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adsorption-kinetics
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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...
Investigation of Asphaltene Electro-deposition Under Dynamic Flow Conditions
, M.Sc. Thesis Sharif University of Technology ; Taghikhani, Vahid (Supervisor) ; Ayatollahi, Shahabodin (Supervisor)
Abstract
Asphaltene, known as the heaviest and the most polar component of the crude oil, can precipitate because of the changes in the fluid condition such as pressure, temperature and composition. Asphaltene deposition causes major problems during oil production, in the form of fluid viscosity changes, wellbore damage and fouling in pipelines. The remediation of these problems is very expensive and needs to halt down the crude oil production. The use of electric field has been proposed recently as clean and cheap technique that could also be applied during the production period. In this work, the effect of electric potential on asphaltene precipitation in both static and dynamic modes has been...
Synthesis, Evaluation and Modification of Suitable Metal–Organic Frameworks (MOFS) for Desulfurization of Hydrocarbon Cuts
, M.Sc. Thesis Sharif University of Technology ; Khorashe, Farhad (Supervisor) ; Hajjar, Zeinab (Co-Supervisor) ; Soltanali, Saeed (Co-Supervisor)
Abstract
During fuel combustion, aromatic sulfur compounds in energy fuels convert into sulfur oxides, which cause major environmental problems such as acidic rain, global warming, and air pollution. Absorption desulfurization is one of the promising and economical methods to remove these sulfur compounds from fuels. Metal-organic frameworks (MOFs) are a class of nanoporous materials that are of interest for use as adsorbents due to their high specific surface area, unique surface adsorption properties, high adsorption capacity, tunable porosity, flexible dynamic behavior, and diversity in functional and metal groups. In this research, we first synthesized five metal-organic frameworks, namely...
Kinetics and Mechanism Study of Chemical Pollutant Adsorption Using Organic Ligands Modified Nano-adsorbents
, M.Sc. Thesis Sharif University of Technology ; Golami, Mohammad Reza (Supervisor)
Abstract
Among various methods for purifying water from dyes, adsorption takes advantage of simplicity, high efficiency, no secondary-pollution, and inexpensiveness. In this project Halloysite nanoparticles were applied to prepare a series of modified polyAcrylamide- quince seed gum hydrogels (QS/PAAm/Haln). The obtained hydrogels demonstrated improved efficiency as adsorbent in removing methylene blue (MB) from aqueous media. The structure of the prepared hydrogel nanocomposites were identified by X-ray diffraction, Brunauer-Emmett-Teller surface area analysis, Fourier-transform infrared spectroscopy, scanning electron microscope and energy-dispersive X-ray spectroscopy. Kinetics, thermodynamic,...
Experimental Investigation of Heavy Oil Recovery by Natural Surfactant Injection in Heterogeneous Systems Using Micromodel Apparatus
, M.Sc. Thesis Sharif University of Technology ; Rashtchian, Davood (Supervisor) ; Ghazanfari, Mohammad Hossein (Co-Advisor)
Abstract
Nowadays, due to limitation of production from conventional oil reservoirs, enhanced recovery from heavy oil reservoirs is of great concern. However, production from these energy resources is not a simple task and production using common technologies is not easily exploitable. Heterogeneous structure and also high surface tension between injected fluid and reservoir oil are of the main challenges during water flooding processes in heavy oil reservoirs. The high surface tension force causes a large part of the oil remains in the reservoir after the water flooding operation. One method for overcoming this problem is the use of surfactants that reduces capillary forces and consequently...
Synthesis of Graphene by New Methods, and its Application for Adsorption of Cobalt
, M.Sc. Thesis Sharif University of Technology ; Outokesh, Mohammad (Supervisor) ; Shafiekhani, Azizollah (Supervisor)
Abstract
In this study graphene and graphene adsorbent for the Co2+ ion were created from sodium phenoxide and calcium phenoxide, respectively, using the chemical vapor deposition method, and their chemical, physical, and morphological properties were investigated using FT-IR, UV, XRD, Raman, TEM, FE-SEM, and XPS. The results suggest that the optimum reaction condition for synthesizing mono-layer and multi-layer graphene is the 750 °C temperature for 30 min. The Co2+ adsorbing properties of the synthesized graphene adsorbent from calcium phenoxide was investigated. The investigation of solvation properties suggests insolubility above 650 °C and the kinetic data suggest the rapidness of the Co2+...
