Search for: hydrogen-peroxide
Total 76 records
Horseradish peroxidase immobilization on amine functionalized carbon nanotubes: direct electrochemistry and bioelectrocatalysis, Article Progress in Reaction Kinetics and Mechanism ; Volume 37, Number 2 , 2012 , pp. 161-172 ; Ghourchian, H. (Hedayatollah) ; Gholami, M. R. (Mohammad Reza) ; Rafieepour, H. A. (Hossain Ali) ; Sharif University of Technology
Horseradish peroxidase (HRP) was successfully immobilized on amine functionalized TiO2-coated multiwalled carbon nanotubes (NH2 – TiO2 – CNTs) by a convenient and efficient method. Electrochemical impedance spectroscopy, cyclic voltammetry and amperometry were applied to characterize the HRP/NH2 – TiO2 – CNT nano-composite. These techniques showed that the NH2 – TiO2 – CNTs greatly enhance the electron transfer between HRP and the modified electrode. Owing to the redox reaction of the electroactive centre of HRP, the HRP = NH2 – TiO2 – CNTs modified electrode exhibited a pair of quasi-reversible peaks with a peak-to-peak separation (ΔEp) of 70.6 mV and a formal potential (E 0′) of 367.65 mV...
Transition metal free oxidation of alcohols to carbonyl compounds using hydrogen peroxide catalyzed with LiCl on montmorillonite K10, Article Acta Chimica Slovenica ; Volume 54, Issue 3 , 2007 , Pages 635-637 ; 13180207 (ISSN) ; Khalili, B ; Abdollahifar, A ; Hashemi, M. M ; Sharif University of Technology
Alcohols have been successfully converted into their corresponding carbonyl compounds using hydrogen peroxide catalyzed by lithium chloride on montmorillonite K10. Clay supported lithium chloride can be recovered after using as catalyst for oxidation of alcohols. The future runs according to this procedure showed no considerable decrease in the reaction yield and catalyst effect
Oxidation of benzylic alcohols to carbonyl compounds with hydrogen peroxide catalysed by manganeses chloride supported on montmorillonite K10, Article Journal of Chemical Research ; Issue 8 , 2005 , Pages 484-485 ; 03082342 (ISSN) ; Khalili, B ; Eftekhari-sis, B ; Sharif University of Technology
Scientific Reviews Ltd 2005
Manganeses(II) chloride supported on montmorillonite K10 was found to be an efficient catalysts for the oxidation of alcohols to carbonyl compounds with hydrogen peroxide as oxidant
Efficient oxidation of olefins and sulfides catalyzed by manganese(III)-tridentate Schiff base complex using UHP as oxidant, Article Catalysis Communications ; Volume 9, Issue 7 , 2008 , Pages 1600-1606 ; 15667367 (ISSN) ; Tahsini, L ; Latifi, R ; Sharif University of Technology
Catalytic studies were performed to develop a simple oxidation system for olefins and sulfides using manganese(III)-tridentate Schiff base complex, Mn(N-OPh-sal)(acac)(EtOH) (N-HOPh-Hsal = N-hydroxyphenyl-salicyldienamine, Hacac = acetylacetone), and urea-hydrogen peroxide (UHP) as terminal oxidant. Conversions up to 90% for olefins at 0 °C and 96% for sulfides at room temperature as well as sulfoxide selectivity up to 73% were achieved in short reaction times. Also this study confirms the accelerating effect of strong π-donor axial ligands such as imidazole (ImH) on the oxidation reactions. © 2008 Elsevier B.V. All rights reserved
Catalytic activity of manganese(III)-oxazoline complexes in urea hydrogen peroxide epoxidation of olefins: The effect of axial ligands, Article Journal of Molecular Catalysis A: Chemical ; Volume 260, Issue 1-2 , 2006 , Pages 163-169 ; 13811169 (ISSN) ; Latifi, R ; Tahsini, L ; Sharif University of Technology
The catalytic activity of two manganese(III)-oxazoline complexes [Mn(phox)2(CH3OH)2]ClO4 and Mn(phox)3 (Hphox = 2-(2′-hydroxylphenyl)oxazoline), was studied in the epoxidation of various olefins. All of epoxidation reactions were carried out in (1:1) mixture of methanol:dichloromethane at room temperature using urea hydrogen peroxide (UHP) as oxidant and imidazole as co-catalyst. The epoxide yields clearly demonstrate the influence of steric and electronic properties of olefins, the catalysts and nitrogenous bases as axial ligand. [Mn(phox)2(CH3OH)2]ClO4 catalyst with low steric properties has higher catalytic activity than Mn(phox)3. The highest epoxide yield (95%) was achieved for indene...
