Sharif Digital Repository

Nowadays, different processes are designed in order to convert raw materials to value added products. One of these is the Bentonite sulfur production process. The most important equipment in this process are stirred tanks where mixing operation of molten sulfur with some additives such as functionalized Bentonite and oxides of iron, zinc and manganese are performed.
In this thesis, following the design and making of a laboratory scale glass baffled stirred tank, the viscosity of molten sulfur and additive suspension has been measured at different temperature (125, 130 and 135oC) and several formulations. Concentration profile of Bentonite has also been obtained by means of local sampling... 

In recent years, the reductive dehalogenation of the chlorinated hydrocarbons using nanoscale zerovalent iron (nZVI) represents a promising approach for underground remediation. Regarding commercialization of this technique, instability and unknown nature of nZVI particle are still challenging tasks that should be considered.
In the current work, Nanoscale zero-valent iron (nZVI) and palladized iron (Pd/Fe) bimetallic particles were synthesized and employed to react with chlorinated compound (PCE) in water to investigate its degradation behaviors. The results show that the reactant ratio, stabilizer amount and temperature are the main parameters with the considerable effect on PCE... 

The Visbreaking process is one of the Residue upgrading method, which, in addition to the production of mid-distillate products, also reduces the viscosity of feed. By reducing the viscosity of the feed, the amount of cutter stock is reduced to produce fuel oil. Since the refiners want to achieve the maximum conversion in the visbreaker unit, it is necessary to estimate the proper operating conditions and distribution of the products. Increasing in conversion in a visbreaker unit will lead to a refinancing profit. In this work, four Vacuum Residual oil from Iranian Refineries were selected for studying on visbreaking process. Experiments were carried out at RIPI-Petroleum Refining Technology... 

High-capacity electrode materials are crucial for enhancing the performance of supercapacitors. Transition metal sulfides are considered promising materials for supercapacitor applications due to their high theoretical capacity and good electrical conductivity. Additionally, cerium oxide improves the performance of supercapacitors due to stable reversible oxidation states and greatly supported the faradaic redox reaction. In this study, ceria nanosheets incorporated with MCoS (M=Mn, Zn, Cu) were synthesized successfully through a facile hydrothermal method by sulfidation of MCo LDH/CeO2. The structural and morphological characteristics were analyzed using X-ray diffraction, scanning electron... 

In this advanced research, titanium dioxide nanotubes were initially synthesized using the hydrothermal method. Subsequently, they were coated with polyaniline, polyindole, or a combination of both polymers using oxidative polymerization. The application of these composites for the removal of the organic pollutant 4-nitrophenol in wastewater was investigated under visible light irradiation from a 250-watt sodium lamp and in the presence of hydrogen peroxide as an oxidizing agent. To characterize the synthesized photocatalysts, various tests were conducted, including X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS),... 

The conventional approach to investigate the reservoir performance is to build a detailed geological model, upscale it, and finally run flow simulation which is computationally very expensive. In addition, during the early stage of life of a reservoir, due to the lake of certain data, this method is usually based on analogues or rules of thumb and not detailed reservoir modelling. Therefore, there is a great incentive to produce much simpler physically-based methodologies. The main focus of this thesis is to use percolation approach to estimate the uncertainty in the reservoir properties. This method considers a hypothesis that the reservoir can be split into either permeable (i.e....