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sulfide
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Kinetic of Zinc Sulfide Roasting of
, M.Sc. Thesis Sharif University of Technology ; Halali, Mohammad (Supervisor)
Abstract
In this study, the effect of two main parameters, time and temperature, were investigated in the roasting process of zinc sulfide of Bafgh’s mine, and kinetics and the mechanism of the roasting reaction were examined, too. The oxidation process was performed in a muffle furnace in the presence of the oxygen of air atmosphere. The raw powder material (with the particle size of 74-250 micron) was poured in Alumina crucibles. The roasting process was run in eight temperatures of 650, 700, 750, 800, 850, 900, 950 and 1000 ◦C. Oxidation percent was calculated in six times of 5, 10, 15, 30, 45 and 60 minutes. The experiments were designed in a way that the effect of each parameter could be...
H2S Gas Sensing Characterization of Nano-Structured SnO2-CuO Multilayer Sensor
, M.Sc. Thesis Sharif University of Technology ; Ghorbani, Mohammad (Co-Advisor)
Abstract
Hydrogen sulfide, H2S, is a toxic gas and has detrimental effects on human health and the oil and gas industry. Therefore, its identification is very important. According to the devastating effects of this gas, then, the general mechanisms have been studied for gas detection. In addition, by highlighting the benefits of the multilayer nanostructure electrochemical sensors, an applicable and efficient method for the industrial production of these sensors has been investigated. In this regard, the sol-gel method is used to prepare the SnO2-CuO multilayer thin film and the advantages of this method was compared to PVD method. Also sensor properties of both deposition methods have been...
Fabrication of Nano Sensor for Detecting H2S
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor) ; Rashidi, Alimorad (Supervisor) ; Izadi Yazdan Abadi, Nosrat (Co-Advisor)
Abstract
Due production and use of large amount of chemical and emissions of pollutants in air, detection and control of these compounds are necessary. One of the common methods to detect these pollutants in the ambient is using metal oxide semiconductor sensors. However, these types of sensors suffer from low selectivity toward a certain compound in the mixture of different gas components. In this study, the object was to investigate the effect of different amount of CNTs on performance of tin oxide to improve their selectivity for detection of 50 ppm of hydrogen sulfide at low temperature. To perform the study, nanoparticles of pure tin oxide and SnO2 base hybrids containing 0.25wt%, 0.5wt%, 2.5wt%...
Nanocarbon-based Nanocatalyst Design & Synthesis for Hydrogen Sulfide Removal from Gas Feed
, M.Sc. Thesis Sharif University of Technology ; Baghalha, Morteza (Supervisor) ; Eskandari, Mohammad Mehdi (Supervisor)
Abstract
well known metal-free nanostructure carbon-based catalyst, mesoporous graphitic carbon nitride, with diverse morphologies were synthesized by using ethylendiamine/carbontetrachloride as a precursor, SBA-15 and SBA-15 nanorod as hard templates. We have investigated morphology effect on the catalytic performance. The catalysts were characterized by means of low angle and wide angle XRD, BET, FT-IR, CHNOS, FE-SEM analysis. Because of high surface area, pore volume and high nitrogen content, which acts as lewis basic site, for the first time, carbon nitride is chosen for selective catalytic oxidation of hydrogen sulfide to sulfure. Reaction was taken place in a fixed-bed reactor and at...
Creating a Protective Coating Against Corrosion and Erosion on the Surface of the Parts using in Sour Environments
, M.Sc. Thesis Sharif University of Technology ; Kokabi, Amir Hossein (Supervisor)
Abstract
A concern in the production sour oil and gas is the corrosion caused by the acid gas H2S. Even though corrosion resistant alloys (CRA) have long been available as a material selection option that mitigates H2S corrosion, the carbon steel is in general more cost-effective for oil and gas facilities. The aim of this study is to investigate the mechanical properties of 410NiMo cladding on a low alloy steel substrate. In this investigation, two successive layers of ER410NiMo were clad on low alloy steel substrates. To reduce the likelihood of Hydrogen Induced Cracking (HIC) and producing stable hydrogen traps, Post Weld Heat Treatment (PWHT) was used. To characterize the mechanical properties of...
