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Choosing a Suitable Microalgae for Bioremediation of Heavy Metals Regarding Iran's Clamate
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
The pollution of water resources with heavy metals as a result of industrial activities threatens the lives of all living organisms. Therefore, separation of heavy metals from wastewater before entering our invironment is very important. Various chemical and physical methods such as absorption, chemical precipitation, extraction by solvent and ion exchange can be used to separate heavy metals but each of these methods have their own problems such as imperfect separation of heavy metals, need for expensive facilities and refining systems, high energy consumption and leaving pollutant residuals that need to be separated. On the other hand, the methods mentioned above can not separate heavy...
Mathematical Modeling of Upflow Biofilm Reactor for Wastewater Treatment
, M.Sc. Thesis Sharif University of Technology ; Yaghmaee, Soheila (Supervisor) ; Kariminiaye Hamedani, Hamid Reza (Supervisor)
Abstract
By increasing of population, migration to urban area and industrial development, the concern of environmental pollution becomes more important. Wastewaters are one of the polluting agents which should be collected, treated and reused in a safe and healthy condition. Generally wastewater treatment systems are classified into two major groups, namely aerobic and anaerobic treatment systems.Anaerobic fixed bed reactors are used for decreasing the organic load of wastewater. Enhancement of microbial retention time by attaching the organisms to packings is the most significant advantage of this bioreactor which increases the removal efficiency of organic materials of strength wastewater.In this...
A zwitterion metal-organic framework for the removal of fluoride from an aqueous solution
, Article Journal of Chemical Sciences ; Volume 134, Issue 3 , 2022 ; 09743626 (ISSN) ; Gholami, R. M ; Borghei, S. M ; Sharif University of Technology
Springer
2022
Abstract
Excess fluoride is one of the water pollutants in the world, which is removed from water by chemical methods to produce sludge. On the other hand, techniques such as R.O. (Reverse Osmosis) also have problems with power consumption and wastewater disposal. Metal-organic frameworks are one of the newest adsorbents used to separate anions. In this study, MOF1 ({[Zn3L3(BPE)1.5]·4.5DMF}n) was used to remove fluoride from the aqueous solution. The influence of various factors such as pH, contact time, adsorbent amount, and temperature on fluoride uptake was investigated. Based on the results, the MOF synthesized in acidic media absorbs more fluoride ions. The reaction time in the first 20 min had...
Synthesis, Characterization and Applications of Antibacterial Metal-Organic Framework Nanocomposites for Water Remediation
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Yaghmaei, Soheila (Supervisor) ; Ghobadi Nejad, Zahra (Co-Supervisor)
Abstract
Contaminants in drinking water, including microbial contaminants, have a great impact on the health of people in the community and can seriously threaten public health. In recent years, diseases caused by pathogenic bacteria due to the consumption of contaminated water have led to many deaths. As a result, water treatment has been one of the most important human concerns. Among the new water treatment technologies, metal-organic(MOF) frameworks are a new generation of porous materials that have properties such as high surface area, water stability and functionality due to their dual structure. As a result, they are widely used today in various scientific fields, including water purification....
A highly thermal-resistant electrospun-based polyetherimide nanofibers coating for solid-phase microextraction Microextraction Techniques
, Article Analytical and Bioanalytical Chemistry ; Vol. 406, issue. 8 , March , 2014 , p. 2141-2149 ; Akbarinejad, A ; Aghakhani, A ; Sharif University of Technology
Abstract
A high-temperature-resisant solid-phase microextraction (SPME) fiber was prepared based on polyetherimide (PEI) by the electrospinning method. The PEI polymeric solution was converted to nanofibers using high voltages and directly coated on a stainless steel SPME needle. The scanning electron microscopy images of PEI coating showed fibers with diameter range of 500-650 nm with a homogeneous and smooth surface morphology. The SPME nanofibers coating was optimized for PEI percentage, electrospinning voltage, and time. The extraction efficiency of the coating was investigated for headspace SPME of some environmentally important polycyclic aromatic hydrocarbons from aqueous samples followed by...
A supervisory control policy over an acoustic communication network
, Article International Journal of Control ; Volume 88, Issue 5 , Dec , 2015 , Pages 946-958 ; 00207179 (ISSN) ; Dumon, J ; Canudas De Wit, C ; Sharif University of Technology
Taylor and Francis Ltd
2015
Abstract
This paper presents a supervisory multi-agent control policy over an acoustic communication network subject to imperfections (packet dropout and transmission delay) for localisation of an underwater flow source (e.g., source of chemical pollution, fresh water, etc.) with an unknown location at the bottom of the ocean. A two-loop control policy combined with a coding strategy for reliable communication is presented to perform the above task. A simulator is developed and used to evaluate the trade-offs between quality of communication, transmission delay and control for a fleet of autonomous underwater vehicles supervised over a noisy acoustic communication network by an autonomous surface...
