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environmental-pollutions
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Modified Zeolitic Nanostructures: Synthesis, Characterization and the Investigation of Their Catalytic-Sorption-Antibacterial Applications
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Gobal, Fereydoun (Co-Advisor)
Abstract
Modified zeolitic nanostructures were prepared by sol-gel, hydrothermal and coprecipitation methods. At first step, natural zeolite was used as a support for preparing the Ag/AgBr/TiO2 photocatalysts. Their photocatalytic properties were studied by degradation of pollutants and microorganism inactivation at the presence of different illumination source. These processes were mechanistically investigated and the results were explained. At second step, mordenite anocrystals, which synthesized by hydrothermal method, were used as an effective support to prepare the AgX/TiO2/MOR photocatalysts. Photocatalytic degradation of an azo dye performed over these nanocomposites and a mechanism suggested...
Synthesis of Zeolite-Based NanoComposites and Investigation of their Catalytic Activities
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
Polyagent photocatalysts based on the zeolite including TiO2, Ag and AgBr prepared by Sol-gel method. Ag and AgBr prevent of electron-hole recombination and enhance photocatalytic activity. Prepared catalysts were characterized by different analysis method including XRD, SEM, EDX, FTIR and BET techniques. Catalyst activities were investigated from two aspects: in first step the activities of catalyst were investigated for degradation of AB92 dye. The effect of different factors such as: catalyst concentration, dye concentration, pH and scavenger (sodium thiosulphate) on efficiency and reaction rate were investigated. The optimazed values for all conditions specified, then catalyst activities...
Pollution Cost assessment of Energy Systems; Case Study: Guilan Province
, M.Sc. Thesis Sharif University of Technology ; Saboohi, Yadollah (Supervisor)
Abstract
The energy section has a significant share in the emission of environmental pollutants. Based on the recent investigations about 80 percent of greenhouse gases are emitted into the environment from this sector. This present research has focused on estimating costs of pollution control, using the energy system model. In order to have a better understanding of the relationship between energy and environment, the reference energy system for Guilan Province has been developed; then by having energy demand data, historical capacity data for each technologies and potential of energy resources as well as, the development of provincial energy system has been studied. After the model verification and...
Kinetics Investigation of Environmental Pollutants Degradation in Advanced Oxidation Processes Using Metal Oxide Nanocatalysts
, Ph.D. Dissertation Sharif University of Technology ; Rahman Setayesh, Shahrbanoo (Supervisor)
Abstract
In this project, metal oxides loaded on different supports were used in the heterogeneous electro-Fenton (EF) process for organic pollutants removal. At first, Fe3O4/AC was synthesized for catechol degradation as a phenolic compound. 98.2% removal of catechol was achieved by operational conditions optimization. The catalytic activity of Fe3O4/AC was remained constant after 6 cycles. In the other study, reduced graphene oxide was used as a support for the magnetite nanoparticle catalyst. The catalytic activity of Fe3O4/rGO in EF degradation of reactive red 195 (RR195) dye was studied and 93.34% removal was obtained. Response surface methodology (RSM) was used and a quadratic model with...
The Impact of Environmental Pollutants on Housing Valuation in Iranian Metropolises
, M.Sc. Thesis Sharif University of Technology ; Keshavarz Haddad, Gholamreza (Supervisor)
Abstract
In this study, we intend to investigate the effect of pollution levels on the valuation of residential units in Tehran. The method used in this research is Hadanik pricing method. Data required for the project, in relation to the intrinsic characteristics of housing including number of bedrooms, building life, area and… air pollution index by regional stations on a daily basis and housing environmental characteristics including per capita green space, day and night pollution index, density The population of the area and… are collected. According to the results, they have the greatest impact on determining the value of the building area and building life, and after controlling for other...
Synthesis and Characterization of Modified Nanocomposites Using MOFs for Studying the Kinetics, Thermodynamics, and Mechanism of Removal Environmental Pollutants
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Rahman Setayesh, Shahrbanoo (Co-Supervisor)
Abstract
With the development of urbanization, industrialization, explosive population growth, and environmental degradation, the world is facing a serious challenge of water pollution. Nowadays, the water-soluble pollutant such as heavy metals and dyes brought a serious threat to the aquatic organisms and human health due to their non-degradability and carcinogenicity.With the purpose of future security and to restore ecological balance, it is essential to give much significance towards the removal of unwanted toxic contaminants from water resources. In this regard, the removal of toxic pollutants from wastewater using Metal-organic frameworks (MOFs) -based composites is considered as one of the...
Kinetics Investigation of the Degradation of Environmental Pollutants by Electro-Fenton Processes Using Iron Vanadate Nanoparticles
, M.Sc. Thesis Sharif University of Technology ; Rahman Setayesh, Shahrbanoo (Supervisor)
Abstract
Nanocomposite FeVO4/CeO2 was synthesized by hydrothermal method and was applied for removal of methyl orange. This nanocomposite was characterized by SEM, FT-IR, XRD, BET methods. SEM images showed that FeVO4 nanorode decorated on CeO2 spherical particles. The results of XRD patterns confirmed the triclinic structure for Fe(III)vanadate and the cubic fluorite structure for cerium oxide. The surface area of FeVO4, CeO2 and FeVO4/CeO2 was determined by BET analysis which the results represented an increase in surface area in nanocomposite using cerium oxide as support. The electro-Fenton reaction was performed in undivided electrochemical reactor using stainless steel electrodes and the...