M.Sc. Thesis Sharif University of Technology ; Seifkordi, Ali Akbar ; Bazmi, Mansour ; Ghaedian, Maryam
Due to increasing environmental concern, special interest has been paid to reduction of organosulfur compounds in transportaion fuels. The sulfur- containing compounds are converted into sulfur oxide, i.e, SOx , during combustion, which is a major source of acid rain and air pollution.Gas condensate is a mixture consisting primarily of pentanes and heavier hydrocarbons which is recovered as a liquid from natural gas. It is a proper hydrocarbon source for producing gasoline, kerosene and gas oil in refineries. In this reseach a gas condensate was used as feedstock for studing oxidative desulfurization (ODS). The influence of various parameters of desulforization including the reaction...
Article Journal of Sulfur Chemistry ; Volume 32, Issue 4 , 2011 , Pages 335-343 ; 17415993 (ISSN) ; Zare, M ; Sharif University of Technology
The oxidation of sulfides to sulfoxides with hydrogen peroxide in good yield and high selectivity has been catalyzed very effectively by a series of Schiff base salen-type iron complexes in a monophasic medium (CH 2Cl2/CH3OH) at ambient temperature. The results of the present study show that the reaction rate strongly depends on both catalyst steric effects and steric and electronic properties of sulfides. In the system, the electronic spectral studies are applied to explain the formation of a reactive (salen) Fe=O intermediate
Synthesis, X-ray structure and study of a mixed ligand iron(III) complex with tridentate Schiff base as a homogeneous catalyst in the efficient oxidation of sulfides, Article Inorganic Chemistry Communications ; Volume 12, Issue 6 , 2009 , Pages 476-480 ; 13877003 (ISSN) ; Tahsini, L ; Latifi, R ; Amani, V ; Ellern, A ; Keith Woo, L ; Sharif University of Technology
A mononuclear mixed ligand complex of iron, [FeIII(N-OPh-sal)(acac)EtOH], where Hacac and N-HOPh-Hsal denote acetylacetone and N-hydroxyphenyl-salicylideneamine, respectively, has been synthesized and characterized by elemental analysis, spectral studies and X-ray crystallography. The catalytic system containing this complex and urea hydrogen peroxide as oxidizing agent was used to selectively oxidize a range of sulfides to the corresponding sulfoxides in good yields under mild conditions. The electronic spectra of the catalytic system were applied to explore reactivity and stability of the catalyst during sulfide oxidation reactions and to examine the nature of active species, as well. ©...
A novel binuclear iron(III)-salicylaldazine complex; synthesis, X-ray structure and catalytic activity in sulfide oxidation, Article Polyhedron ; Volume 183 , June , 2020 ; Bagherzadeh, M ; Amini, M ; Akbari, A ; Ellern, A ; Woo, L. K ; Sharif University of Technology
Elsevier Ltd 2020
A novel binuclear iron(III)-salicylaldazine complex has been synthesized and characterized by various techniques such as IR and UV–Vis spectroscopy and X-ray crystallography. The catalytic oxidation of sulfides in the presence of the aforementioned complex was explored at room temperature using urea hydrogen peroxide (UHP) as an oxidant. Effects of different reaction conditions consisting catalyst and oxidant amount, solvent effect and reaction time on the catalytic activity and selectivity in the reaction of methylphenylsulfide oxidation has been surveyed. Perfect selectivity toward sulfoxide was achieved after 15 min in CH3CN by choice of a properly optimized reaction condition. © 2020...