Kinetics of oxygen adsorption on ZnS nanoparticles synthesized by precipitation process
, Article Materials Science- Poland ; Volume 34, Issue 2 , 2016 , Pages 260-265 ; 20831331 (ISSN) ; Sadrnezhad, S. K ; Namivandi Zangeneh, R ; Oghabian, M. A ; Sharif University of Technology
Walter de Gruyter GmbH
Abstract
ZnS nanoparticles were synthesized through a one-step precipitation process. Effect of time and temperature on the formation reaction was investigated. The synthesized samples were characterized by X-ray diffraction (XRD), ultraviolet (UV) visible absorption and photoluminescence (PL) spectrophotometry. Based on XRD and UV-Vis data, the particles produced at 70 °C had a mean particle size of about 5 nm. Increasing time and temperature of the synthesis reaction resulted in photoluminescence intensification. PL spectroscopy helped understanding the adsorption kinetics of oxygen on ZnS nanoparticles during the precipitation synthesis process. Fabrication of ZnS structures with appropriate...
Preparation and evaluation of hydrogel composites based on starch-g-PNaMA/eggshell particles as dye biosorbent
, Article Desalination and Water Treatment ; Volume 57, Issue 39 , 2016 , Pages 18144-18156 ; 19443994 (ISSN) ; Darvishi, A ; Sharif University of Technology
Taylor and Francis Inc
Abstract
In this study, eggshell (ES) particles as an available and low-cost waste material were used for preparing hydrogel composites as dye biosorbents. For this purpose, hydrogel composites were prepared through free-radical graft copolymerization of wheat starch and sodium methacrylate (NaMA) in the presence of different contents of ES particles with various size ranges. FTIR spectroscopy confirmed graft copolymerization of NaMA moieties onto starch backbone besides the combination of ES particles with the starch-g-PNaMA matrix. The gel content values were high (>99%), which showed proper graft efficiency for hydrogel composites. Incorporation of ES particles into hydrogel matrix resulted in...
Spotlight on kinetic and equilibrium adsorption of a new surfactant onto sandstone minerals: A comparative study
, Article Journal of the Taiwan Institute of Chemical Engineers ; Volume 50 , May , 2015 , Pages 12-23 ; 18761070 (ISSN) ; Ghazanfari, M. H ; Rashtchian, D ; Sharif University of Technology
Taiwan Institute of Chemical Engineers
2015
Abstract
This paper presents a state of the art review of adsorption models for a new plant-based surfactant adsorption onto sandstone minerals. The adsorption data at both kinetic and equilibrium modes were obtained from batch experiments. Four adsorption kinetic models, five two-parameter, and six three-parameter equilibrium models were used for interpretation of the obtained data. Among the two and three-parameter isotherm models applied, the Jovanovic and the Khan isotherms showed the best fit, respectively. And the pseudo-second order model presented a better fit than other kinetic models. Finally, a computer-based modeling approach was developed and used for predicting the kinetics of...
Mechanistic evaluation of cationic dyes adsorption onto low-cost calcinated aerated autoclaved concrete wastes
, Article International Journal of Environmental Science and Technology ; Volume 19, Issue 7 , 2022 , Pages 6429-6444 ; 17351472 (ISSN) ; Eftekhari, M ; Tabrizi, M. G ; Fathollahi Fard, A. M ; Tian, G ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2022
Abstract
Application of construction and demolition (C&D) wastes were considered as sustainable development goals (SDGs) for maintaining raw materials. Also, lightweight concretes such as aerated autoclaved concrete (AAC) were used for partitioning spaces in the building industry. Moreover, the waste products of the mentioned materials were increased due to the rise of old construction demolitions. This study contributes a calcinated aerated autoclaved concrete (CAAC) which is efficient, powerful, highly rapid, non-expensive and novel adsorbent for the removal of cationic dyes including malachite green (MG), methyl violet (MV) and methylene blue (MB) form water samples. The impacts of different...
Cooperation within von Willebrand factors enhances adsorption mechanism
, Article Journal of the Royal Society Interface ; Volume 12, Issue 109 , 2015 ; 17425689 (ISSN) ; Mehrbod, M ; Ejtehadi, M. R ; Mofrad, M. R ; Sharif University of Technology
Royal Society of London
2015
Abstract
von Willebrand factor (VWF) is a naturally collapsed protein that participates in primary haemostasis and coagulation events. The clotting process is triggered by the adsorption and conformational changes of the plasma VWFs localized to the collagen fibres found near the site of injury. We develop coarse-grained models to simulate the adsorption dynamics of VWF flowing near the adhesive collagen fibres at different shear rates and investigate the effect of factors such as interaction and cooperativity of VWFs on the success of adsorption events. The adsorption probability of a flowing VWF confined to the receptor field is enhanced when it encounters an adhered VWF in proximity to the...