Overview on the separation and removal of Haloaceticacid'S in drinking water
, Article 4th WSEAS International Conference on Waste Management, Water Pollution, Air Pollution, Indoor Climate, WWAI '10, 3 May 2010 through 6 May 2010, Sousse ; 2010 , Pages 25-31 ; 9789604741908 (ISBN) ; Soltanieh, M ; Mosavi, M ; Sharif University of Technology
2010
Abstract
The increase of pollution and the expansion of industrial, agricultural wastewater and urban runoff discharges in water sources have intensified the concentration of water pollutants. Considering that in Iran as in other countries the major part of drinking water is obtained from surface waters and due to the importance of disinfection, chlorination is doubtlessly the optimum and most common water treatment method used. However this method produces chlorination by-products (CBPs). Trihalomethanes(THMs) and Haloaceticacids (HAAs) are the main and most important groups of disinfection by-products (DBPs). Separation of THMs has gained a lot of breakthroughs since a lot of time elapses from its...
Evaluation of permeable pavement responses to urban surface runoff
, Article Journal of Environmental Management ; Volume 187 , 2017 , Pages 43-53 ; 03014797 (ISSN) ; Delkash, M ; Tajrishy, M ; Sharif University of Technology
Academic Press
2017
Abstract
The construction of permeable pavement (PP) in sidewalks of urban areas is an alternative low impact development (LID) to control stormwater runoff volume and consequently decrease the discharge of pollutants in receiving water bodies. In this paper, some laboratory experiments were performed to evaluate the efficiency of a PP subjected to sediment loadings during its life span. Simple infiltration models were validated by the laboratory experiments to evaluate the trend and extend of PP infiltration capacity throughout the life of the pavement operation. In addition, performances of the PP in removing total suspended solids (TSS) and selective nutrient pollutants such as NO3 −, NH4 + and...
Remediation of trapped DNAPL enhanced by SDS surfactant and silica nanoparticles in heterogeneous porous media: experimental data and empirical models
, Article Environmental Science and Pollution Research ; Volume 27, Issue 3 , 2020 , Pages 2658-2669 ; Khasi, S ; Fatemi, M ; Ghazanfari, M. H ; Sharif University of Technology
Springer
2020
Abstract
The remediation of nonaqueous phase liquids (NAPLs) enhanced by surfactant and nanoparticles (NP) has been investigated in numerous studies. However, the role of NP-assisted surfactants in the dissolution process is still not well discussed. Besides, there is a lack of empirical dissolution models considering the effects of initial residual saturation Strap, NAPL distribution, and surfactant concentration in NAPL-aqueous phase systems. In this work, micromodel experiments are conducted to quantify mass transfer coefficients for different injected aqueous phases including deionized water, SDS surfactant solutions, and NP-assisted solutions with different levels of concentrations and flow...
Trichloroethylene degradation by PVA-coated calcium peroxide nanoparticles in Fe(II)-based catalytic systems: enhanced performance by citric acid and nanoscale iron sulfide
, Article Environmental Science and Pollution Research ; Volume 28, Issue 3 , 2021 , Pages 3121-3135 ; 09441344 (ISSN) ; Shan, A ; Sun, Y ; Gu, X ; Lyu, S ; Zhou, Y ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this study, the enhanced trichloroethylene (TCE) degradation performance was investigated by polyvinyl alcohol coated calcium peroxide nanoparticles (PVA@nCP) as an oxidant in Fe(II)-based catalytic systems. The nanoscale iron sulfide (nFeS), having an average particle size of 115.4 nm, was synthesized in the laboratory and characterized by SEM, TEM, HR-TEM along with EDS elemental mapping, XRD, FTIR, ICP-OES, and XPS techniques. In only ferrous iron catalyzed system (PVA@nCP/Fe(II)), TCE degradation was recorded at 58.9% in 6 h. In comparison, this value was increased to 97.5% or 99.7% with the addition of citric acid (CA) or nFeS in PVA@nCP/Fe(II) system, respectively. A comparative...
