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Biodiesel Production from Used Sunflower Oil Via Transesterification Using Green Solid Nanocatalysts Derived from Animal Bone Support
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samahe Sadat (Supervisor)
Abstract
This project evaluates the feasibility of using waste salmon fish bones as the reusable and low cost solid catalyst support for synthesis of biodiesel from waste sunflower oil via transestrification method. Calcinated waste fish bone derived hydroxyapatite (HAP) was employed as the supporter for KOH & K2CO3 to prepare an efficient solid base catalyst for biodiesel production. The catalyst were characterized by SEM-EDS, XRD, FTIR, BET, TGA, ICP. The effects of catalyst preparation conditions (such as fish bone and KOH or K2CO3 calcination temperature, loading of KOH or K2CO3 on the support), reaction conditions (such as reaction time, methanol/oil molar ratio, reaction temperature and...
The modeling of kinetics and catalyst deactivation in propane dehydrogenation over Pt-Sn/γ-Al2O3 in presence of water as an oxygenated additive
, Article Petroleum Science and Technology ; Vol. 32, issue. 10 , Mar , 2014 , pp. 1139-1149 ; ISSN: 10916466 ; Fattahi, M ; Khorasheh, F ; Sharif University of Technology
Abstract
A reduction in catalyst's activity with time-on-stream and the formation of side products are two of the problems associated with catalytic propane dehydrogenation (PDH). Previous studies have indicated that the presence of small amounts of oxygenated additives such as water can reduce coke formation and enhance catalyst activity. The aim of the present work was to develop an appropriate kinetic model for PDH over a commercial Pt-Sn/γ-Al 2O3 catalyst in the presence of small amounts of water. Experimental data were obtained from a previous study where catalytic PDH was carried out in a bench scale reactor system at atmospheric pressure in the temperature range of 575-620°C in the presence of...
Reaction kinetics investigation of 1-fluoro-2,4-dinitrobenzene with substituted anilines in ethyl acetate-methanol mixtures using linear and nonlinear free energy relationships
, Article Journal of Physical Organic Chemistry ; Volume 24, Issue 11 , 2011 , Pages 1095-1100 ; 08943230 (ISSN) ; Harifi Mood, A. R ; Gholami, M. R ; Sharif University of Technology
Abstract
Aromatic nucleophilic substitution reaction of 1-fluoro-2,4-dinitrobenzene with para-substituted and meta-substituted anilines was kinetically investigated in the mixtures of ethyl acetate and methanol at room temperature. The correlation of second-order rate coefficients with Hammett's substituent constants yields a fairly linear straight line with negative slope in different mole fractions of ethyl acetate-methanol mixtures. The measured rate coefficients of the reaction demonstrated a dramatic variation in ethyl acetate-methanol mixtures with the increasing mole fraction of ethyl acetate. Linear free energy relationship (LFER) investigations confirm that polarity has a major effect on the...
Effect of CO2 partial pressure on the thermal decomposition kinetics of zinc carbonate hydroxide
,
Article
International Journal of Engineering, Transactions B: Applications
;
Volume 24, Issue 3
,
2011
,
Pages 263-268
;
1728-144X (ISSN)
; Halali, M
; Nobari, A. H
;
Sharif University of Technology
Abstract
In this work, the effect of carbon dioxide partial pressure on the calcination kinetics of high purity zinc carbonate hydroxide has been studied. Non-isothermal analysis has been performed on samples at different CO 2 partial pressures by TGA and DTA. It has been found that the calcination behaviour of this material corresponds to the shrinking core model and the reaction mechanism is phase boundary controlled. The calcination reaction of zinc carbonate hydroxide starts at 240 °C. Increasing the carbon dioxide partial pressure can result in an increase in the reaction start temperature of up to 30°C. The activation energy for the reaction is calculated as 180 ± 5 kJ/mol at...
