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Optimization of the Pulp and Paper Mill Wastewater Treatment System from Recycling with the Aim of Reducing COD by Conducting a Laboratory Pilot Plant
, M.Sc. Thesis Sharif University of Technology ; Raie, Mohammad (Supervisor)
Abstract
Paper and cardboard waste pulping consume large volumes of water, so the discharge of this effluent without proper treatment can have far-reaching environmental consequences. The color and variable COD concentration of wastewater in this industry make treating this wastewater complicated. Therefore, this study aims to reduce the COD of the wastewater treatment plant of a pulp and paper mill under different laboratory conditions to achieve environmental standards in Iran.In this study, coagulation-flocculation and the Fenton process on the wastewater entering the treatment plant were investigated first. It was found that coagulation and flocculation by 750-1250 ppm of alum coagulant and ten...
Effect of Selected Promotors on the Electrocatalytic Performance in Oxygen Evolution Reaction
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Cyrus (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
Abstract
During the last few decades, efforts have been made to replace fossil fuels with clean and non-absorbent energy sources. One of the promising strategies is energy production by hydrogen storage using water splitting. For this purpose, different methods of using light, heat and electricity are provided. Electrolysis of water with a simple environment such as very high purity of hydrogen produced, controllable, device, no need for high temperature and pressure in the reactor and huge potential for industrial applications has been very much considered. Water electrolysis consists of two reactions: reduction of water to hydrogen (HER) and oxidation of water to oxygen (OER). The second reaction...
Preparation of New Titanium Nitride-Carbon Nanocomposites and Evaluation of their Electrocatalytic Behavior
, Ph.D. Dissertation Sharif University of Technology ; Ghorbani, Mohammad (Supervisor) ; Dolati, Abolghasem (Supervisor)
Abstract
Titanium nitride-carbon nanocomposites are synthesized by the reaction of TiCl4 and NaN3 in supercritical benzene medium that also serves as a carbon source. In order to improve the crystallinity of the as-prepared precursor (SI), it is further heat-treated at 1000 ˚C for 3-10 h using anhydrous ammonia and UHP nitrogen atmospheres at 1000 ˚C (SIII-SV). Moreover, to improve electrochemical behavior, the synthesized nanocomposite (SIV) is modified with Pt nanoparticles using a polyol process. For better understanding of synthesized catalyst nature and justifying their variant ORR activity several analyses are done. X-ray diffraction (XRD), Raman spectrum, field emission scanning electron...
Biological Treatment of Dairy Wastewater (Anaerobic/Anoxic/Aerobic)
, M.Sc. Thesis Sharif University of Technology ; Alemzadeh, Iran (Supervisor) ; Vosoughi, Manouchehr (Supervisor)
Abstract
In this research, start-up, performance and stability of a A2O system (Anaerobic/ Anoxic/ Oxic) combined with a Moving Bed Bio Reactor (MBBR), using Kaldnes packings, have been investigated in treating synthetic dairy wastewater. Also the effect of influent Chemical Oxygen Demand (COD), Hydroulic Retention Time (HRT) and Ruturn Activated Sludge (RAS) ratio on removing pollutants such as COD, Total Nitrogen and Total Phosphorous have been studied. The experiments have been designed using ‘Design Of Experiments’ software, and at the end the results have been optimized based on desired terms. The performance and capability of the reactor in removing pollutants in 8, 12 and 16 hours of HRT,...
Kinetic and Mechanistic Study of Oxidation of Dopamine by Manganese (IV) Clusters with Relevance to Photosystem II
, M.Sc. Thesis Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
Studying of synthetic models which have many similarities to Oxygen Evolving Complex (OEC) in Photosystem II (PS II) can play a very significant role in gaining an insight to mechanism of oxidation of water in PS II. The aim of this study is to investigate the mechanistic and kinetic aspects of oxidation of dopamine as an important neurotransmitter in body by tri and tetranuclear oxo-bridge manganese clusters which have been reported in the past to get some information about the influence of protonation and deprotonation of oxo-bridges and water molecules bonded to these clusters on properties of them in redox reactions.In aqueous media, the trinuclear complex...