Article 2008 AIChE Annual Meeting, AIChE 100, Philadelphia, PA, 16 November 2008 through 21 November 2008 ; November , 2008 ; 9780816910502 (ISBN) ; Ebrahimi, A. A ; Shahalami, S ; Sharif University of Technology
Article Chinese Chemical Letters ; Volume 18, Issue 12 , December , 2007 , Pages 1451-1454 ; 10018417 (ISSN) ; Najafi, G. R ; Hashemi, M. M ; Sharif University of Technology
Oximes were oxidized to the corresponding carbonyl compounds in good to high yields by environmentally friendly and green oxidant, H2O2 catalyzed by montmorillonite K-10 supported cobalt(II) chloride. © 2007 Ali Ezabadi
Article CHISA 2006 - 17th International Congress of Chemical and Process Engineering, Prague, 27 August 2006 through 31 August 2006 ; 2006 ; 8086059456 (ISBN); 9788086059457 (ISBN) ; Aminshahidi, B ; Meraj, F ; Sharif University of Technology
Gelatin is a denatured protein derived from collagen by thermohydrolysis and has a rheological property of thermo reversible transformation between sol & gel. Gelatin is one of the most important biopolymers, with widespread applications in the food, pharmaceutical, cosmetic and photographic industries. Gelatin is commercially made from skins and skeletons of bovine and porcine and mammalian gelatin has been intensively studied. However, mammalian gelatin is at risk for contamination with bovine spongiform encephalopathy and increase in demand for kosher and halal foods have created a demand for fish gelatin for food applications. Therefore, the objective of this study was to extract gelatin...
Novel oxidation of phenols to quinones by hydrogen peroxide in the presence of cobalt(II) and manganese(II) acetate, Article Acta Chimica Slovenica ; Volume 50, Issue 3 , 2003 , Pages 569-572 ; 13180207 (ISSN) ; Ahmadibeni, Y ; Sharif University of Technology
Hydrogen peroxide readily oxidizes phenols to the corresponding quinones in the presence of cobalt(II) acetate or manganese(II) acetate as catalyst
Aromatization of Hantzsch 1,4-dihydropyridines by hydrogen peroxide in the presence of cobalt(II) acetate, Article Monatshefte fur Chemie ; Volume 134, Issue 1 , 2003 , Pages 107-110 ; 00269247 (ISSN) ; Ahmadibeni, Y ; Ghafuri, H ; Sharif University of Technology
Hydrogen peroxide readily oxidizes Hantzsch type 1,4-dihydropyridines in the presence of cobalt(II) acetate as catalyst at room temperature. No evidence of a dealkylation process for 4-alkyl 1,4-dihydropyridines has been observed
Synthesis, crystal structure and catalytic activity of a novel Mo(VI)-oxazoline complex in highly efficient oxidation of sulfides to sulfoxides by urea hydrogen peroxide, Article Inorganica Chimica Acta ; Volume 361, Issue 7 , 2008 , Pages 2019-2024 ; 00201693 (ISSN) ; Tahsini, L ; Latifi, R ; Ellern, A ; Woo, L. K ; Sharif University of Technology
Elsevier S.A 2008
Novel molybdenum complex, cis-[MoO2(phox)2] has been synthesized and characterized by IR, 1H NMR, elemental analyses (CHN), and X-ray molecular structure determination methods. This complex was found to be an efficient, selective catalyst for the oxidation of various sulfides to sulfoxides with urea hydrogen peroxide (UHP) in excellent yields (100% for diallylsulfide) and short reaction times (20 min) at room temperature. The catalytic system oxidizes diallylsulfide chemoselectively to its corresponding sulfoxide without any over oxidation in double bond. © 2007 Elsevier B.V. All rights reserved
Article Journal of Applied Sciences ; Volume 8, Issue 6 , 2008 , Pages 1108-1112 ; 18125654 (ISSN) ; Ghaneian, M. T ; Hashemian, S. J ; Moussavi, G ; Khavanin, A ; Ghanizadeh, G ; Sharif University of Technology
Asian Network for Scientific Information 2008
Photo-oxidation of dyes is a new concern among researchers since it offers an attractive method for decoloration of dyes and breaks them into simple mineral forms. An advanced oxidation process, UV/H2O2, was investigated in a laboratory scale photoreactor for decolorization of the Reactive blue 19 (RB19 dye from synthetic textile wastewater. The effects of operating parameters such as hydrogen peroxide dosage, pH, initial dye concentration and UV dosage, on decolorization have been evaluated. The RB19 solution was completely decolorized under optimal hydrogen peroxide dosage of 2.5 mmol L-1 and low-pressure mercury UV-C lamps (55 w) in less than 30 min. The decolorization rate followed...
