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    Bromo-lithium Exchange Reaction in Organic Synthesis and Continuous Separation of Organic and Aqueous phase Reactions by Microfloid Technique

    , M.Sc. Thesis Sharif University of Technology Pourasghar Mohammadi, Ali (Author) ; Mohammadi, Ali Asghar (Supervisor) ; Bastani, Dariush (Supervisor)
    Today, with the development of micro-technology in chemical reactions, the use of appropriate systems for the separation and purification of synthesized chemicals seems to be necessary. In this study, the continuous synthesis of bromide-lithium exchange reaction and the separation of organic and aqueous phase products in micro systems was investigated.The method used to construct micro-separator and micro reactor, a laser engraving technique, and thermal bonding of glass to glass.In the first step, the factors affecting the separation of organic and aqueous phase in the capillary micro-separator, such as the width of the capillary, the length of the capillary, the number of capillaries and... 

    Fabrication and Evaluation of Catalytic Microreactors to Verify the Conversion of Ethyl Mercaptan

    , M.Sc. Thesis Sharif University of Technology Karami Basiri, Mohammad (Author) ; Kazemeini, Mohammad (Supervisor)
    Sulfur compounds are largely an impurity in fossil fuels such as natural gas, crude oil and coal. In natural gas, the main sulfur compounds are hydrogen sulfide (H2S), carbonyl sulfide (COS),and C1-C3 mercaptans.Commercial methods for removing these compounds require the introduction of additional reactive substances (O2, H2, Olefins, NaOH, etc.), which often results in the production of other pollutants. Microfluid is a branch of science and technology that involves studying the behavior of fluid, the use of fluid and the manufacture of equipment or systems that are carried out in micro-channels.The dimensions of these canals are about ten to several hundred micrometers, and high of... 

    Reaction Modeling of Mercaptan Conversion to H2S and Hydrocarbons over ZSM-5 Catalysts in Microreactor

    , M.Sc. Thesis Sharif University of Technology Ayatizadeh Tanha, Maryam (Author) ; Kazemeini, Mohammad (Supervisor)
    Microfluidic devices carry fluids in channels with the diameter in the scale of micrometers. Low consumption of raw materials, higher selectivity, enhancement of heat and mass transfer, and improved safety considerations are benefits of the application of microfluidic devices. In this venue, catalytic microreactors get high potential in the filed of the catalytic reaction. In recent years due to strict international environmental regulations, the sulfur content in fossil fuels should be at the minimum content. MEROX process is to most common route to remove mercaptan from the LPG dreams in the material gas refineries. However, in this process, the production of DiSulfid Oil (DSO) is a... 

    Bromine-lithium Exchange Reaction in Organic Synthesis Using Glass Microreactor

    , M.Sc. Thesis Sharif University of Technology Zeibi Shirejini, Saeed Reza (Author) ; Mohammadi, Aliasghar (Supervisor)
    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... 

    Mass Transport Analysis of Non-Newtonian Fluids under Combined Electroosmotically and Pressure Driven Flow in Rectangular Microreactors

    , M.Sc. Thesis Sharif University of Technology Yousefian, Zakie (Author) ; Saidi, Mohammad Hassan (Supervisor)
    In recent two decades, with developments in micro and nano scale fabricating techniques, use of microfluidic systems is increasing in different fields. How to drive fluid is a hard question because of high pressure drop in micro scale. Different methods has been suggested to solve this problem, among which, electroosmotic pump is preferred because of its advantages. One of the main applications of microsystems is in biomechanical devices like microreactors which are usually working with non-Newtonian fluids. The cross section of these devices are most often close to rectangular shape.Therefor, in this study,Hydrodynamic charactristics and mass transport of non-Newtonian fluids under... 

    An Investigation to the Effect of Heterogeneity of Surface’s Potential on Mass Transport and Surface Reaction Kinetics in Microreactors

    , M.Sc. Thesis Sharif University of Technology Abodllahzadeh, Mojtaba (Author) ; Saeedi, Mohammad Saeed (Supervisor)
    Nowadays, technology has facilitate the miniaturization of laboratory systems, medical and drug delivery tools. As a result, researchers are interested to miniaturize these tools. The extensive research in this field led to invention of lab-on-a-chips, which with the size of a few µm to a few mm, can do multiple tasks in human body. One of most important components of these devices, is microreactor. A wide range of measurements and reactions in microreactors, need to bind with the receptors at the surface of the cylindrical microchannels. For this purpose, this study, investigates the effects of surface heterogeneity on microreactors performance. In this Thesis, the governing equations were... 

    Nanoparticle Synthesis Using Droplet-based Microfluidics

    , M.Sc. Thesis Sharif University of Technology Ghasemi, Mohammad Javad (Author) ; Mohammadi , Aliasghar (Supervisor) ; Molaei Dehkordi, Asghar (Co-Advisor)
    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... 