Preparation of Nanocomposite Membrane For H2S / CH4 Separation
, M.Sc. Thesis Sharif University of Technology ; Mousavi, Abbas (Supervisor) ; Khanbabaee, Ghader (Supervisor) ; Babana’lbandi, Ahmad (Co-Advisor)
Abstract
Due to the presence of carbon dioxide and hydrogen sulfide in natural gas outlet of wells, it cannot be sent directly to the municipal pipelines. This study was trying to be select and made membranes for separation of CO2 and H2S from methane. Permeability of methane and carbon dioxide gases through the polyurethane membranes were studied. For this purpose, two commercial polyurethane and synthesized polyurethane with different formulations of the compounds that have been studied so far in the literature were used. Synthesized polyurethane and nano-composite membranes were characterized by using Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC) and Fourier Transfer...
Preparation of Nanocomposites from Carbon Nanostructures and Transtion Metal Oxides and their use in Preparation of Hybrid Electrochemical Capacitors
, M.Sc. Thesis Sharif University of Technology ; Shahrokhian, Saeed (Supervisor)
Abstract
In the first part, we report a new and simple procedure for preparing reduced graphene oxide /nickel, cobalt hydroxide composite (Ni,Co-OH/rGO/NF via a fast and simple two-step electrochemical method including potentiostatic routes in the presence of Cetyl trimethyl ammonium bromide )CTAB( as a cationic surfactant. In the first step, a piece of nickel foam (NF) is sonicated in a suspension of graphene oxide (GO, 6 mg/L) after dried in an oven, reduced by electrochemically. After that, Ni, Co LDH were co-deposited on the surface of rGO/NF. The resulting modified electrode afforded extremely high specific capacitance of 2133.3 F/g at a current density of 4 A g-1. FE-SEM results showed that...
Study of Effective Parameters on Roasting of Zinc Sulphide in a Fluidized Bed Reactor
, M.Sc. Thesis Sharif University of Technology ; Halali, Mohammad (Supervisor)
Abstract
In this study, four parameters were investigated including temperature, inlet flow rate, gas composition (oxygen) and particle size on the roasting of Bama company zinc sulfide concentrate in Fluidized bed reactor. Initially, primary sample was heated in electric furnace at 125℃ for 24 hours until the moisture content dried. Then roasting operation was done at 700 and 900℃. The operation was carried out on three range of particle size including 300-500, 500-700 and 700-1000 microns and flow rate was greater than the minimum flow rate of Fluencing. To investigate the effect of flow rate and gas composition input, 500-700 micron particle size range was selected. The effect of 155, 172 and 188...
Surface Passivation of PbS Colloidal Quantum Dots for Photovoltaic Applications
, Ph.D. Dissertation Sharif University of Technology ; Simchi, Abdolreza (Supervisor) ; Ashuri, Hossein (Supervisor)
Abstract
Solution-processed quantum dots (QDs) have attracted significant attention for the low-cost fabrication of optoelectronic devices. Here, we synthesized PbS QDs via hot injection method and passivated the trap states by using short thiols and dopant elements for photovoltaic application. In order to study the effect of dopants on photovoltaic application, PbS QDs were doped by using three different cations: Cadmium, Calcium, and Zinc. The results showed that Cd dopant has a better improvement than Ca and Zn dopants in order to increase the efficiency of the PbS QDs solar cells. We achieved solar power conversion efficiencies of 5.81% using Cd therapy. Recently, hybrid nanocomposites...
Deposition of CdS on Nanostructured and Mesoporous TiO2 Film for Solar Cell Application
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
In this project, The cadmium sulfide nanoparticles were formed on a nanostructured and meso-porous titanium dioxide layer and its properties were characterized. Deposition process of titanium dioxide and cadmium sulfide has been performed respectively in one stage and two stages of dipcoating. In order to probing effects of temperature and dipcoating time, samples have been prepared in various times and temperatures. Also, some of the samples have been annealed. Thickness of titanium dioxide and cadmium sulfide coatings were approximately measured 1 μm and between 3-5 μm, respectively. As expected, XRD results disclosed that cadmium sulfide and titanium dioxide were formed in the form of...