Performance Comparison of Membrane Bioreactor and Activated Sludge Processes in Starch Wastewater Treatment
, M.Sc. Thesis Sharif University of Technology ; Shayegan, Jalaledin (Supervisor)
Abstract
In this study the performance of the conventional activated sludge and the membrane bioreactor systems were investigated and their operations were compared. . A membrane bioreactor and a conventional activated sludge system which includes one aeration basin and one settling tank were designed and constructed. The feed was synthetic and the BOD:N:P ratio was 100:5:1. In order to starting the systems, the sludge supplied from the municipal wastewater treatment plant and inoculated. Then, the inoculated sludge was adapted to treat the starch wastewater with step by step increasing the feed COD. . The performance of two systems investigated in inlet COD=2500 mg/L and four hydraulic retention...
Evaluation of Vermifilter Efficiency in Petroleum Wastewater Treatment (BTEX)
, M.Sc. Thesis Sharif University of Technology ; Torkian, Ayub (Supervisor) ; Mirzai, Mohammad (Supervisor)
Abstract
The aim of this thesis was to find the optimum retention time for treatment of synthetic petroleum wastewater by a wastewater treatment system made with a bucket, mineral material and earthworms residing in a vermibed. In order to make the desired flow happen, height difference was utilized. The polluting substance used for making wastewater was BTEX. As the wastewater was synthetic, the concentration was also a variable. The ultimate soluble concentration was 3200 mg/l and more concentrations were not tested. Parameters such as number of worms, worm’s growth rate and their distribution pattern, humidity amount and distribution and worm’s acclimatization time during organic loading shock...
Modeling of Biological Matter Cycling in Shallow Lake by System Dynamic Method
, M.Sc. Thesis Sharif University of Technology ; Abrishamchi, Ahmad (Supervisor)
Abstract
Modeling of water quality in shallow lake is the goal of this roject.Matters cycling in environment will be explained. The dissolved Oxygen will be assigned the most important factor in water quality. The phytoplankton Growth rate and fatality rate will be modeled By LOTKAVOLTERRA equations. The nitrification by nitrifying bacteria and Michael Menton equations will be explained. Modeling will be executed By System Dynamic which feedbacks are the most com ponents of it.The model will be built with equations and coefficients in literatures and this model run by VENSIM®software. We will assure by some extreme condition tests about the structure of the model and finally we will make a...
Investigation of Water Splitting Performance of Zeolitic Imidazolate Framework-67 and Graphene Quantum Dots Composite
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Depleting resources and heavy pollution of fossil fuels have drawn the world's attention to clean energy and the most ideal one is hydrogen. Water splitting is one of the most effective ways to produce hydrogen and due to slow kinetic rate different kind of catalysts (optical, electrochemical, etc.) are developed for this reaction. In this work a ZIF-67 and N-doped graphene quantum dots composite is developed and its electrocatalytic performance in oxygen evolution reaction is evaluated. The synthesized graphene quantum dots are between 2-4 nm and the incorporation of nitrogen atom in their structure was verified by FTIR analysis. The metal-organic framework which is produced in this work...
Optimization of Hybrid Anaerobic/Aerobic Bioreactor for Phosphate Removal
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Discharging treated or raw waste water in to surface water may cause lots of serious problems, including growth of algae, as a result of the presence of nutrients in waste water.algae decrease the concentration of dissolve oxygen in water.phosphorus removal from waste water is of absolute necessity. according to the standards set by the environmental organization, discharge the untreated waster water in to the surface water is not allowed. on the other hand, given manager facilities of deprived area,effort is channeled to reach the desired result through designing the simplest treatment systems. anaerobic-aerobic systems have remarkably been used for many years in the treatment of urban and...
Investigation of Textile Dyeing Wastewater Treatment by Vermifiltration and Troubleshooting and Modification of the Chemical/Biological Treatment Plant of the Ekbatan Textile Factory
, M.Sc. Thesis Sharif University of Technology ; Hashemian, Jamaloddin (Supervisor) ; kalhor, Hamid Reza (Supervisor)
Abstract
Water is the essence of life. On average, a human being consumes about 2 liters of water every day and it accounts for about 70% of the weight of human body and this alone reflects the importance of water for continuation of life. The production process in textile and dyeing factories as increasingly growing industrial units consume large amounts of water and consequently produce large volumes of wastewater. Such industries face environmental regulations on one hand and are unable to compete with foreign products on the other since the imported counterparts are low-priced. Therefore, finding a cost-effective and efficient solution for treatment of waste water and troubleshooting and...