Criteria of Choosing Intersection or Roundabout Based on Delay Time, Fuel Consumption, and Environmental Factors
, M.Sc. Thesis Sharif University of Technology ; Nassiri, Habibollah (Supervisor)
Abstract
Nowadays, there are three factors in traffic issues, which are very important. These factors are delay time, fuel consumption and environmental pollution. A good choice of the type of traffic nodes (intersection and roundabout) can play an important role in reducing some of the traffic problems such as: the amount of vehicles' delay time, energy consumption and pollution due to the transport system. In this study, we try to identify factors that influence delay time, fuel consumption and air pollution in different types of intersections and roundabout. According to previous studies, these factors were such as: variables of each route volume, distribution of through, right turn and left turn...
Comparison of Performance of Rice Husk Ash in Cement Mixtures Compared with other Artificial Pozzolan
, M.Sc. Thesis Sharif University of Technology ; Khalu, Alireza (Supervisor)
Abstract
Growing production of cement and concrete in developing countries like Iran in addition to high amounts of energy consumption and pollutants formation through production of cement has motivated researchers to partially replace it with suitable additive materials. In this study, the chemo-physical and microstructural properties of rice husk ash as an agricultural waste and its performance in cement mixtures as a pozzolan is experimentally investigated. Parameters influencing the pozzolanic properties of this material that are studied include the effect of acid leaching before pyro-processing, heating rate, temperature, retention time, and cooling rate. Additionally, this material is compared...
Kinetics Investigation of Photocatalytic Degredation of Environmental Organic Pollutants Using ZnO-Zeolite Nano Composites
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Sajadi, Ali Akbar (Supervisor)
Abstract
ZnO nano particles and mordnite zeolite nano particles were prepared by precipitation method and hydrothermal method,respectively. The influence of solvent and surfactant in ZnO nano particles synthesis were studied to reform the structure of nano particles.These nano particles were based on different supports to improve and enhance their photocatalytic activities. Synthesized catalysts characterized by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform-infra red spectra (FTIR), UV-Vis spectroscopy and BET techniques. To investigated photocatalytic activity of the synthesized catalysts under UV irradiation, they were used to degradation bio-environmental...
Novel Photocatalysis Systems: Preparation, Characterization and Kinetics Investigation of Environmental Pollutant Degradation
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor) ; Tasviri, Mahboobeh (Co-Advisor)
Abstract
Nanophotocatalysts containing metal oxides and oxy-acids based on the nanoporous materials such as graphene, metal-organic-frameworks and carbon nano tubes were synthesized. The photocatalytic properties of the prepared samples were evaluated by the photodegradation of different pollutants in the suspension and emulsion photocatalytic systems. This study demonstrates a new kind of photocatalytic system via utilization of the superior specific properties inherent in Pickering emulsion. We designed the new photocatalytic system using a photocatalytic active component and hydrophobic conducting nanostructures to form the stabilized Pickering emulsion (Pe-bp system). The results revealed that...
On The Chemo-Physical and Microstructural Properties of Rice Husk Ash and Its Performance in Cement Mixtures
, M.Sc. Thesis Sharif University of Technology ; Khalu, Alireza (Supervisor)
Abstract
Growing production of cement and concrete in developing countries like Iran in addition to high amounts of energy consumption and pollutants formation through production of cement has motivated researchers to partially replace it with suitable additive materials. In this study, the chemo-physical and microstructural properties of rice husk ash as an agricultural waste and its performance in cement mixtures as a pozzolan is experimantally investigated. Parameters influencing the pozzolanic properties of this material that are studied include the effect of acid leaching before pyro-processing, heating rate, retention time, and grinding time. Additionally, this material is compared with other...
The Kinetic and Mechanism Evaluation of Photocatalytic Degradation of Environmental Pollutants Using Modified Nanocomposites
, Ph.D. Dissertation Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
Different nanocomposites were prepared based on the carbon nitride, structures and metal organic framework. The photocatalytic activities of a group of metal-organic metal frameworks were evaluted. Next step, the combination of binary and ternary composites based on carbon nitride/metal-organic frameworks structures with other semiconductors such as oxyacid, bismuth oxy halide and ferrite spinel was used. In addition, synthesis of varius type of metal oxides structures with metal organic framework precursors has also been another perpuse of this thesis.The catalytic and photocatalytic activities of designed nanocomposites were performed for a redox process (4-nitrophenol (4-Nip) to...
Experimental Investigation of Mechanical Behavior of Structural Concrete with Combination of Waste Glass and Silica Fume
, M.Sc. Thesis Sharif University of Technology ; Khaloo, Ali Reza (Supervisor)
Abstract
Concrete is the second most structural material in the world. So attention and promotion of the concrete mix design with respect to variable issues and requirements, is very important. On the other hand, these days environment and its pollution has become very popular discussion. Waste-glass which is produced by human products is one of the environmental pollutants. In this thesis it replaces some aggregate in concrete and it can reduce the level of this material in the world. Also we study effects of silica-fume as cement replacement and properties enhancer in our concrete mix design and see how it can ...
