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larimi--afsanehsadat
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Production of Biodiesel Using Calcite Stone as Support Catalyst
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsanehsadat (Supervisor)
Abstract
The aim of this study is developing and investigating heterogeneous catalysts based on natural calcite for the transesterification of canola oil and methanol in order to produce biodiesel as a renewable and alternative fuel for fossil fuels. At first calcite was calcined at high temperature to decompose calcium carbonate to calcium oxide. Afterward, Mg-Zr/CaO catalysts were prepared with mass ratio of 2:1 Mg:Zr and different weight percent(2.5, 5,7.5 and 10 wt%) on calcite supported by impregnation method. In order to characterized synthesized catalysts used different analysis such as energy dispersive X-ray (EDX) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy...
Photocatalytic Conversion of CO2 under Visible Light Irradiation
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Hamzehlouyan,Tayebeh (Supervisor) ; Larimi, Afsanehsadat (Supervisor)
Abstract
The photoreduction of CO2 to produce renewable solar fuel known as artificial photosynthesis attracted a lot of attention during the last two decades due to the global warming issue caused through increasing CO2 and shortage of fossil fuels resources. In this study, in order to enhance photocatalytic process of CO2 under visible light, TiO2-graphene and TiO2-copper nanocomposite utilized. A series of Cu/TiO2 photocatalysts were prepared with various Cu (2, 5 and 8 wt%) and a series of G/TiO2 photocatalysts with different graphene (G) content (5, 20 and 40 wt.%) were prepared and tested for the reduction of CO2. XRD, BET, DRS and TEM analyses employed to characterize the catalyst while the...
Fabrication of Nanostructured Electrocatalysts For Use in Water Splitting Process
, M.Sc. Thesis Sharif University of Technology ; Kharaseh, Farhad (Supervisor) ; Asgharinejhad, Ali Akbar (Supervisor) ; Larimi, Afsanehsadat (Co-Supervisor)
Abstract
In this study, nanostructured electrocatalysts based on Ni–Cu–Co trimetallic metal–organic framework (MOF) were synthesized with trimesic acid ligand (H3BTC) and modified with graphene oxide (GO) and selenium (Se) to improve the performance in resistance reactions (OER). Ni.Cu.Co.MOF, Ni.Cu.Co.MOF/GO, Ni.Cu.Co.Se and Ni.Cu.Co.MOF/GO.Se samples were prepared by sol-thermal method and post-synthesis processes. Structural and morphological investigations were carried out using X-ray diffraction (XRD), fast transformation infrared (FTIR), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray (EDX) analysis along with elemental mapping. XRD and FTIR...
Renewable hydrogen production by ethylene glycol steam reforming over Al2O3 supported Ni-Pt bimetallic nano-catalysts
, Article Renewable Energy ; Volume 128 , 2018 , Pages 188-199 ; 09601481 (ISSN) ; Khorasheh, F ; Sharif University of Technology
2018
Abstract
The steam reforming of ethylene glycol, a simple model compound for biomass-derived liquids, is considered to be an environmentally green process for producing renewable hydrogen. Both Pt and Ni species are known for their catalytic activity under steam reforming reaction conditions. In this investigation, alumina supported Ni-Pt bimetallic catalysts (X wt% Ni-Y wt% Pt/Al2O3 named XNi-YPt) were employed for steam reforming of ethylene glycol. The prepared catalysts were characterized by XRD, BET, H2-TPR, H₂-Chemisorption, and TEM. It was observed that Ni/Pt ratio strongly affected the redox behavior, BET surface area, and particle size of the samples that in turn affected their catalytic...
Renewable hydrogen production over Pt/Al₂O₃ nano-catalysts: Effect of M-promoting (M=Pd, Rh, Re, Ru, Ir, Cr)
, Article International Journal of Hydrogen Energy ; Volume 44, Issue 16 , 2019 , Pages 8243-8251 ; 03603199 (ISSN) ; Khorasheh, F ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Xwt% Pt/Al 2 O 3 (X = 1, 3, 5, 8, 10) and 5 wt% Pt-1wt% M/AlO 3 (M = Pd, Rh, Re, Ru, Ir, Cr) catalysts were prepared, characterized and tested for aqueous phase reforming of pure and crude glycerol. Results show drastic dependence of catalytic performance of catalysts on both the active metal loading and the type of applied promoters. 5 wt% was the best Pt loading and Pt[sbnd]Rh/Al₂O₃ shows the best catalytic activity which has the highest hydrogen production rate (mmol/g cat h −1 ) and selectivity (89%) in continuous aqueous phase reforming of 10 wt% pure glycerol solution
Carbonaceous supports decorated with Pt–TiO2 nanoparticles using electrostatic self-assembly method as a highly visible-light active photocatalyst for CO2 photoreduction
, Article Renewable Energy ; Volume 145 , January , 2020 , Pages 1862-1869 ; Khorasheh, F ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Supported Pt–TiO₂ photocatalysts on carbonaceous supports were synthesized by the electrostatic self-assembly method to study CO₂ photoreduction to produce CH₄. Catalytic activities of the prepared photocatalysts were correlated with the particle size and dispersion of the active metal, which in turn depended on the type of carbonaceous support used, varying in the order of multi-walled carbon nanotubes (MWCNT) > Single-walled carbon nanotubes (SWCNT) > reduced graphene oxide > activated carbon. Generally, all catalysts were highly photoresistant with less than 5% loss of activity in terms of CH₄ yield. Pt–TiO₂/multi-walled carbon nanotubes exhibited better catalytic activity compared with...