    Aqueous Phase Reforming of Biomass Using Micro-reactor

    , M.Sc. Thesis Sharif University of Technology Entezary, Behzad (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Aliasghar (Supervisor)
    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... 

    Production of Vegetable Oil Biodiesel by Heterogeneous Catalytic Trans-Esterification Method in Micro-Reactor

    , M.Sc. Thesis Sharif University of Technology Piran, Samira (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Ali Asghar (Supervisor)
    The purpose of this study is to study heterogeneous nanocatalysts for the production of biofuels by the method of exchange of styrene using oil and methanol as a fossil fuel alternative. Preparation of nanocatalysts, performing characteristic tests and investigating the reaction in different operating conditions in the batch reactor has already been studied. Therefore, in this study, the production of biodiesel fuel using the trans-esterification of canola oil with nanocatalysts in the micro-reactor reactor will be discussed. Previously, a heterogeneous catalyst (lithium based on calcium-lanthanum) was constructed using a co-incineration method and a wet inoculum, and as active and stable... 

    Optimization and Continuous Synthesis of Artemisinin Using Core-Shell Nano-Catalysts by Means of Micro-Rector

    , Ph.D. Dissertation Sharif University of Technology Tamtaji, Mohsen (Author) ; Kazemeini, Mohammad (Supervisor)
    Artemisinin as a natural peroxide possess a high anti parasite, and antivirus (Covid-19) properties which could be synthesized through the photooxygenation of dihydroartemisinic acid. This production possesses a lot of difficulties, for example, homogeneous catalyst is used for the photooxygenation reaction which makes photocatalyst and solvent non-reusable. In addition, separation of products from solvent and photocatalysts is difficult. Photooxygenation needs high pressure and low temperature which is very costly. Besides, because of several by-products which are producing during photooxygenation and protonation reactions, Artemisinin yield decreases. The aim of this study is to optimize... 

    Microreactor Synthesis of Medicine by Catalyzed Coupling Reaction

    , M.Sc. Thesis Sharif University of Technology Hashemnezhad, Emad (Author) ; Kazemeini, Mohammad (Supervisor) ; Hosseinpour, Vahid (Co-Supervisor)
    Idiopathic pulmonary fibrosis is the most common type of pulmonary fibrosis that causes ulcers inside the lungs. In addition to Nintedanib, Pirfenidone is currently the only compound approved by the US Food and Drug Administration in 2014 for the treatment of idiopathic pulmonary fibrosis. Meanwhile, in the pharmaceutical industry, drug synthesis is usually done through batch-wise processes, and pirfenidone is currently only produced through batch-wise processes. Hence, this study aims to change the synthesis method of this drug, which is traditionally performed through batch-wise processes, to a continuous flow process. Therefore, a micro-reactor technology can be adopted which offers a... 

    Synthesis of Silica Nanosheets Using Droplet-based Microfluidics

    , M.Sc. Thesis Sharif University of Technology Tamtaji, Mohsen (Author) ; Mohammadi, Aliasghar (Supervisor)
    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... 

    Economically Optimal and Inherently Safe Design and Operation of Microreactor for Hydrogen Production in Portable Power Generation Devices Such as PEM Fuel Cell

    , M.Sc. Thesis Sharif University of Technology Ghodba, Ali (Author) ; Rashtchian, Davood (Supervisor) ; Sharifzadeh, Mehdi (Supervisor)
    Due to high efficiency and modular production ability of fuel cells, they have been used extensively in the power plants, especially in portable devices such as fuel cell vehicles. The commercialization of the equipment is dependent on ensuring the safety of their operations. Many of these platforms employ steam reforming reactions at very high temperature in order to produce the hydrogen, which is implemented as the fuel in the PEM fuel cell. The technique of miniaturization is a promising approach to design a chemical process in which the rate of transport phenomena such as the mass and heat transfer are intensified by reducing the size of the reactor and allowing the process to be run... 

    Production of Lactic Acid from Glycerol in Microchannel Reactors in the Presence of Copper-Based Catalysts

    , M.Sc. Thesis Sharif University of Technology Jalal Sahandi, Pooya (Author) ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samaheh (Supervisor)
    Hand in hand with the flourish of the biodiesel industries, glycerol has turned into an abundant waste chemical posing obstacles to their large-scale implementation. Devising measures for efficient transformation of glycerol into value added products is a promising alternative to its large-scale disposal into the nature that would also increase the competitiveness of biodiesel fuels. In this study, production of lactic acid (LA) as a valuable chemical with wide applicability is studied in a continuous process with glycerol as a cheap and convenient feedstock. In this regard, the state-of-the-art approaches in catalytic conversion of glycerol to LA are reviewed. A catalytic method using... 