Trichloroethylene degradation by PVA-coated calcium peroxide nanoparticles in Fe(II)-based catalytic systems: enhanced performance by citric acid and nanoscale iron sulfide
, Article Environmental Science and Pollution Research ; Volume 28, Issue 3 , 2021 , Pages 3121-3135 ; 09441344 (ISSN) ; Shan, A ; Sun, Y ; Gu, X ; Lyu, S ; Zhou, Y ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2021
Abstract
In this study, the enhanced trichloroethylene (TCE) degradation performance was investigated by polyvinyl alcohol coated calcium peroxide nanoparticles (PVA@nCP) as an oxidant in Fe(II)-based catalytic systems. The nanoscale iron sulfide (nFeS), having an average particle size of 115.4 nm, was synthesized in the laboratory and characterized by SEM, TEM, HR-TEM along with EDS elemental mapping, XRD, FTIR, ICP-OES, and XPS techniques. In only ferrous iron catalyzed system (PVA@nCP/Fe(II)), TCE degradation was recorded at 58.9% in 6 h. In comparison, this value was increased to 97.5% or 99.7% with the addition of citric acid (CA) or nFeS in PVA@nCP/Fe(II) system, respectively. A comparative...
Composite of methyl polysiloxane and avocado biochar as adsorbent for removal of ciprofloxacin from waters
, Article Environmental Science and Pollution Research ; Volume 29, Issue 49 , 2022 , Pages 74823-74840 ; 09441344 (ISSN) ; Lima, E. C ; Benetti, A. D ; Thue, P. S ; Lima, D. R ; Sher, F ; dos Reis, G. S ; Rabiee, N ; Seliem, M. K ; Abatal, M ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Two carbon composite materials were prepared by mixing avocado biochar and methyl polysiloxane (MK). Firstly, MK was dissolved in ethanol, and then the biochar was added at different times. In sample 1 (R1), the time of adding biochar was immediately after dissolving MK in ethanol, and in sample 2 (R2), after 48 h of MK dissolved in ethanol. The samples were characterized by nitrogen adsorption/desorption measurements obtaining specific surface areas (SBET) of 115 m2 g−1 (R1) and 580 m2 g−1 (R2). The adsorbents were further characterized using scanning electron microscopy, FTIR and Raman spectroscopy, adsorption of vapors of n-heptane and water, thermal analysis, Bohem titration, pHpzc, and...
Preparation of new MOF-808/chitosan composite for Cr(VI) adsorption from aqueous solution: Experimental and DFT study
, Article Carbohydrate Polymers ; Volume 288 , 2022 ; 01448617 (ISSN) ; Shahsavari, S ; Akbarzadeh, E ; Gholami, M. R ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In this study, a series of Zirconium-based MOF and chitosan composites (MOF-808/chitosan) were synthesized as efficient adsorbent for Cr(VI) ions elimination from aqueous solution. MOF-808/chitosan structure and morphology was characterized by FE-SEM, EDX, XRD, BET, zeta potential analysis, FT-IR, XPS techniques. The kinetic studies ascertained that Cr(VI) adsorption over MOF-808/chitosan followed pseudo-second-order kinetic model. The adsorption isotherms fitted the Langmuir isotherm model, implying on homogeneously adsorption of Cr(VI) on the surface of MOF-808/chitosan. According to the Langmuir model, the maximum capacity was obtained to be 320.0 mg/g at pH 5. Thermodynamic investigation...
Efficient removal of heavy metal ions from aqueous media by unmodified and modified nanodiamonds
, Article Journal of Environmental Management ; Volume 316 , 2022 ; 03014797 (ISSN) ; Molavi, H ; Peyghambari, A ; Shojaei, A ; Rezakazemi, M ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
Academic Press
2022
Abstract
This article deals with the adsorption performances of the unmodified nanodiamond (ND) and thermally oxidized nanodiamond (Ox-ND) for the removal of different heavy metal ions such as Fe (III), Cu (II), Cr (VI), and Cd (II) from wastewater. The adsorption capacities of the ions onto adsorbents are higher and follow the order: Ox-ND-3 > Ox-ND-1.5 > ND, which is consistent with their surface areas, zeta potentials, and the presence of carboxyl groups, suggesting that electrostatic attractions between the positive metal ions and the negatively charged adsorbents are the predominant adsorption mechanisms. Adsorption capacities of these adsorbents were found to be 26.8, 31.3, and 45.7 mg/g for Fe...
UiO-66 metal–organic frameworks in water treatment: A critical review
, Article Progress in Materials Science ; Volume 125 , 2022 ; 00796425 (ISSN) ; Molavi, H ; Rezakazemi, M ; Tajahmadi, S ; Bahi, A ; Ko, F ; Aminabhavi, T. M ; Li, J. R ; Arjmand, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
Metal-organic frameworks (MOFs) have recently achieved much attention to eliminating toxic pollutants because of their attractive attributes, including large specific surface area, ultra-high porosity, abundant active adsorption sites, tunable surface chemistry, well-controlled pore size distribution, and strong host–guest interactions. Among the many developed MOFs, the Zr-based MOFs, particularly the UiO-66 family, are considered extremely attractive for wastewater treatment applications. The fascinating properties of UiO-66 such as high thermal stability, superior chemical resistance towards several solvents, including benzene, acetone, different alcohols, dimethylformamide, acidic and...
