Sharif Digital Repository

In this project, theoretical and experimental study of methane adsorption on Multiwall Carbon Nano-Tubes (MWCNT) has been performed. This study has been conducted in the way to achieve a suitable method for methane storage and transportation. To carry out the experiments, the volumetric method was used up to 500 psia at various temperatures of 298.15 K, 303.15 K, 308.15 K. The effect of moisture was also studied at 298.15 K. Also, various adsorption isotherms were used to model the experimental data collected in this work. The results showed that the amount of methane adsorbed on the MWCNT can decrease with increasing the moisture and temperature of the adsorption cell. In order to... 

Supported Ionic Liquid Membranes (SILMs) are fabricated by saturating the pores of a porous support with ionic liquids. To assess the performance of SILMS, it is necessary to obtain data about the properties of ionic liquids such as diffusivity, solubility, and etc. To accomplish this task, in this project the permeability and diffusivity of CO2 and CH4 through three immidazolium-based ionic liquids: [bmim][PF6], [hmim][Tf2N], and "1-methyl-3-(3- tri methoxi silil propyl) imidazolium bis (tri fluoro methyl solphonyl)" , in the temperature range between 27-45 ℃ and pressures within 10-50 kPa, are measured. It is shown in data validation section that the results of this study are in good... 

In the current situation of energy, gas storage is one of the basic needs. Different methods have been used in order to storage gases. One of these methods is the adsorption of gases on solid materials, which are called as adsorbents. In recent decades, different gas adsorbents, such as silica gel, zeolite and activated carbon, have been studied. Most of these adsorbents are nonorganic materials. Recently, many researchers have tried to apply polymeric materials as gas adsorbents. In this regard, the obtained results on the different polymers showed that it is possible to achieve the proper gas adsorption. In this study, different samples were prepared from polysulfone by phase inversion... 

Direct injection spark ignition lean burn engine with stratified mixture is concerned recently and research and development are in its initial stage. In this thesis, at first a thermodynamic simulation of these engines was done for investigating of stratified mixture effects on combustion characterization and compare it with homogeneous one. In this modeling we use from turbulent flame speed model for mass burning rate analysis, multizone model for exact measuring of temperature distribution, full chemical kinetic model for emission concentrations and some proposed mixture formation for predicting of stratified mixture. The results shown that stratification is caused to improve combustion... 

Trash production in Iran is increasing. The majority of trash is being buried and that induces the emission of methane gas (CH4), which is a greenhouse gas. In this thesis, the aim was mostly to remove methane from greenhouse gases by applying several cheap and abundant substances. For this purpose, a biofilteration system was provided. It has been tested using two packings: straw and plastic. To provide the necessary materials for bacterium growth, a nutrient solution was used. The results of this work have revealed that plastic proved to be more effective than another substance and the removal percent obtained was about 61%. The result for straw was 42%. Furthermore, the experiments were... 

Environmental pollution and depleting the resources of energy are two significant crises which has been caused by excessive Energy consumption in all over the world. One of the most appropriate and reproducible energies is the Biogas energy. Huge amount of sewages and dry wastes are produced in cities every day can causes devastated damages to environment. All types organic matter extracted from different processes of treating sewages are influenced by germ activities and will be transformed to mineral structures and the final product of these reactions would be gases which can be used as enormous sources of fuel and energy. There are different devices made all over the world to be utilized... 

Mixed matrix membranes (MMMs) are new generation of membranes which possess simple processability of polymeric membranes and high separation ability of zeolitic membranes. The present study, concentrates on the fabrication of MMM for CO2/CH4 separation in a combined method as encompasses not only higher permeability but also superior selectivity in comparison with conventional polymeric membranes. The most appropriate technique for MMM making, is the process which provides participation of distributed zeolite particles in separation efficiently while the polymeric matrix acts just like a particle support and dose not play an effective role in separation. Investigations demonstrates that... 

Influence of attachment of Multi Walled Carbon Nanotubes (MWCNT) on various nickel nanocatalysts produced by the electroless plating method was investigated via Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive Spectroscopy (EDS), Atomic Absorption Spectroscopy (AAS), X-ray Diffraction (XRD), Brunauer-Emmett-Teller (BET) measurements, Temperature Programmed Reduction (TPR) and Temperature Programmed Oxidation (TPO) tests. Application of TPR/TPO data to Kissinger (Redhead) Equation yielded the activation energies of both nickel reduction and nickel oxidation reactions. Addition of MWCNT improved the catalytic effects by easing of... 

The main aim of this project is to develop a model for risk assessment of energy service companies (ESCO) using energy efficiency and emission trading markets. For this purpose, structure of the market has been developed and then by explaining the interactions between ESCO and other members of the market, ESCO's cash flows have been determineded. In the next stage, probability distribution of the cash flows have been extracted and risk assessment have been performed. The differences in energy prices coming from subsidies is the foundation of this market. In this market, ESCO will sell the saved energy rights which has been achieved in the low price level sector to the other sector with high... 

The conversion of CO2 gas into value-add chemicals known as solar fuel technology attracted much consideration from the beginning of the 21st century owing to the potential of this technology in solving the climate change and energy shortage issues. In the present study, a well-known photocatalyst, TiO2, was doped with Bismuth element and was subjected to Pt nanoparticles loading as a cocatalyst to boost the photocatalytic CO2 conversion. Pristine TiO2 and Bi-doped samples were prepared by sol gel method. Then, a facile photo-deposition method was employed to introduce Pt onto the surface of TiO2. Various characterization techniques including XRD, DRS, BET, PL, FTIR, FESEM and TEM, were used... 

Pre-reduction of some manganese sources (low-grade Venrach and Godar-Sabz ores, high-grade Comilog ore, pellet, pure oxide) by methane gas has been investigated in this research. HSC-Chemistry and FactSage software were used for thermodynamic study of the process. Thermodynamic results indicated that methane may progress to manganese carbide formation, and the reduction process can run autonomously involving less carbon dioxide emission comparing to common ferromanganese process. Several techniques including XRF, XRD, in-situ XRD, SEM-EDS, and thermogravimetry were used in sample characterization and experiments. In addition to the thermal decomposition reactions which were affected by... 

Dry reforming methane is a process during which two greenhouse gases, CH4 and CO2, using Ni-based catalysts, are altered into valuable H2 and CO gases, which are very useful from an economic and environmental point of view. The main problem with Ni-based catalysts is the formation of carbon in the dry methane reforming, which leads to rapid deactivation of the catalyst. In this research, a 10Ni-5Co/Al2O3 bimetallic catalyst was prepared by one-pot microwave-assisted combustion synthesis with a stoichiometric amount of fuel (urea) and without the use of additives. The catalyst was then calcined for 12 h at 550oC. The structure, chemical composition, particle distribution, and morphology of...