Development of Ratiometric Sensors Based on Fluorescent Nanostructures for Naked Eye Detection
, Ph.D. Dissertation Sharif University of Technology ; Hormozi-Nezhad, Mohammad Reza (Supervisor)
Abstract
In the first part of this research, we have developed a simple and effective ratiometric fluorescence sensor for selective detection of dopamine (DA) in alkaline media by simply mixing thioglycolic acid (TGA) functionalized orange fluorescent cadmium telluride (CdTe) quantum dots (QDs) with amino-functionalized blue fluorescent carbon nanodots (CDs). Under a single excitation wavelength of 365 nm, the sensor exhibits dual-emissions centered at 445 and 603 nm. The fluorescence of CdTe QDs is selectively quenched by DA, whereas the fluorescence of CDs is insensitive to the analyte. In the presence of different amounts of DA, the variations in the dual emission intensity ratios exhibit a...
Safety Assessment for H2S Releasing in Arak Heavy Water Factory (GS(03) Plant) Using Probabilistic Safety Assessment Method (PSA)
, M.Sc. Thesis Sharif University of Technology ; Ghofrani, Mohammad Bagher (Supervisor)
Abstract
In general, release of hazardous gas in chemical process plants could be due to two reasons. First is failures due to degradation of components that have inventory of hazardous gas in standard process conditions, and the second is deviation of system from standard process conditions because of different failure modes of related components, e.g. controller equipments. The purpose of this study is, calculating the probability of H2S releasing in GS(03) plant of Arak Heavy Water factory, using PSA methods and its risk assessment. At First, fifteen groups of initiating events were identified with Hazop study for desired system. Then, for calculating the frequency of each event, the combination...
CdS:Mn and CdS:O Nanoparticles Growth via Thermochemical and Microwave Methods and Studding the Photoluminescence Properties
, M.Sc. Thesis Sharif University of Technology ; Taghavinia, Nima (Supervisor)
Abstract
The optimization of CdS photoluminescence nanoparticles which has been considered as one of the most important II-VI semiconductors has been studied here. As the first step, synthesis parameters effect on CdS:Mn photoluminescence intensity has been regarded by thermochemical method. Effect of parameters like pH solution, heating time and capping agent concentration on photoluminescence of these materials has been experimented. What seemed so important was reaching nanoparticles with suitable nano size and nano structure and having highly photoluminescence intensity. Observing the good effect of Oxygen on photoluminescence of CdS nanoparticles leaded us to concentrate on synthesizing CdS:O...
Preparation and Characterization of Nanocrystalline One-dimensional Cadmium Sulfides by Solvothermal Process for Solar Cell Application
, M.Sc. Thesis Sharif University of Technology ; Mohammadi, Mohammad Reza (Supervisor)
Abstract
One-dimensional (1D) cadmium sulfide (CdS), nanostructures have significant potential applications in solar cells, photocatalysts and many electronic devices. There are many experimental approaches to synthesis 1D CdS nanostructures. Among them solvothermal method has many advantage such as controllable and inexpensive method. 1D CdS nanostructures with different properties in morphology, crystal structure, band gap energy and etc can be obtained by controlling solvothermal processing parameters. In the present work the effect of solvothermal processing parameters including reaction temperature (120ºC ,160ºC and 200ºC), process time (12h, 48h and 72h), sulfur source (S powder, Thiourea and...
Modeling for Sensing Behavior of SnO2-CuO Nanostructures toward H2S Gas
, Ph.D. Dissertation Sharif University of Technology ; Ghorbani, Mohammad (Supervisor) ; Moosavi, Ali (Supervisor) ; Mohammadpour, Raheleh (Supervisor)
Abstract
H2S is a toxic and corrosive gas which is detrimental for both human’s health and some of important industries such as oil and gas. Based on different experimental research among various systems, resistive sensors fabricated from SnO2-CuO nanostructures have promising performance toward detection of this gas. High sensitivity and selectivity, response time of order of seconds, recovery times of order of tens of seconds and determining concentration of H2S gas below ppm level are advantages of this system. Unfortunately due to lack of a theoretical model, current experimental researches are excessively based on “trial and error” methodology. In this research some of the basic questions which...
