hydroperoxide as oxygen source, without the need of any solvent. Oxidation of ethylbenzene, cyclohexene, and benzylalcohol catalyzed by (FNC) gave acetophenone, 2-cyclohexene-1-one and benzaldehyde, respectively, as major products. A suitable reaction condition has been optimized for Fe-nano-catalyst by considering the effect of various parameters such as reaction time and the amount of oxidant, different solvents, concentration of substrate for the maximum conversion of substrates and high selectivity. This catalyst can be easily prepared from inexpensive, commercially available reagent and is stable and reusable for oxidation of ethylbenzene, cyclohexene, and benzylalcohol. © 2013 Elsevier B.V. Source

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