Loading...
Search for:
heavy-metal-removal
0.011 seconds
Feasibility Study of Using Nutshell Filters Enriched with Potassium Hydroxide for Chromium Removal
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Activated Carbon as a highly efficient and low price absorbent has manifold functions in separation and absorption processes in liquid or gas phases. These applications in liquid phase include bleaching in sugar syrup, water and wastewater treatment and in gas phase utilizing them in gas masks and solvent recycling process. Wide variety of base materials could be used to produce activated carbon. For instance rare cellulose materials -wood, coconut shell, Pyrenees and agricultural wastes-, carbon materials-coal, petroleum coke, tar- and polymer materials- tires and plastics wastes- could be mentioned. In this thesis, feasibility of producing activated carbon based on using walnut, almond...
Removal of Heavy Methal Ions from Wastwater Via Novel Nanocomposite of Biochar/Tio2
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Fathollah (Supervisor)
Abstract
To investigate the metallic cation (Ni and Pb) removal performance of the rice barn-obtained biochar which was modified by nitric acid and titanium nanoparticles (TiO2) adsorption tests were conducted in continuous and non-continuous systems. First section addressed the characterization of the synthesized sorbents using field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy dispersive X ray spectroscopy (EDX) and sorption-desorption porosity analysis (BET). In the second section, the effect of different parameters such as pH, initial concentration of the metallic ions, temperature, time, sorbent content, ionic...
Synthesis and Evaluation of Zeolitic Janus Micromotors for Water Remediation
, Ph.D. Dissertation Sharif University of Technology ; Madah Hosseini, Hamid Reza (Supervisor)
Abstract
Novel zeolite-based micromotors consisted of silver-exchanged zeolite core and three different partial catalytic coatings (Mg/Au, Pt and Ag) were synthesized to eliminate the biological and chemical contamination from water in a fast and efficient way. These engines are benefited by the adsorption capacity and antibacterial activity of silver-zeolites in combination with the autonomous propulsion of catalytic micromotors. The remarkable bactericidal capacity of these particles relies on reactive silver ion released from zeolite and accordingly, increased chance of contact with bacteria during movement. These motors showed rapid killing of bacteria and effective elimination of the Pseudomonas...
Investigation of Sulfate Reducing Bacteria for Treatment of Wastewaters Polluted by Heavy Metals
, M.Sc. Thesis Sharif University of Technology ; Kariminia Hamedani, Hamid Reza (Supervisor) ; Borghei, Mehdi (Supervisor)
Abstract
The main objective of this research was to evaluate the application of a new strain of Brevundimonas naejangsanensis which is newly identified sulfate-reducing bacteria (SRB), in chromium(VI) removal in contaminated wastewater. A laboratory scale packed bed reactor (PBR) was fabricated and operated to study the bacteria’s feasibility on chromium(VI) reduction and removal. The reactor was packed with polyurethane foam cubes and operated under different feeding and operating conditions of HRT, COD/〖SO〗_4^(2-) ratio and influent chromium(VI) concentration. A maximum chromium removal of 94.6% was achieved in the PBR when operated at an HRT of 24 h with COD/〖SO〗_4^(2-) ratio of .70 and influent...
Polymer matrix nanocomposites for heavy metal adsorption: a review
, Article Journal of the Iranian Chemical Society ; Volume 17, Issue 6 , 31 January , 2020 , Pages 1259-1281 ; Keikavousi Behbahan, A ; Sharif University of Technology
Springer
2020
Abstract
Heavy metals belong to a group of lethal environmental pollutants. Ongoing efforts targeted at safeguarding public health have led to considerable attention being focused on methods that allow efficient extraction of these toxic substances. Polymer nanocomposites (PNCs) with their special characteristics are a class of adsorbents that demonstrate high potential for use in heavy metal extraction. As this process of removal is predominantly governed by adsorption, various parameters in PNCs’ chemical structure, as well as the metal solutions, can have a significant effect on the adsorption process. Herein, this review undertakes a survey of recently developed PNCs and their metal adsorption...