Developing a mathematical model for reforming of glycerol towards a comparative evaluation of the liquid vs. gas phase medium
, Article International Journal of Hydrogen Energy ; Volume 44, Issue 49 , 2019 , Pages 26764-26772 ; 03603199 (ISSN) ; Kazemeini, M ; Larimi, A ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Glycerol might be converted into hydrogen through a catalytic reforming process. In order to design an effective route, the choice of reaction conditions and in particular its medium considered yet a crucial issue still needing further investigations. In this research, a mathematical model of reforming processes in vapor (i.e., steam reforming (SR) and liquid phase (i.e.; aqueous phase reforming (APR)) were developed. This was performed in terms of understudying effects of parameters including the reactor diameter, catalyst morphology (i.e., particle size) and mass flow rate on the glycerol conversion. Then, a superior reaction medium in terms of these variables was determined. For data...
Pt nanoparticles decorated Bi-doped TiO2 as an efficient photocatalyst for CO2 photo-reduction into CH4
, Article Solar Energy ; Volume 211 , 15 November , 2020 , Pages 100-110 ; Khorasheh, F ; Larimi, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Pt@Bi-TiO2 photocatalysts with different Bi (0–5 wt%) and Pt (0–2 wt%) contents were prepared by a two-step sol-gel and photo-deposition technique and were used in photo-reduction of CO2. The synthesized catalysts were characterized by X-ray powder diffraction (XRD), UV–Vis diffuse reflectance spectroscopy (DRS), scanning and transmission electron microscopy (SEM and TEM), nitrogen sorption measurement (BET), Raman spectroscopy, Electron paramagnetic resonance (EPR) spectroscopy and photoluminescence spectroscopy (PL). CO2 photo-reduction results revealed that the introduction of Bi into TiO2 structure and subsequent loading of Pt on its surface significantly increased the methane yield....
Biodiesel production via transesterification of canola oil in the presence of Na–K doped CaO derived from calcined eggshell
, Article Renewable Energy ; Volume 163 , 2021 , Pages 1626-1636 ; 09601481 (ISSN) ; Khorasheh, F ; Larimi, A ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
CaO derived from calcined eggshell was doped with Na–K by wet impregnation method and the effect of different Na/K molar ratios was investigated on biodiesel production from canola oil. The catalysts were characterized by X-ray Powder Diffraction (XRD), Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), and Thermogravimetric (TGA) analyses. FAME yields were determined by Gas Chromatography-Mass Spectrometry (GC-MS). The Na–K/CaO catalyst with Na/K molar ratio of 1 showed the highest FAME yield of 97.6% at optimum reaction conditions. Structural investigation of materials revealed that FAME yield was proportional to the number of basic sites on...
Fabrication of nano-dandelion magnetic TiO2/CuFe2O4 doped with silver as a highly visible-light-responsive photocatalyst for degradation of Naproxen and Rhodamine B
, Article Journal of Molecular Liquids ; Volume 407 , 2024 ; 01677322 (ISSN) ; Khorasheh, F ; Larimi, A ; Sharif University of Technology
2024
Abstract
Nano-dandelion TiO2 and magnetic CuFe2O4 were synthesized with hydrothermal and sol–gel processes, respectively. A series of composites containing different amounts of CuFe2O4 and Ag were also prepared using a photoreduction method. The composites were subsequently used for photodegradation of Naproxen and Rhodamine B under UV–Vis light irradiation. The synthesized photocatalysts were characterized by XRD, FTIR, FESEM, EDX, TEM, BET-BJH, DRS, and PL analyses. XRD and FESEM results confirmed the successful synthesis of the dandelion structure for the composites. The VSM analysis also demonstrated the enhancement of magnetic properties of composites. DRS results indicated that CuFe2O4 loading...