Theoretical Investigation of Adsorption & Reactions of H2 , O2&HCO2H on Single Crystal Alloys Surfaces Based on UBI-QEP Method, M.Sc. Thesis Sharif University of Technology ; Gobal, Fereydoon
The aim of this project is to investigate the mechanisms of absorption and reactions of H2, O2, HCO2H on the single crystal surfaces of transition metals alloys such as Ni-Cu and Ni-Fe and …as well as the ability to control the properties of the mentioned alloys with change in constitutions percentage. In order to achieve the objectives, Unity Bond Index-Quadratic Exponential Potential, UBI-QEP method have been employed. Using this method, the thermodynamic parameters (heat of adsorption and reaction enthalpy changes) and kinetic parameters (activation energy of the reaction) can be calculated, and using these results, intermediate, and as a result, the mechanism of heterogeneous catalytic...
M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr ; Shamloo, Amir
Design, simulation, optimization and manufacturing of an enzyme-based microfluidic biosensor has been carried out during this research to measure histamine concentration in a sample. The designed biosensor is composed of a micro-bioreactor to degrade histamine and yield hydrogen peroxide, and a chemical reactor to measure the amount of hydrogen peroxide, using chemiluminescence methods. The geometry of the bioreactor and chemical reactor is developed through comparison and optimization of several different geometries. In theory, the designed sensor can determine histamine concentration in a range of 10M to 1mM under one minute, with a maximum error of 5%. Designed biosensor is built using...
Solphate Leaching of Titanium Minerals from Shore Reservoir of in the North of Iran and Refining of Iron and other Impurities, M.Sc. Thesis Sharif University of Technology ; Yoozbashizadeh, Hossein
The most important raw material for production of titanium dioxide is titanium that used in Aerospace, Plastic, Pigment and Pharmacy industries. Due to the presence of titanium minerals in Iran, reduce imports of titanium dioxide is one of the goals of the Ministry of Industries and Mines to achieve self-sufficiency in the production of TiO2.One of the very rich sources of titanium is alluvial sands in northern of Iran. In this study the TiO2 high grade pigment production from these sources has been investigated. Titanium-bearing sands with 9.5% TiO2 are used to produce high grade TiO2 pigment. After magnetic separation stage and reach a purity of 16.2% TiO2, upgrading slag step is not...
M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad
This thesis contains two parts .In the first part a catalyst such as AlCl3/Al20 has been demonstrated to catalyze Michael addition reaction of amines to a,�- unsaturated compounds with high yields , short reaction time and under solvent-free condition.The Michael addition to a,�- unsaturated compounds produces quantitively the mono addition products.The next part is about olefins epoxidation . Alkene epoxidation is a useful reaction in organic synthesis. Epoxides play an important role in industrial intermediates for the production of fine chemicals as well as pharmaceuticals .The hydrogen peroxide has been used as an oxidant because it is considered as an economical and appropriate reagent...