Fast chromium removal by Shewanella sp.: an enzymatic mechanism depending on serine protease
, Article International Journal of Environmental Science and Technology ; Volume 17, Issue 1 , April , 2020 , Pages 143-152 ; Mahmoodi, R ; Mollania, N ; Kheirabadi, M ; Sharif University of Technology
Springer
2020
Abstract
Environmental pollutions with heavy metals pose serious health and ecological risks. Sabzevar in the northeast of Iran has natural chromic mines and then chromium-polluted soils and groundwater. In the present work, the metal-tolerant bacterial strain KR2 was identified as Shewanella sp. following 16S rDNA gene sequence analysis. Bioremediation ability of isolated bacterial from agricultural soils that irrigated by groundwater, Shewanella sp., was evaluated for uptaking of chromium with varying Cr(VI) concentrations from 50 to 500 ppm in aerobic conditions (pH 7.0, 37 °C). The Shewanella sp. strain KR2 showed an obvious heavy metal tolerant in the wide range of heavy metals including: Cr6+,...
Zwitterion-functionalized MIL-125-NH2-based thin-film nanocomposite forward osmosis membranes: towards improved performance for salt rejection and heavy metal removal
, Article New Journal of Chemistry ; Volume 46, Issue 31 , 2022 , Pages 15205-15218 ; 11440546 (ISSN) ; Bagherzadeh, M ; Navi, H ; Nikkhoo, M ; Amini, M ; Sharif University of Technology
Royal Society of Chemistry
2022
Abstract
In the current study, thin-film nanocomposite membranes (TFN-Mx) based on a zwitterion-functionalized metal-organic framework (MOF) have been developed for the forward osmosis (FO) salt-water separation process. The active polyamide layer was formed through the interfacial polymerization of the m-phenylenediamine aqueous phase (with or without the presence of MIL-125-NH-CC-Cys) and the trimesoyl chloride organic phase. In comparison with the results from the surface of the unmodified membrane, a nanofiller-incorporated TFN-M0.10 membrane represents a smoother and more wettable surface that collaborates synergically to enhance the membrane antifouling ability. Among the examined membranes,...
Heavy metal removal from water and wastewater using raw and modified diatomite
, Article International Journal of Engineering, Transactions B: Applications ; Volume 20, Issue 2 , 2007 , Pages 141-146 ; 1728-144X (ISSN) ; Nahid, P ; Sharif University of Technology
Materials and Energy Research Center
2007
Abstract
Heavy metal removal from water and wastewater was investigated by using raw and modified diatomite from Iranian mines. Modification of diatomite was done by impregnating the diatomite surface with 0.35 g of manganese oxide in one gram of diatomite. This modified diatomite was named Mn-Diatomite. The surface area measurements for Mn-diatomite showed a 2.2 fold increase, hence higher removal capacity for the heavy metals. The results of the removal showed an increase in adsorption capacity which was for Pb2+ about 40 mg/g, for Ni 2+ about 34mg/g and for Cu2+ about 33mg/g. The filtration quality of diatomite was significantly enhanced with surface modification by manganese oxide
Novel salep-based chelating hydrogel for heavy metal removal from aqueous solutions
, Article Polymers for Advanced Technologies ; Volume 27, Issue 8 , 2016 , Pages 999-1005 ; 10427147 (ISSN) ; Pourjavadi, A ; Monfared, A ; Khorasani, Z ; Sharif University of Technology
John Wiley and Sons Ltd
Abstract
A novel optimized chelating hydrogel was synthesized via graft copolymerization of acrylamide and 2-hydroxyethyl methacrylate (as two-dentate chelating co-monomer) onto salep (a multicomponent polysaccharide obtained from dried tubers of certain natural terrestrial orchids) using N,N′-methylenebisacrylamide as a crosslinker and ammonium persulfate as an initiator. Reaction parameters (N,N′-methylenebisacrylamide and ammonium persulfate amounts as well as acrylamide/2-hydroxyethyl methacrylate weight ratio) affecting the water absorption of the chelating hydrogel were optimized using a systematic method to achieve a hydrogel with high swelling capacity as possible. Heavy metal ion adsorption...