Aqueous phase reforming of glycerol using highly active and stable Pt0.05CexZr0.95-xO2 ternary solid solution catalysts
, Article Applied Catalysis A: General ; Volume 523 , 2016 , Pages 230-240 ; 0926860X (ISSN) ; Kazemeini, M ; Khorasheh, F ; Sharif University of Technology
Elsevier
2016
Abstract
The aqueous phase reforming (APR) of glycerol is an attractive yet challenging pathway to convert abundant biomass into value added hydrogen. Pt catalysts have received attention due to their ability to produce hydrogen-rich gas under APR conditions. In this work, the conversion of glycerol into hydrogen is demonstrated using Pt0.05CexZr0.95-xO2 (x = 0, 0.29, 0.475, 0.66 and 0.95) solid solution catalysts. Both characteristic (XRD, BET, H2-TPR, CO-chemisorption, TEM and XPS) and reactivity measurements were used to investigate the activity of the catalysts. Results indicated that reactivity depended on the Ce/Zr ratio, which in turn affected the Pt oxidation state, active metal dispersion...
Highly selective doped Pt[sbnd]MgO nano-sheets for renewable hydrogen production from APR of glycerol
, Article International Journal of Hydrogen Energy ; Volume 41, Issue 39 , 2016 , Pages 17390-17398 ; 03603199 (ISSN) ; Kazemeini, M ; Khorasheh, F ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
A series of M-doped Pt[sbnd]MgO (M = Pd, Ir, Re, Ru, Rh and Cr) sheet-shaped nano-catalysts were synthesized by the controlled co-precipitation method. The effects of M-doping on both the physicochemical and the chemisorption characteristics of Pt[sbnd]MgO catalysts were examined. The performance of the catalysts for the aqueous phase reforming (APR) of glycerol was also investigated. The APR activity of Pt[sbnd]M[sbnd]MgO catalysts depended on the type of the M dopant used. The APR activity varied in the following order: Rh > Pd > Cr > Ir > undoped ≈ Ru > Re, with the Rh-promoted catalyst having an activity of about one order of magnitude higher than the Re-promoted catalyst at 250 °C. It...
Aqueous-phase reforming of glycerol for production of alkanes over Ni/CexZr1-xO2 nano-catalyst: Effects of the support's composition
, Article Renewable Energy ; Volume 108 , 2017 , Pages 417-424 ; 09601481 (ISSN) ; Kazemeini, M ; Larimi, A. S ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
The aqueous phase reforming (APR) reaction of glycerol considered to be environmentally green. It converted polyols into value added products including; H2 and alkanes. Ni species known for its capability of producing alkane-rich gas under the APR process conditions might be utilized for this purpose. In this research, the conversion of glycerol into alkanes demonstrated using 10wt% Ni/CexZr1-xO2 (with x = 0, 0.3, 0.5, 0.7 and 1) catalysts. In order to better understand the behavior of these materials, they were evaluated physio-chemically through the; XRD, BET, H2-TPR, H2-Chemisorption and TEM analyses. Moreover; performances of the synthesized materials were determined through their...
Ultra-deep photocatalytic oxidative desulfurization of liquid fuels by Ti@CeO2/ZnO nanophotocatalyst under visible light and mild operating conditions
, Article Journal of Industrial and Engineering Chemistry ; Volume 134 , 2024 , Pages 548-560 ; 1226086X (ISSN) ; Asgharinezhad, A. A ; Larimi, A ; Sharif University of Technology
2024
Abstract
Herein, various Ti@CeO2/ZnO nanophotocatalysts (TxCZ, x: the molar ratio of Ti to Ce and Zn) were synthesized using the solvothermal method in two stages. After that, the effectiveness of the fabricated catalysts in the photocatalytic oxidative desulfurization (PODS) reaction were assessed. The physicochemical properties of the synthesized samples were analyzed through the implementation of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), ultraviolet–visible diffuse reflectance spectroscopy (UV–Vis DRS), photoluminescence...
Production of renewable hydrogen through aqueous-phase reforming of glycerol over Ni/Al2O3–MgO nano-catalyst
, Article International Journal of Hydrogen Energy ; Volume 43, Issue 2 , 2018 , Pages 614-621 ; 03603199 (ISSN) ; Kazemeini, M ; Larimi, A ; Maleki, H ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
In this study, a series of Ni nano-catalysts supported on Al2O3 and MgO were prepared through the co-precipitation technique. Effects of the Al/Mg ratio on physicochemical characteristics of Ni/Al2O3–MgO catalysts were examined. Moreover, catalytic performance was investigated in order to determine the optimum catalyst for H2 production in aqueous phase reforming (APR) of glycerol. It was revealed that, the APR activity of synthesized catalysts strongly depended on the aforementioned ratio. In addition, it was observed that, the catalytic activity of Ni/MgO and Ni/Al2O3 samples were both lower than that of the corresponding mixed oxide supports. Furthermore, it was shown that, amongst the...