A single–step synthesized supehydrophobic melamine formaldehyde foam for trace determination of volatile organic pollutants
, Article Journal of Chromatography A ; Volume 1525 , 2017 , Pages 10-16 ; 00219673 (ISSN) ; Zeinali, S ; Baktash, M. Y ; Sharif University of Technology
Abstract
Superhydrophobic materials have attracted many attentions in recent years while their application in sample preparation remained almost intact. In this project, a rough surface of melamine formaldehyde foam was silanized by chemical deposition of trichloromethylsilane to form a highly porous and superhydrophobic material, presumably a suitable medium for extracting non–polar compounds such as benzene and its methyl derivatives. The prepared sorbent was packed in a needle for the headspace needle–trap microextraction of benzene, toluene, ethylbenzene and xylenes (BTEX). Major parameters associated with the extraction/desorption processes were considered for optimization. Under the optimized...
Implementing a superhydrophobic substrate in immersed solvent–supported microextraction as a novel strategy for determination of organic pollutants in water samples
, Article Ecotoxicology and Environmental Safety ; Volume 163 , 2018 , Pages 104-110 ; 01476513 (ISSN) ; Asem Yousefi, A ; Bagheri, H ; Sharif University of Technology
Academic Press
2018
Abstract
In this research, a new approach for extraction and determination of polycyclic aromatic hydrocarbons from sea and rain water samples was developed by implementing a superhydrophobic substrate and consuming the least amount of solvent. This version of solvent–supported microextraction enabled us to perform the procedure in the immersion mode with the slightest troubles arising from water leakage into the gas chromatography. The superhydrophobic property leads to the fixation of extracting solvent on the substrate surface during water sampling. To prepare a superhydrophobic substrate, a piece of melamine foam was coated by tannic acid and silica nanoparticles using methyltrimethoxysilane and...
Multiple interactive pollutants in water quality trading
, Article Environmental Management ; Volume 42, Issue 4 , 2008 , Pages 620-646 ; 0364152X (ISSN) ; Lence, B. J ; Shamsai, A ; Sharif University of Technology
2008
Abstract
Efficient environmental management calls for the consideration of multiple pollutants, for which two main types of transferable discharge permit (TDP) program have been described: separate permits that manage each pollutant individually in separate markets, with each permit based on the quantity of the pollutant or its environmental effects, and weighted-sum permits that aggregate several pollutants as a single commodity to be traded in a single market. In this paper, we perform a mathematical analysis of TDP programs for multiple pollutants that jointly affect the environment (i.e., interactive pollutants) and demonstrate the practicality of this approach for cost-efficient maintenance of...
Delafossite-alumina nanocomposite for enhanced catalytic wet peroxide oxidation of anionic pollutants
, Article Journal of Hazardous Materials ; Volume 417 , 2021 ; 03043894 (ISSN) ; Nouri, O ; Xie, Z ; Setayesh, S. R ; Wei, Z ; Sharif University of Technology
Elsevier B.V
2021
Abstract
Mass transfer efficiency and catalytic reactivity are the two major hurdles for heterogeneous catalytic wet peroxide oxidation (CWPO) technologies. To address these issues, nanocomposite CuFeO2/Al2O3 was synthesized and assessed as a novel catalyst for enhanced adsorption and oxidation of anionic pollutants (catechol and reactive red 195 (RR195)) in waters. With a positive charge on the nanocomposite by introducing Al2O3, the adsorption of anionic pollutants was promoted. The surface complexation reaction on CuFeO2/Al2O3, which fits well to the Langmuir isotherm, has engined the mass transfer of pollutants to the nanocatalyst that demonstrated 96.46% and 99.75% removal of catechol and RR195...
Study and Assessment of Groundwater Vulnerability and Contamination to Nitrate: A Case Study of Mashhad City
, M.Sc. Thesis Sharif University of Technology ; Ataie-Ashtiani, Behzad (Supervisor)
Abstract
Groundwater resources in arid and semi-arid regions, which the most parts of them have not had enough surface water, is of great importance. Due to the paramount importance of these vital resources, many scholars have conducted various studies on groundwater contamination and, especially, on nitrate as the best indicator of groundwater contamination because of its ability to transport, its low absorption, and its durability in water. In this study, using qualitative methods, groundwater contamination of Mashhad aquifer was evaluated, and then in order to obtain better adjustment with urban areas, these methods were modified which resulted in better correlation with measured nitrat. Based on...