    Micro-Channel Fabrication and Evaluation to Remove Mercaptan from Gas Streams

    , Ph.D. Dissertation Sharif University of Technology Hosseinpour, Vahid (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Ali Asghar (Supervisor) ; Rashidi, Alimorad (Supervisor)
    Due to the potential risk of sulfur compounds in fossil fuels and according to today’s regulations, sulfur content should be kept as low as possible, e.g., below 5 ppm. Mercaptans are one of the sulfur components in natural gas. Scope of this research defined as catalytic removal of ethyl mercaptan from the gas stream. For this purpose, two microreactor systems placed in series. In the first microreactor, catalytic decomposition of ethyl mercaptan has been investigated. In the first step of this survey, a microreactor with 24 microchannels with a newly designed distributor has been developed with a computational fluid dynamic technique. in comparison to the conventional triangular... 

    Continuous Synthesis of Medicine Utilizing Catalyst Through a Microreactor System

    , M.Sc. Thesis Sharif University of Technology Erfani Gahrooei, Amir Reza (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor) ; Hosseinpour, Vahid (Co-Supervisor)
    Nowadays, the use of microreactors is receiving a great deal of attention due to the unique characteristics of such systems, such as high surface-to-volume ratio, low material loss, greater safety, and minimizing mass and heat transfer limitations. In this study, the optimization of the continuous-flow synthesis of Plavix by Cu-MOF heterogeneous catalyst utilizing a glass microreactor was investigated. Structural characteristics of the catalyst were investigated using X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and BET surface area studies to describe the structure and morphology of the catalyst. In order to build... 

    Continuous Catalytic Synthesis of Medicine Through a Micro-Reactor System

    , M.Sc. Thesis Sharif University of Technology Jahangirifard, Shayan (Author) ; Kazemeini, Mohammad (Supervisor) ; Hosseinpour, Vahid (Co-Supervisor)
    In the past decades, the production of various active pharmaceutical ingredients in batch processes was common. But today, the approach of pharmaceutical companies has changed and the use of the equipment and continuous processes such as microreactors has become common for reasons of safety, better mass and heat transfer, reduction of operators, and ease of scale-up. Unlike many top-selling drugs such as Ibuprofen and Artemisinin, Clopidogrel, the world's third best-selling drug needed by cardiac patients, has been manufactured only in batch processes. Due to the increase in the average age of the population, the urgent need for the use of Plavix (clopidogrel) has increased in recent years.... 

    CFD-Assisted Design of Microreactor and Evaluation for Continuous Drug Synthesis

    , M.Sc. Thesis Sharif University of Technology Varposhti, Daniel (Author) ; Kazemeini, Mohammad (Supervisor) ; Hosseinpour, Vahid (Co-Supervisor)
    Manufacturing in many industries, such as electronics, petrochemical, automotive, and food, has long relied on continuous approaches, while the pharmaceutical industry has traditionally been processed in batch reactors. Since the beginning of the third millennium, continuous drug synthesis has received attention due to its multiple advantages over batch systems, which include process safety, adaptability, controllability, economic efficiency, scale-up, and enhancing performance. In this project, the pharmaceutical intermediate 1,4-benzodiazepine, which is usable as a precursor of diazepam and flurazepam, is continuously synthesized in a 400 microliters integrated micromixer and microreactor... 

    3D modeling of reaction-diffusion dynamics in an electrokinetic Y-shaped microreactor

    , Article Sensors and Actuators, B: Chemical ; Volume 235 , 2016 , Pages 343-355 ; 09254005 (ISSN) Helisaz, H ; Saidi, M. H ; Sadeghi, A ; Sharif University of Technology
    Elsevier  2016
    We perform a 3D numerical modeling of reaction-diffusion dynamics in a Y-shaped microreactor, considering a fully developed combined electroosmotic and pressure-driven flow. The governing equations, based on a second-order irreversible reaction, are solved invoking a finite-volume approach for a non-uniform grid system. We demonstrate that the reaction is highly position dependent: more production is observed adjacent to the horizontal walls for a favorable pressure gradient, whereas both the wall and centerline are the regions of highest production when a back pressure is applied. We further show that, to achieve the maximum production rate, the EDL should be thick enough, the pressure... 

    Simulation of continuous catalytic conversion of glycerol into lactic acid in a microreactor system: A CFD study

    , Article Journal of Industrial and Engineering Chemistry ; Volume 104 , 2021 , Pages 258-271 ; 1226086X (ISSN) Jalal Sahandi, P ; Kazemeini, M ; Sadjadi, S ; Sharif University of Technology
    Korean Society of Industrial Engineering Chemistry  2021
    Hand in hand with the flourish of the biodiesel industry, glycerol (GLY) as an inconvenient by-product has generated environmental and sustainability concerns. Devising measures for efficient transformation of GLY into value-added products is a promising solution. In this contribution, the transformation of GLY to lactic acid (LA) as a valuable chemical was investigated in a continuous process for industrial applications. In this regard, a catalytic method using heterogeneous Cu nanoparticles in NaOH solution was studied in a microreactor by a CFD simulation. A seven-inlet micromixer comprising an optimized mixing unit was incorporated for uniform distribution of the species. The effects of...