Cellulose-immobilized NHC-Cu(i) complex: An efficient and reusable catalyst for multicomponent synthesis of 1,2,3-triazoles
, Article RSC Advances ; Volume 5, Issue 120 , Nov , 2015 , Pages 99498-99501 ; 20462069 (ISSN) ; Habibi, Z ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
A novel cellulose supported copper NHC complex has been prepared by the reaction of cellulose supported imidazolium salt with copper(i) iodide. The catalyst is active in the synthesis of 1,2,3-triazoles via a one-pot reaction of alkyl/benzyl halides or tosylates and terminal alkynes, with sodium azide in water
Synthesis, characterizations and catalytic studies of a new two-dimensional metal-organic framework based on Co-carboxylate secondary building units
, Article Journal of Solid State Chemistry ; Volume 223 , March , 2015 , Pages 32-37 ; 00224596 (ISSN) ; Ashouri, F ; Daković, M ; Sharif University of Technology
Academic Press Inc
2015
Abstract
A metal-organic framework [Co3(BDC)3(DMF)2(H2O)2] was synthesized and structurally characterized. X-ray single crystal analysis revealed that the framework contains a 2D polymeric chain through coordination of 1,4-benzenedicarboxylic acid linker ligand to cobalt centers. The polymer crystallize in monoclinic P21/n space group with a=13.989(3) Å, b=9.6728(17) Å, c=16.707(3) Å, and Z=2. The polymer features a framework based on the perfect octahedral Co-O6 secondary building units. The catalytic activities of [Co3(BDC)3(DMF)2(H2O)2]n for olefins oxidation was conducted. The heterogeneous catalyst could be facilely separated from the reaction mixture, and reused three times without significant...
Mathematical modeling of a slurry bubble column reactor for hydrodesulfurization of diesel fuel: Single- and two-bubble configurations
, Article Chemical Engineering Research and Design ; Volume 100 , August , 2015 , Pages 362-376 ; 02638762 (ISSN) ; Yaghmaei, S ; Fattahi, M ; Mashayekhan, S ; Hosseini Ardali, S. M ; Sharif University of Technology
Institution of Chemical Engineers
2015
Abstract
In this investigation, a mathematical model for HDS of diesel fuel in a slurry bubble column reactor was developed. The model is based on the axial dispersion of the heterogeneous gas flow regime, which includes two various bubble classes: large (20±70mm) and small (1±10mm). By assuming only large or large plus small bubbles in the column, single- and two-bubble class mode equations are developed. The developed models to solving the mass and enthalpy balances from which the sulfur conversion was obtained that undertaken. The chemical kinetics over NiMoS/γ-Al2 O3 catalyst were undertaken for the reaction rate of the involved reactions. The reactor operating conditions...
Enhanced visible light photocatalytic activity of nano-biocl/bivo4/zeolite p-n heterojunction and ag/biocl/bivo4 hybrid
, Article Materials Research Innovations ; 2016 , Pages 1-7 ; 14328917 (ISSN) ; Gholizadeh Khasevani, S ; Rahman Setayesh, S ; Gholami, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2016
Abstract
Visible light-active BiOCl/BiVO4/mordenite and Ag/BiOCl/BiVO4 nanocomposite with a p–n heterojunction structure were prepared. Mordenite nanocrystals were synthesised using the hydrothermal method. Deposition and reduction methods were utilised to modify the Zeolite surface. The photocatalytic activities of the heterojunctions were investigated by scanning the change of Acid blue 92 (AB92) concentration under visible irradiation. The nanocomposites demonstrated improved efficiency for dye photodegradation. The activities are due to strong oxidative ability and efficient charge separation and transfer through the BiOCl/BiVO4 p–n junction. The photogenerated electron-holes react with species...