Ni-Bi co-doped TiO2 as highly visible light response nano-photocatalyst for CO2 photo-reduction in a batch photo-reactor
, Article Journal of CO2 Utilization ; Volume 41 , October , 2020 ; Ghotbi, C ; Khorasheh, F ; Larimi, A ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Photocatalytic reduction of CO2 is considered as a promising strategy for production of a wide range of renewable hydrocarbon fuels by solar energy. In this investigation, a series of Ni and Bi doped TiO2 catalysts with different Ni and Bi contents were synthesized by the conventional sol-gel method and tested for CO2 photoreduction under visible light irradiation. Synthesized nano-photo-catalysts were characterized by XRD, FESEM, TEM, DRS, PL, FTIR and BET analyses. BET results indicated that the doping of Ni or/and Bi in the TiO2 framework resulted in BET specific surface area increment with respect to pure TiO2. DRS analysis showed that Ni doped TiO2, Bi doped TiO2, and co-doped samples...
Multiphase modeling of powder flow in an ejector of solar-driven refrigeration system by eulerian-lagrangian approach
, Article Nanotechnology Applications for Solar Energy Systems ; 2023 , Pages 313-336 ; 978-111979123-2 (ISBN); 978-111979114-0 (ISBN) ; Najafi, A ; Larimi, M ; Parhizkari, M ; Sharif University of Technology
wiley
2023
Abstract
The ejectors are the type of vacuum or pressure-based pump widely applicable in power engineering, thermal systems, and new solar-driven refrigeration systems. Streams inside the ejectors are complex, and it is not easy to describe the best possible flows and design by considering different hydrothermal properties. Nowadays, nanofluids are considered as a method for increasing the heat transfer rate in heat pipes, heat exchangers, and different parts of solar-driven systems which these progress reported and categorized in literature. In this study, the design parameters and optimization of an ejector for a solar-based refrigeration system, for generation vacuum, and consequently, maximum...
Transesterification of canola oil and methanol by lithium impregnated CaO–La2O3 mixed oxide for biodiesel synthesis
, Article Journal of Industrial and Engineering Chemistry ; Volume 47 , 2017 , Pages 399-404 ; 1226086X (ISSN) ; Kazemeini, M ; Larimi, A. S ; Khorasheh, F ; Sharif University of Technology
2017
Abstract
CaO–La2O3 mixed oxides were synthesized by co-precipitation coupled with Li doping through wet impregnation. These were used as catalysts for transesterification of canola oil and methanol toward biodiesel production. To determine the structure and morphology of the prepared catalysts, they were characterized by the XRD, FESEM, BET, and basic strength measurements. Under optimum reaction conditions of methanol/oil molar ratio of 15:1, 5 wt% catalyst at 65 °C, 96.3% conversion was obtained in 2.5 h of reaction duration. Moreover, the catalyst demonstrated a rather high stability where reuse of up to five cycles without significant loss of performance observed. © 2016 The Korean Society of...
Highly efficient electrocatalytic water oxidation based on non-precious metal oxides/sulfides derived from a FeCoNi-metal organic framework
, Article Journal of Alloys and Compounds ; Volume 1002 , 2024 ; 09258388 (ISSN) ; Asgharinezhad, A. A ; Larimi, A ; Ghotbi, C ; Sharif University of Technology
2024
Abstract
One of the main challenges for oxygen evolution reaction (OER) is to develop electrocatalysts with high performance, suitable stability, and low cost. First-row transition metal compounds have received attention due to their high electrocatalytic activity and diverse electronic structure. Meanwhile, metal-organic frameworks (MOFs) have emerged as promising alternative for OER due to their porous structure and unsaturated metal sites. In this study, FeCoNi-MOF based on MIL-88B was synthesized by a hydrothermal method. Then, the performance of the catalyst was investigated and improved by calcination and sulfidation at three temperatures of 250 ℃, 350 ℃, and 450 ℃. The phase development and...
Production of Biodiesel Using Eggshell as Catalyst
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Larimi, Afsaneh Sadat (Supervisor)
Abstract
The aim of this project is to investigate and synthesize CaO-based nanocatalysts derived from chicken eggshell calcination with alkali metals and sodium-potassium compounds promoters used in the transesterification reaction of canola oil and methanol. Sections of this thesis include the synthesis of nanocatalysts, catalyst characterization tests, and investigation of reaction under optimal conditions. Two groups of catalysts containing different weight percentages of alkali metals based on CaO and 1 %wt sodium-potassium based on CaO with different weight percentages of these two elements were synthesized by wet impregnation method and used in the reaction under optimum condition. Catalyst...