Removal of methylene blue dye from aqueous solutions using carboxymethyl-β-Cyclodextrin-Fe3O4 nanocomposite: Thermodynamics and kinetics of adsorption process
, Article Russian Journal of Physical Chemistry A ; Volume 96, Issue 2 , 2022 , Pages 371-380 ; 00360244 (ISSN) ; Aghaie, H ; Monajjemi, M ; Gholami, M. R ; Sharif University of Technology
Pleiades journals
2022
Abstract
Abstract: The applicability of the synthesized carboxymethyl-β-cyclodextrin-Fe3O4 nanocomposite (CM‑β-CD-Fe3O4NPs) as a novel adsorbent for eliminating Methylene blue dye (MB) from aqueous media was investigated. Various techniques including Brunauer Emmett Teller analysis (BET), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) have been used to characterize this novel adsorbent. The effect of initial concentration (C0), pH, adsorbent dosage (dose), contact time (tc), and temperature (T, K) on the removal percentage (Ad%) of MB dye onto CM-β-CD-Fe3O4NPs was studied, and the optimum value...
Synthesis and application of diethanolamine-functionalized polystyrene as a new sorbent for the removal of p-toluenesulfonic acid from aqueous solution
, Article Journal of Industrial and Engineering Chemistry ; Volume 30 , October , 2015 , Pages 281-288 ; 1226086X (ISSN) ; Ahmadpour, A ; Rohani Bastami, T ; Dabir, H ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2015
Abstract
Polystyrene resin was functionalized by diethanolamine for the efficient removal of p-toluenesulfonic acid (p-TSA) from aqueous solution. Functionalized adsorbent (DEA-PS) was characterized by elemental analysis, Fourier transform infrared spectroscopy, point of zero charge measurement and field-emission scanning electron microscopy. According to the results, maximum removal of p-TSA was observed at the pH range of 2.5-5. The adsorption kinetics of p-TSA onto DEA-PS was represented by pseudo-first-order model and the equilibrium data followed Langmuir model well. The adsorption process was endothermic and spontaneous, along with the positive change of entropy. The regeneration of DEA-PS was...
Kinetics and adsorptive study of organic dye removal using water-stable nanoscale metal organic frameworks
, Article Materials Chemistry and Physics ; Volume 233 , 2019 , Pages 267-275 ; 02540584 (ISSN) ; Simchi, A ; Shahriyari Far, H ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Kinetics and isotherms of adsorption behavior of nanoscale Zr-based metal-organic framework for the removal of three organic dyes including acidic, direct and basic ones from aqueous solutions were studied by sorption models. Nanocube-shaped UiO-66 particles with an average edge length of 215 nm, specific surface area of 1215 m2/g, total pore volume of 0.58 cm3/g, and average pore diameter of 1.8 nm were prepared by solvothermal methods. Analyzing of the equilibrium isotherms indicates that direct dye removal is best fitted with the Langmuir isotherm. Study of the adsorption kinetics also determines that direct dye adsorption follows pseudo-first-order model (R2=0.99). The kinetics of basic...
Ultrafast and simultaneous removal of anionic and cationic dyes by nanodiamond/UiO-66 hybrid nanocomposite
, Article Chemosphere ; Volume 247 , May , 2020 ; Neshastehgar, M ; Shojaei, A ; Ghashghaeinejad, H ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this research, UiO-66 and its composite nanoparticles with thermally oxidized nanodiamond (OND) were synthesized via a simple solvothermal method and utilized as solid adsorbent for the removal of anionic methyl red (MR) dye and cationic malachite green (MG) dye from contaminated water. The synthesized adsorbents were analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), N2 adsorption–desorption, and zeta potential analyzer. The influences of various factors such as initial concentrations of the dyes, adsorption process time, solution pH, solution temperature and ionic...
Spinel H4Ti5O12 nanotubes for Li recovery from aqueous solutions: Thermodynamics and kinetics study
, Article Journal of Environmental Chemical Engineering ; 2020 ; Shahnaz, G ; Askari, M ; Khosravi, A ; Hasan Zadeh, A ; Alamolhoda, A. A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
In this study, H4Ti5O12 nanotubes have been prepared as Li+ adsorbent by acid treatment of Li4Ti5O12 nanotubes. Li4Ti5O12 nanotubes were synthesized via a hydrothermal method in which TiO2(B) nanNotubes were used as a precursor. The prepared Li-ion sieve showed a significant high ion-exchange capacity (160.6 mgg-1) for lithium ions due to its large specific surface area of 115.4 m2 g-1 compared to the other related studies. The kinetics and isotherm investigation revealed that the pseudo-second-order equation well described the adsorption kinetics, and the Langmuir model well fitted the isotherm data. Furthermore, the low value of adsorption energy obtained from the Dubinin-Radushkevitch...