DM Water Plant Sedimentation as a Cheap and Waste Source of Catalyst for Biodiesel Production
, Article International Journal of Chemical Reactor Engineering ; Volume 14, Issue 1 , 2016 , Pages 113-124 ; 15426580 (ISSN) ; Mohadesi, M ; Hosseini, S ; Davood Beygi, Y ; Moradi, R ; Sharif University of Technology
Walter de Gruyter GmbH
Abstract
Transesterification reaction was performed in the presence of soybean oil, methanol, and Demineralized water plant sedimentation catalyst at 60°C for 8 h in this study. Central composite design method was used to study the effect of catalyst concentration and methanol to oil molar ratio on purity and yield of produced biodiesel. The results showed catalyst concentration of 9.08 wt% and methanol to oil molar ratio of 22.49 as the optimum condition in which the values of purity and yield of the produced biodiesel in the second-order models were 99.89% and 81.83%, respectively. Experiments are in good agreement with the mentioned values as corresponded values are 99.95% and 86.68%,...
Kinetic modelling of enzymatic biodiesel production from castor oil: Temperature dependence of the Ping Pong parameters
, Article Canadian Journal of Chemical Engineering ; Volume 94, Issue 3 , 2016 , Pages 512-517 ; 00084034 (ISSN) ; Kariminia, H. R ; Khorasheh, F ; Sharif University of Technology
Wiley-Liss Inc
2016
Abstract
Biodiesel is considered an alternative replacement for petroleum diesel, and enzymatic reaction is one method for biodiesel production. Understanding the kinetics of this reaction is important to achieve higher production rates. The kinetics of transesterification of castor oil using Novozym 435 was investigated in this study. The genetic algorithm was employed for estimation of kinetic parameters including Vmax, KmTG, and KmA in the Ping Pong kinetic model at different temperatures. In most enzymatic reactions that follow the Ping Pong mechanism, inhibition by alcohol has been taken into consideration. Here, we examined a competitive inhibition mechanism and found no inhibition effect at...
Nano cobalt ferrite catalyzed coupling reaction of nitroarene and alkyl halide: An odorless and ligand-free rout to unsymmetrical thioether synthesis
, Article Catalysis Communications ; Volume 94 , 2017 , Pages 33-37 ; 15667367 (ISSN) ; Pourkaveh, R ; Sharif University of Technology
Elsevier B.V
2017
Abstract
This study describes an odorless protocol for the synthesis of unsymmetrical sulfides via cobalt ferrite (CoFe2O4) catalyzed cross-coupling reaction of nitroarenes with alkyl halides in the presence of thiourea as sulfur source under ligand-free conditions. The catalyst was recycled using external magnetic field and reused for ten consecutive runs in the reaction of nitrobenzene, thiourea and benzyl bromide without significant loss of activity. Apart from being magnetically separable, being inexpensive and air-stable are another important features of this catalytic system. All the products were formed in good yields and short reaction times. © 2017 Elsevier B.V
M: XNi100- X (M = Ag, and Co) nanoparticles supported on CeO2 nanorods derived from Ce-metal organic frameworks as an effective catalyst for reduction of organic pollutants: Langmuir-Hinshelwood kinetics and mechanism
, Article New Journal of Chemistry ; Volume 41, Issue 19 , 2017 , Pages 10948-10958 ; 11440546 (ISSN) ; Gholami, M. R ; Sharif University of Technology
Royal Society of Chemistry
2017
Abstract
In this study, AgxNi100-x, and CoxNi100-x (x = 0, 20, 40, 60, 80, and 100) bimetallic nanoparticles were successfully decorated on the surface of CeO2 nanorods derived from Ce-metal organic frameworks (Ce-MOF). The as-synthesized products were characterized using different techniques including XRD, FE-SEM, EDX, TEM, ICP, and BET. The as-prepared nanocomposites showed remarkable catalytic activity towards the reduction of organic pollutants such as 4-nitrophenol (4-NP), and rhodamine-B dye (RhB) by NaBH4 solution, with high stability and reusability for five consecutive cycles. The obtained results indicated that among these nanocomposites, Ag80Ni20@CeO2, and Co60Ni40@CeO2 exhibited the best...