Development of Nanostructured Lithium-Rich Cathode Material
, Ph.D. Dissertation Sharif University of Technology ; Sadrnezhaad, Khatiboleslam (Supervisor)
Abstract
This research is divided in three parts. In the first part of this research, we report the one-pot synthesis of carbonate-coated nanostructured LLO (Li2CO3@LLO) through a polyol-assisted method as a Li-ion battery cathode. Carbonate protects the cathode from adverse reactions with the electrolyte, also reduces the layered-to-spinel phase transition, thereby stabilizing the cathode structure. LLO nanostructure provides a fast Li+ diffusion. The target material exhibits excellent long-term stability with 77% capacity retention after 1000 cycles at 0.2C-rate. In the second part of research, Li(Na-doped)-Mn-Ni-O oxides were synthesized by different LiOH.H2O amount, type and amount of reducing...
Design, Fabrication, and Application of Nickel Oxide-Base Nanostructured Electrocatalysts for the Production of Oxygen And Hydrogen from Seawater
, Ph.D. Dissertation Sharif University of Technology ; Moshfegh, Alireza (Supervisor) ; Moradlou, Omran (Supervisor)
Abstract
Hydrogen is emerging as a clean and ideal fuel. However, its dependency on freshwater resources will be a threat to a sustainable environment. Considering the abundance of seawater and the scarcity of freshwater resources, direct electrolysis of seawater to produce hydrogen fuel can be a promising and potential alternative to pure water electrolysis technologies. Seawater contains electrochemically active ions with the nature of competition with the oxidation reaction of water, thus affecting the catalytic activity and, subsequently, the selectivity. From the thermodynamic and kinetic aspect in the electrolysis of seawater, the unfavorable reaction related to the formation of chlorine...
3d Design of a Microfluidic Chip for Anticancer Drugs Screening
, M.Sc. Thesis Sharif University of Technology ; Mashayekhan, Shohreh (Supervisor) ; Saadatmand, Maryam (Supervisor)
Abstract
Nowadays, advanced and inexpensive pre-clinical methods for investigating the effects of anti-cancer drugs are expanding. One of the latest three-dimensional laboratory modeling for evaluating the effects of drugs is the use of tumor-on-chip technology, which actually models the physiological system of the body through three-dimensional scaffolds, multicellular cultures, and shaped vascular systems. In this study, three-dimensional culture of cancer cells was performed in the form of spheroids. A chip of U-shaped microstructures with and without gaps was used to trap cells and form cancer spheroids. We simulated the simultaneous effect of drug and oxygen concentration distribution inside the...
Synthesis and Performance Evaluation of FeOOH Elechtrocatalyst Supported on Nickel Foam for Oxygen Evolution Reaction
, M.Sc. Thesis Sharif University of Technology ; Moshfegh, Alireza (Supervisor) ; Naseri, Naimeh (Co-Supervisor)
Abstract
Due to imminent shortage of fossil fuels, environmental issues that occur from their intensive use, population growth and industrialization of societies moving towards renewable energy sources is inevitable. Sun is the most clean and abundant source of energy but it is needed to be accompanied with an energy storage system as it is intermittent and cannot supply our required energies on demand. Water splitting electrochemical cells are promising solutions to cope with this problem by producing hydrogen as a clean fuel. The overpotential imposed by anode is the bottleneck of the water splitting reaction. The anodes with sufficient efficiency that are used today are made from precious and...