Novel Sol Gel– and Electrospun– Based Nanostructure Sorbents for Extraction of Drugs and Pollutants
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor)
Abstract
The main purpose of this dissertation was to synthesize nanostructured adsorbents based on the sol–gel and electrospinning methods and implement them to the trace determination of the desired analytes from different matrices. In the first and second chapters, a summary of the sol–gel and electrospinning methods along with a glance on extraction methods are presented. Then, the implemented projects are presented in the consecutive chapters.In the first work, third chapter, silica nanofibers were successfully produced using electrospinning method. In this process, sol–gel was formed during electrospinning and then, the backbone polymer was removed by heating. To obtain a thin layer of silica...
Kinetics Investigation of the Degradation of Environmental Pollutants by Fenton and Electro-Fenton Processes using Nanomagnetite and Nano Magnetite Supported by Activated Carbon
, M.Sc. Thesis Sharif University of Technology ; Rahmansetayesh, Shahrbano (Supervisor)
Abstract
The progress and the development of various industries, pollutants derived from the agricultural and industrial processes contaminate the environment. The degradation of these pollutants have an important effect on the environment.Magnetite (Fe3O4) nanoparticles and magnetite supported on functionalized activated carbon were synthesized and characterized by different techniques such as SEM, FT-IR, XRD, BET and VSM. The catalyst activity of these nanocatalysts was evaluated by the degradation of reactive red ME4BL (RRME4BL) textile dye in heterogeneous Fenton and electro-Fenton processes as a model pollutant. The effect of several parameters such as H2O2, RRME4BL concentration, the amount of...
Polyhedral Oligomeric Silsesquioxanes based Materials as Sorbent and Sensor
, Ph.D. Dissertation Sharif University of Technology ; Bagheri, Habib (Supervisor) ; Jamali, Sirous (Supervisor)
Abstract
The main approach in this thesis is the synthesis and identification of polyhedral oligomeric silsesquisans (POSS) and their modification with suitable functional groups to induce desired properties and use them as adsorbents or sensor. In the first work, POSSs were used as three-dimensional porous compounds with special properties as extractant phase in solid phase croextraction. Selective extraction of polar and non-polar molecules to particle size and functional groups on POSS. In this research, a threedimensional network of POSS including naphthalene diimide (POSS-NDI) and perylene diimide (POSS-PDI) as an extractant phase capable of absorbing volatile organic compounds was used to...
Impact of Oxygen-enriched Air Combustion by Membrane System on Performance of Diesel Engine and Air Pollutants Emission
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor)
Abstract
Oxygen enriched combustion is one of the attractive combustion technologies to control pollution and improve combustion in diesel engines. In the present work after an introduction to membrane seperation and membrane seperators for oxygen-nitrogen from air, a simulation of combustion chamber by GT-Power and membrane COMSOL Multiphysics was used to study the impact of oxygen enrichment on combustion, pollution and performance parameters with 23, 25 and 27% levels of enrichment. Increasing the oxygen engine content with the air leads to faster burn rates and the ability to burn more fuel at the same stoichiometry. These effects have the potential to decrease specific fuel consumption and...
Synthesis of Modified Nanocomposite Based on Metal Organic Frameworks for Kinetic Study of Environmental Pollutant Elimination
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
An environmentally friendly heterogeneous ternary carbon dots (CDs)/MIL-88B (Fe)/Bi2S3 nanocomposite was synthesized by a multistep method. In this study, we have studied low-temperature calcination with relatively inexpensive reactants. Fabricated nanocomposite structures were characterized by FT-IR, XRD, EIS, SEM, BET, and TGA techniques, demonstrating the decoration of the Bi2S3 on the CDs/MIL-88B (Fe) nanocomposite surface. MOF templating has been chosen as a systemic method for limited size CD formation inside MIL-88B (Fe) pores. The CD arrays also revealed an excellent efficacy for catalytic and photocatalytic applications. According to the experimental results, CDs/MIL-88B (Fe)/Bi2S3...
A Superhydrophobic Melamine Formaldehyde Sorbent for Micro Extraction of Pollutants from Aquatic Media
,
M.Sc. Thesis
Sharif University of Technology
;
Bagheri, Habib
(Supervisor)
Abstract
In this project, melamine formaldehyde was chosen as initial substrate for its high porosity. Then for having superhydrophobic surface, surface functional groups were silanized and deactivated as a result. It was assumed that high porosity of prepared sorbent and its nonpolar nature, can increase extraction efficiency. To study extraction efficiency of the prepared sorbent, it was filled inside a needle and used for needle-trap head-space extraction of BTEX (abbreviation for Benzene, Toluene, Ethylbenzene and Xylenes). Needle packed with sorbent was held on headspace of sample containing BTEX and head- space was pumped with a peristaltic pump. Pumping introduces fresh sample to sorbent...