Immobilization of nickel ions onto the magnetic nanocomposite based on cross-linked melamine groups: effective heterogeneous catalyst for N-arylation of arylboronic acids
, Article Applied Organometallic Chemistry ; Volume 32, Issue 2 , February , 2018 ; 02682605 (ISSN) ; Keshavarzi, N ; Matloubi Moghaddam, F ; Hosseini, S. H ; Sharif University of Technology
John Wiley and Sons Ltd
2018
Abstract
A new magnetic heterogeneous catalyst was synthesized by immobilization of nickel ions onto a cross-linked polymeric nanocomposite composed of cyanuric chloride, ethylenediamine and functionalized magnetic nanoparticles. The resulting nitrogen rich support was capable of adsorbing large amounts of nickel ions (1.20 mmol g−1). The synthesized catalyst was characterized using AAS, TEM, FT-IR, EDX, TGA, SEM, BET and XRD techniques. The performance of the prepared catalyst was investigated in the C-N coupling of arylamines with aryl boronic acids. The reaction was carried out under a mild condition and good to moderate to good yields of products was obtained using only 5.0 mol% of the catalyst....
Enhanced visible light photocatalytic activity of nano-BiOCl/BiVO4/Zeolite p-n heterojunction and Ag/BiOCl/BiVO4 hybrid
, Article Materials Research Innovations ; Volume 22, Issue 3 , 2018 , Pages 137-143 ; 14328917 (ISSN) ; Gholizadeh Khasevani, S ; Rahman Setayesh, S ; Gholami, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
Visible light-active BiOCl/BiVO4/mordenite and Ag/BiOCl/BiVO4 nanocomposite with a p–n heterojunction structure were prepared. Mordenite nanocrystals were synthesised using the hydrothermal method. Deposition and reduction methods were utilised to modify the Zeolite surface. The photocatalytic activities of the heterojunctions were investigated by scanning the change of Acid blue 92 (AB92) concentration under visible irradiation. The nanocomposites demonstrated improved efficiency for dye photodegradation. The activities are due to strong oxidative ability and efficient charge separation and transfer through the BiOCl/BiVO4 p–n junction. The photogenerated electron-holes react with species...
Synthesis of “L-cysteine–graphene oxide” hybrid by new methods and elucidation of its uptake properties for Hg(II) ion
, Article Separation Science and Technology (Philadelphia) ; Volume 53, Issue 6 , 2018 , Pages 843-855 ; 01496395 (ISSN) ; Outokesh, M ; Akbari, A ; Kosari, M ; Tayyebi, A ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
This study introduces two new, simple, and scalable methods for synthesis of “cysteine–graphene oxide” hybrid, namely nucleophilic and covalent methods. Produced adsorbents could uptake 500 and 600 mg Hg2+/g, respectively, which are larger than capacities of most of the commercial adsorbents. By means of different instrumental techniques, chemical structures of the obtained graphene products were disclosed, and two pertinent mechanisms for their formations were suggested. Time for attaining uptake equilibrium for nucleophilic/covalent samples was 30 min/150 min, and kinetics was controlled by liquid film resistance/chemical reaction mechanisms, respectively. High selectivity and good...
Simulation study of Conventional Fire Flooding (CFF) in fractured combustion cells: A promising tool along experiment
, Article 1st International Petroleum Conference and Exhibition, Shiraz, 4 May 2009 through 6 May 2009 ; 2009 ; Kharrat, R ; Ghotbi, C ; Sharif University of Technology
European association of geoscientists and engineers, EAGE
2009
Abstract
The Conventional Fire Flooding (CFF) process application feasibility on fractured carbonated reservoirs remained questionable. In this paper first combustion parameters and reaction kinetics of a naturally fractured low permeability carbonated heavy oil reservoir in Iran called Kuh-E-Mond applied to simulation study. After that, simulator has been validated with Kuh-E-Mond combustion tube experiment. Recovery mechanism in single block matrix is different from one in conventional model since oxygen first flows into the fractures and then diffuses from all sides into the matrix. Combustion of the oil in the fractures produces some water ahead of fracture combustion front which prohibits oxygen...