Synthesis, Characterization and Catalytic Activity of Supported Vanadium Schiff Base Complex as a Magnetically Recoverable Nanocatalyst in Epoxidation of Alkenes and Oxidation Of Sulfides
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this project, a new magnetically recoverable nanocatalyst was developed by immobilizing of vanadyl acetylacetonate, [VO(acac)2], onto surface of silica coated magnetite nanoparticlest that modified by reaction between 3-aminopropylthriethoxy silane and 5-bromosalicylaldehyde. In the first step, magnetite cores were synthesized by co-precipitation method and coated by tetraethyl orthosilicate (TEOS) and modified by 3-aminopropyltriethoxy silane to provide a precursor for Schiff base condensation reaction. In the next step, amino-functionalized silica coated magnetite nanoparticles were reacted by 5-bromosalicylaldehyde to formation a Schiff base moiety onto surface of magnetite coated...
Immobilazation of Manganese-Porphyrin Complex on Magnetic Nanoparticles and its Application as a Catalyst for the Epoxidation of Olefins and Oxidation of Sulfides
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
The goal of this study is to synthesise and study the catalytic properties of a Mn-Porphyrin complex fixed on a magnetic nanoparticle bed. This nanocatalyst was used in oxidation of sulfides and epoxylation of olefin. In the multistage synthesis of this catalyst, iron oxide magnetic nanoparticles were first prepared, then, by silanizing these nanoparticles, and then using the 3-chloropropyltrimethoxy methanol reactor, Immobilzation the material on the substrate and immediately react in reaction Substitution of the nucleus of friendship and using a sodium azide reaction, bromide is replaced by azide. Subsequently, by synthesising 4-hydroxy porphyrin and replacing one of its positions with...
Immobilized Manganese-porphyrin and Molybdenum-Schiff Base Complexes on Functionalized Magnetic Nanoparticles as Efficient Recyclable Nanocatalysts in Hydrocarbon and Sulfide Oxidation Reactions
, Ph.D. Dissertation Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this thesis, functionalized Fe3O4 nanoparticles have been utilized as a support for immobilization of homogeneous catalysts. The catalytic activity of the supported heterogeneous nanocatalysts was investigated in hydrocarbon and sulfide oxidation reactions. In the first part of this research, imidazole functionalized Fe3O4 nanoparticles (Fe3O4@SiO2-Im) were used as a support to anchor manganese porphyrin complex, [MnT(4-OMeP)P]OAc; via axial ligation. Catalytic application of the immobilized manganese porphyrin was studied in oxidation of alkenes and sulfides. To find suitable reaction conditions, the effect of different parameters such as solvent and temperature on immobilization process...
Synthesis and Characterization of Tungsten (VI)Complex with Oxazine Ligand and its Catalytic Application in Oxidation of Sulfides to Sulfoxides
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this study a novel oxo-diperoxo tungsten(VI) complex [WO(O2)2(phox)] was prepared by reaction of WO3 in H2O2 with oxazine-type ligand, 2-(2′-hydroxyphenyl)-5,6-dihydro-1,3-oxazine (Hphox). The complex was characterized by FTIR, 1H NMR and elemental analysis. The single-crystal X-ray diffraction studies revealed a seven coordinate tungsten center with a distorted octahedral geometry. The [WO(O2)2(phox)] complex was applied as a catalyst in efficient, and selective oxidation of sulfide to sulfoxide using 30% H2O2 or UHP as oxidants. This catalyst showed excellent catalytic activities and high selectivities in producing a variety of aryl and alkyl sulfoxides under mild conditions. To get...
Synthesis, Characterization and Modeling of Active Sites in Dinuclear Metalloenzymes
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
In order to have more understanding of the cooperative effect between the metal centers in the multimetallic complexes, on their physicochemical properties and chemical reactivity, some new bi- and tetra-nuclear Cu(II), Ni(II) and Pd(II) complexes of compartmental binucleating ligands were synthesized and characterized. In this study, a series of new compartmental binucleating thiophenol-based proligands PL1-PL4 from the Schiff base condensation of 2 equiv. of o-aminophenol or 2-amino-4-methylphenol with 1 equiv. of 2,6-diformyl-4-alkyl- thiocarbamoyl were synthesized and characterized. New Bi- and tetra-nuclear copper (II) complexes derived from these binucleating compartmental...