Fabrication of Multilayer Electrodes Based on Earth-Abundant Transition--Metal Compounds and Investigation of Their Photoelectrocatalytic Properties in Water Splitting Reaction
, M.Sc. Thesis Sharif University of Technology ; Ghasemian, Saloumeh (Supervisor) ; Taherinia, Davood (Supervisor)
Abstract
Photoelectrochemical (PEC) water splitting is exceedingly promising for converting solar energy into molecular hydrogen as a clean and sustainable fuel. However, the overall rate of water splitting reaction is severely limited by the sluggish kinetics of the anodic half-reaction, namely, the oxygen evolution reaction (OER). Bismuth vanadate (BiVO4) is a popular photoanode for PEC water splitting due to its high stability, low cost, narrow band gap (2.4 eV), high visible-light absorption, and environmental compatibility. However, BiVO4 suffers from poor charge transfer, fast recombination of electron-hole pairs, and inferior catalytic activity toward OER. An effective strategy to overcome...
Numerical Simulation of Glucose Metabolism and Hepatocyte Viability within a Microfluidic
, M.Sc. Thesis Sharif University of Technology ; Firoozabadi, Bahar (Supervisor)
Abstract
The advent of microfluidics as suitable environments for culturing cells is associated with some challenges such as shear stresses applied on the cells. In fact, hepatocytes lose their function as exposed to high shear stresses similar to other cell types. Moreover, among all factors needed for cell viability, feeding hepatocytes with adequate oxygen is of great importance due to their high demand for oxygen compared the other cells. In this thesis, different types of cultures including 2D and 3D has been used in order that shear stresses would be in allowed range and provision of hepatocytes with sufficient oxygen concentrations has been ensured as well. In addition to supplying hepatocytes...
Synthesis and Characterization of Core-shell Nanoparticles Anchored Reduced Graphene Oxide (rGO) and Kinetic Investigation of Oxygen Evolution from Water Oxidation in the Presence of these Nanocatalysts
, M.Sc. Thesis Sharif University of Technology ; Rahman Setayesh, Shaherbanoo (Supervisor) ; Taherinia, Davood (Co-Supervisor)
Abstract
The reaction of oxygen evolution, in other words, the process of water oxidation in the presence of heterogeneous photocatalysts such as g-C3N4, Co/g-C3N4 /rGO, Ni/g-C3N4/rGO, CoNi/g-C3N4 / rGO, Co2Ni1/g-C3N4/rGO, and Co1Ni2 /g-C3N4 /rGO were studied. The characterization of these nanocatalysts was done by XRD, SEM, FT-IR, BET, DRS, CHN, and TGA techniques. Thermogravimetric analysis (TGA) was used to check the thermal stability of these nanocatalysts. The FT-IR spectroscopy was used to identify the functional groups in graphitic carbon nitride and to confirm g-C3N4 synthesis. According to BET results, the pore sizes were determined which were at the nano and macro scale. It was found that...
Fabrication and Characterization of Conifecu and Three Dimensional Graphene Electrocatalyst Toward Oxygen Evolution Reaction
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Development of active, durable, cost effective, and stable electrocatalysts are of urgent need for various industrial fields including renewable energy systems such as water splitting. State-of-the-art catalysts suffer from high cost, poor catalytic activity in alkaline medium due to sluggish kinetics. We used one-step electrochemical deposition technique to prepare NiFeCu layered double hydroxide and CoNiFeCu dendritic porous structure on Ni-foam and flexible three-dimensional graphene (3DG) networks, respectively. The fabricated 3D electrodes have a high surface area, high electrical conductivity, and multiple interfaces which along with the synergetic effect of transition metals provided...
Model Systems for Oxygen – Evolving Complex in Photosystem II: Manganese Oxides and Manganese Complexes with O and N Donor Ligands
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
The aim of this study is to mimic water oxidizing complex to find new materials and also to understand their rules in this matter. To achieve this, manganese complexes containing 2,4,6-tris (2-pyridyl)-1,3,5-Triazine, 1,10-phenanthroline, 1,10-bipyridine, Schiff base, amino acids, 2,6-pyridinedicarboxylic acid, 2-pyridinecarboxylic acid have been synthesized and characterized by elemental analysis, IR, EPR, ESI-MS, electronic absorption spectroscopy, electrochemistry, X-ray diffraction and oxygen evolution in presence of oxone and Ce(IV). It is shown that the reaction between Mn(II) complexes containing 2,4,6-tris¬(2-pyridyl)-1,3,5-Triazine, 1,10-phenanthroline, 1,10-bipyridine,...