Sharif Digital Repository

Most of industrial and laboratory processes are faced with liquid-liquid emulsions particularly aqueous-organic ones in their different product streams which determine the need to perform phase separation due to enviromental problems or need to increase the product purity. In this project, due to presence of a water-hexane two phase flow mixture in the outflow of a microractor that performs Lithium-Bromine exchange reaction, a capillary microchip separator has been designed in order to separate water through capillary channel and hexane through main channel outlet using interfacial forces and wettability effects. To obtain a desired phase separation, the pressure drop through main channel... 

The main purpose of this project is synthesis of the silica nano-sheets by means of microfluidic techniques. Continuous process, precise control of reaction condition, and higher production rate can be considered as main pros of silica nano-sheets synthesized by microfluidic platforms. General method can be explain as follow: first two oleic and aqueous phase are injected to the microfluidic system, then oleic phase breaks down in aqueous phase drop-wisely and by performing sol-gel reaction on the oil-water interface a silica crust is made on oil droplets. Eventually, oil droplets are left the system and broken down and silica nano-sheets are made. FESEM and microscopic images of... 

There are different sulfur compounds in the crude oil, and after combustion all of these sulfuric compounds produce sulfur dioxide, this sulfur dioxide cause acid rain, deactivation of catalysts and also environmental bad effects. So the amount of sulfur that is released should be controlled and this is done by removing sulfuric compounds before combustion. zeolites as adsorbent of sulfuric compounds has been used widely by researches and had given good results. molecular dynamics simulation as an effective way for describing the behavior of these compounds in the molecular level and in scales of angstrom has been used and the effect of van der waals and electrostatic forces between sorbates... 

Consumption of oil and gas as energy carrier leads to irreversible environmental effects related to greenhouse gases emission. Hence, for the reduction in greenhouse gas emission, a shift to renewable resources for energy supply is recommended. However, in recent years, hydrogen has emerged as the most promising clean energy carrier for generating electrical power through fuel cells. Nevertheless, production of renewable hydrogen is the main barrier to the development of hydrogen as an energy carrier. Aqueous phase reforming of oxygenated hydrocarbon is developed by Dumesic for producing renewable hydrogen-rich gas with low CO. Since it is expected that, use of new technology such as the... 

Today, microreactors come into focus due to their exclusive characteristics including high surface-to-volume, lower consumption of reagents and fast mixing. In this study, optimization of the Br-Li exchange reaction as a consecutive reaction using glass microreactor is investigated. To construct glass microreactor, laser ablation and thermal bonding method are utilized. In order to find the best yield and selectivity of the reaction, various parameters, such as solvent, equivalent ration of the two reagents, concentration of the reagents, residence time and flow rates of the reagents are examined. In addition, atomic force microscopy (AFM) analysis was used to determine the surface... 

Microfluidic is a science and technology in which they study the behavior of fluids, control them and design devices or systems with dimensions of tens to hundreds of micrometers. The technology has the ability to design and manufacture macro-scale and micro-scale equipment, such as micro-pumps, micro-valves, micro-filters, micro-mixers, micro-reactors, and other equipment. The benefits of this technology include the use of low sample size, low waste of energy, low power consumption, short response time, high system performance, portability and performance of several operating phases in a compressed piece such as production, isolation and analysis. Also, the very low amount of chemicals and... 

In this research incorporation of SAPO-34 zeolite filler into polycarbonate membrane was investigated for fabrication of mixed matrix membrane (MMM). The main purpose of addition of zeolite in polymer matrix is to enhance the separation properties of pure membrane by means of the selective pores of SAPO-34. SAPO-34 possesses pores with proper size for separation of CO2 from CH4 by molecular sieving mechanism. Pure polycarbonate membrane and PC/SAPO-34 MMM was prepared by solvent evaporation method using dichloromethane as solvent. Zeolite loading was varied between 5-30%wt. First of all, polycarbonate was characterized by DSC, FTIR and viscometer analysis in order to determine all the... 

The properties of 3 nm-diameter fluorinated silica nanoparticles with different coverage percent of CF3 groups as water and oil repellents were investigated at the water-rock and decane-rock interface using molecular dynamics simulation. Simulating a pore of rock in presence of water and decane molecules separately, resulted in liquid bridging for both of liquids. The density profiles of liquids in the pore clearly show several highly ordered layers packing of the molecules close to the rock surface. Distribution of liquid molecules around the nanoparticles is much influenced with increasing CF3 groups on the nanoparticle surface. Results show that adsorption of functionalized silica... 

The purpose of this research is the synthesis of nanoparticles using micro fluid glass.The microfluidic glassy building is studied. Glass microfluidic microchannels making hydrophobic the continuing experiments carried out so that the water droplets in the organic phase and at the end of nanoparticles should be synthesized. Tests hydrophobic microchannels and water droplets in the organic phase was formed. In order to ensure an escape water contact angle and FTIR micro-channel test is taken and to avoid the droplets merged with each of surfactant SDS was used. In the end, DLS and FESEM nanoparticles synthesized using the tests have been evaluated and the concentrations of reactants and flow... 

By applying the Pinch Technology and Exergoeconomic simultaneously, to a complex process system, beneficial and energy-efficient measures are identified.In the present research “Three-link-model” Exergoeconomic methodology optimizes the system and contrary to traditional exergoeconomic methods, reversed method is used. The approach proposed for optimization of such a complex system is to iteratively optimize subsystems. Since assumptions considered by conventional Exergoeconomic for calculating the cost-optimal exergetic efficiency and relative cost difference, are not applicable, new assumptions are to be considered. Unlike traditional Exergoeconomic method, product’s exergetic specific...