Photocatalytic removal of 2-nitrophenol using silver and sulfur co-doped TiO2 under natural solar light
, Article Water Science and Technology ; Volume 72, Issue 3 , 2015 , Pages 339-346 ; 02731223 (ISSN) ; Delparish, A ; Toufigh Bararpour, S ; Abedini Najafabadi, H ; Zakeri, S. M. E ; Vossoughi, M ; Sharif University of Technology
IWA Publishing
2015
Abstract
To overcome the drawback of poor solar light utilization brought about by the narrow photoresponse range of TiO2, a silver and sulfur co-doped TiO2 was synthesized. Using the prepared catalyst, solar photocatalytic degradation of 2-nitrophenol (2-NP) by a TiO2-based catalyst was studied for the first time. Effects of the co-doping on the structural, optical and morphological properties of the synthesized nanoparticles were investigated by different characterization methods: X-ray diffraction, N2 adsorption-desorption measurements, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, UV-visible diffuse reflectance spectroscopy and Fourier...
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,...
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,...
Application of chitosan-citric acid nanoparticles for removal of chromium (VI)
, Article International Journal of Biological Macromolecules ; Volume 80 , September , 2015 , Pages 431-444 ; 01418130 (ISSN) ; Younesi, H ; Hajati, S ; Borghei, S. M ; Sharif University of Technology
Elsevier
2015
Abstract
In the present study, CS-CA nanoparticle was prepared for forming a new amide linkage, by grafting the amino groups of CS in the presence of carboxylic groups of CA that acts as cross-linking agent. The as-prepared CS-CA nanoparticle samples were characterized by use of dynamic light scattering (DLS), scanning electron microscopy (SEM), Fourier-transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques, which showed that the cross-linking agent preserved during the chemical modifications. The adsorption capacity of the CS-CA nanoparticles for the removal of Cr (VI) in aqueous solution was studied. The adsorption equilibrium data...
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...
Comments on the " A comparative study of chelating and cationic ion exchange resins for the removal of palladium (II) complexes from acidic chloride media"
, Article Journal of Hazardous Materials ; Volume 229-230 , 2012 , Pages 461-462 ; 03043894 (ISSN) ; Khanchi, A. R ; Outokesh, M ; Tayebi, A ; Sharif University of TechnologyRemoval of chromium from aqueous solution using polyaniline - Poly ethylene glycol composite
, Article Journal of Hazardous Materials ; Volume 184, Issue 1-3 , December , 2010 , Pages 248-254 ; 03043894 (ISSN) ; Borghei, S. M ; Olad, A ; Chaichi, M. J ; Sharif University of Technology
2010
Abstract
The adsorption of chromium compounds from solutions by a composite of polyaniline/poly ethylene glycol (PANi/PEG) was investigated in this study. Experiments were conducted in batch mode under various operational conditions including agitation time, solution pH, PANi/PEG dose and initial concentration of chromium salts. Results showed that concentration of PEG at synthesizing stage has a significant effect on the capacity of produced composite for removal of chromium. Morphologically, PANi/PEG composite is closely dependent on the concentration of PEG. Maximum removal of hexavalent chromium was experienced when 2. g/L of PEG was used in synthesis of PANi/PEG. Removal of hexavalent chromium...
Synthesis of zero-valent iron nanoparticles via electrical wire explosion for efficient removal of heavy metals
, Article Clean - Soil, Air, Water ; Volume 45, Issue 3 , 2017 ; 18630650 (ISSN) ; Rabiee, H ; Seyed Shahabadi, S. M ; Borghei, S. M ; Sharif University of Technology
Abstract
In this paper, electrical wire explosion (EWE) was used as a simple, clean, in situ method to synthesise nano zero-valent iron (nZVI) particles in liquid mediums. The structural and physical properties of the synthesised nZVI particles were characterised by x-ray diffraction, Brunauer–Emmett–Teller analysis, field emission scanning electron microscopy and transmission electron microscopy. The synthesised spherical nanoparticles, at a specific size of 10–50 nm, possessed large surface areas of approximately 13.27 m2/g, reinforcing the significant advantages of EWE, that is, less aggregation and in situ production of nanoparticles with enhanced removal efficacy, for groundwater treatment....