Removal of Cu (ll) from industrial wastewater using poly (acrylamide-co-2-acrylamide-2-methyl propane sulfonic acid)/graphene oxide/sodium alginate hydrogel: Isotherm, kinetics, and optimization study
, Article Journal of Water Process Engineering ; Volume 42 , 2021 ; 22147144 (ISSN) ; Ghasemi, S ; Khosravi, A ; ZabihiSahebi, A ; Hasan Zadeh, A ; Borghei, S. M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Here, Graphene oxide/poly (acrylamide -2-acrylamide-methyl-propanesulfonic acid)/sodium alginate (GO/PA-AMPS/SA) hydrogel was synthesized through a free-radical polymerization approach. The impact of Graphene Oxide (GO) content on mechanical strength, swelling behavior, and the adsorption performance of prepared hydrogel was studied. The operating parameters, including contact time, solution pH, and initial Cu(II) content on the adsorption capacity of the hydrogel, were studied. The maximum Cu(II) adsorption capacity of 230.8 mg/g was obtained for GO/PA-AMPS/SA under a pH of 5, the contact time of 270 min, and adsorbent content of 0.5 g/L at 25 °C. The high value of adsorption capacity after...
Spinel H4Ti5O12 nanotubes for Li recovery from aqueous solutions: Thermodynamics and kinetics study
, Article Journal of Environmental Chemical Engineering ; Volume 9, Issue 1 , 2021 ; 22133437 (ISSN) ; Ghasemi, S ; Askari, M ; Khosravi, A ; Hasan Zadeh, A ; Alamolhoda, A. A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
In this study, H4Ti5O12 nanotubes have been prepared as Li+ adsorbent by acid treatment of Li4Ti5O12 nanotubes. Li4Ti5O12 nanotubes were synthesized via a hydrothermal method in which TiO2(B) nanNotubes were used as a precursor. The prepared Li-ion sieve showed a significant high ion-exchange capacity (160.6 mgg−1) for lithium ions due to its large specific surface area of 115.4 m2 g-1 compared to the other related studies. The kinetics and isotherm investigation revealed that the pseudo-second-order equation well described the adsorption kinetics, and the Langmuir model well fitted the isotherm data. Furthermore, the low value of adsorption energy obtained from the Dubinin-Radushkevitch...
Fe3O4@PAA@UiO-66-NH2 magnetic nanocomposite for selective adsorption of Quercetin
, Article Chemosphere ; Volume 275 , 2021 ; 00456535 (ISSN) ; Tajahmadi, S ; Haris, M. H ; Bahi, A ; Rezakazemi, M ; Molavi, H ; Ko, F ; Arjmand, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
In the present study, a magnetic core-shell metal-organic framework (Fe3O4@PAA@UiO-66-NH2) nanocomposite was synthesized by a facile step-by-step self-assembly technique and used for selective adsorption of the anti-cancer Quercetin (QCT) drug. The synthesized nanocomposite was well characterized using FTIR, XRD, BET, FESEM, and TEM techniques. The adsorption kinetics and isotherms of the magnetic nanocomposites for QCT were investigated in detail at different initial concentrations and temperatures. It was found that the experimental adsorption kinetic and isotherm data were precisely explained by the pseudo-second-order kinetic and Langmuir isotherm models. Moreover, the selective...
Ethylenediamine-functionalized Zr-based MOF for efficient removal of heavy metal ions from water
, Article Chemosphere ; Volume 264 , 2021 ; 00456535 (ISSN) ; Tajahmadi, S ; Bahi, A ; Molavi, H ; Rezakazemi, M ; Ko, F ; Aminabhavi, T. M ; Arjmand, M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Ethylenediamine-functionalized Zr-based metal-organic framework (MOF, UiO-66-EDA) was prepared via Michael addition reaction to investigate its potential for adsorption of heavy metal ions from water. Specifically, the influence of agitation time, solution pH, the dosage of the adsorbent, initial metal ion concentration, temperature, and coexistence of other metal ions was investigated on the removal efficiency of UiO-66-EDA towards Pb(II), Cd(II), and Cu(II) metal ions. The pseudo-second-order kinetic model governed the adsorption of these ions onto the UiO-66-EDA. Langmuir isotherm model matched the experimental isotherm of adsorption with a maximum adsorption capacity of 243.90, 217.39,...