Factors affecting platinum extraction from used reforming catalysts in iodine solutions at temperatures up to 95 °C
, Article Hydrometallurgy ; Volume 97, Issue 1-2 , 2009 , Pages 119-125 ; 0304386X (ISSN) ; Baghalha, M ; Sharif University of Technology
2009
Abstract
Platinum extraction from the spent reforming catalysts in iodine-iodide solutions at temperatures from 25 to 95 °C was investigated. The reforming catalyst mostly consists of a porous gamma alumina support with metallic platinum finely dispersed on the walls of the nano-pores of the catalyst support. The effect of a variety of factors, including catalyst particle size, impeller agitation speed, reactant concentrations, liquid to solid mass ratio, temperature and the solution pH on the Pt extraction rate and recovery were investigated. It was found that the catalyst particle sizes less than 106 μm and impeller agitation speed higher than 700 rpm eliminated the effects of catalyst size and...
Mechanism of reaction of molten NiTi with EBM graphite crucible
, Article Materials Science and Technology ; Volume 25, Issue 6 , 2009 , Pages 699-706 ; 02670836 (ISSN) ; Ahmadi, E ; Malekzadeh, M ; Sharif University of Technology
2009
Abstract
Ultra clean NiTi shape memory alloy was produced by electron beam melting of Ni rich vacuum inductionally melted butts together with pure Ti chunks in both condensed and electrographite crucibles. A hollow cathode discharge gun was used for heating up to 1623, 1653 and 1693 K and holding the charge materials under vacuum for 300, 600, 900 and 1200 s. Effects of temperature, time and compactness of the crucible on formation/disappearance of the hard compounds like Ni3Ti, Ti4Ni2O, Ti4Ni 2C, Ti3Ni2OC and TiC were determined by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray analysis. A combination of the experimental results with the kinetic rate equations indicated...
Kinetics study of a Diels-Alder reaction in mixtures of an ionic liquid with molecular solvents
, Article Journal of Physical Organic Chemistry ; Volume 21, Issue 9 , 2008 , Pages 783-788 ; 08943230 (ISSN) ; Habibi Yangjeh, A ; Gholami, M. R ; Sharif University of Technology
2008
Abstract
The second-order rate constants for cycloaddition reaction of cyclopentadiene with naphthoquinone were determined spectrophotometrically in various compositions of 1-(1-butyl)-3-methylimidazolium terafluoroborate ([bmim]BF4) with water and methanol at 25°C. Rate constants of the reaction in pure solvents are in the order of water > [bmim]BF 4 > methanol. Rate constants of the reaction decrease sharply with mole fraction of the ionic liquid in aqueous solutions and increase slightly to a maximum in alcoholic mixtures. Multi-parameter correlation of logk 2 versus solute-solvent interaction parameters demonstrated that solvophobicity parameter (Sp), hydrogen-bond donor acidity (α) and...
Mathematical modeling of human blood clotting formation
, Article 6th International Special Topic Conference on ITAB, 2007, Tokyo, 8 November 2007 through 11 November 2007 ; 2007 , Pages 273-276 ; 9781424418688 (ISBN) ; Jahed, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2007
Abstract
Over the last two decades, mathematical modeling has become a popular tool in study of blood coagulation. This paper describes the coagulation pathway and presents a mathematical model for the generation of blood clot in human vasculature. Parameters of interest in this study include procoagulants and anticoagulants whose activity may be enhanced by various activator enzymes. The process of human blood clotting involves a complex interaction between these parameters and continuous time and state processes. In this work, we propose to model these highly inter-relational processes by a set of nonlinear chemical rate equations. We have modeled this process as a dynamical system, as chemical...