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Development of a continuous kinetic model for prediction of coke formation in hydroconversion of Marlim crude oil in a slurry-phase reactor
, Article Petroleum and Coal ; Vol. 56, issue. 3 , 2014 , p. 249-256 ; Khorasheh, F ; Sharif University of Technology
Abstract
A Continuous model was developed to describe the kinetics of hydroconversion of Marlim crude oil in a slurry-phase reactor. The model was able to accurately predict the liquid product distributions as well as coke formation. The model contained one temperature-independent and six temperature-dependent parameters.The model parameters were obtained by an optimization procedure using experimental data available in the open literature for reaction temperatures of 440-460°C, hydrogen pressure of 14.7 MPa, liquid hourly space velocity (LHSV) of 0.5 h-1, and a hydrogen to oil ratio of 100 to 1 ft3/bbl. Comparison between experimental and predicted product distributions and coke yields indicated a...
Preparation and study of bi-supported Ziegler-Natta catalyst with nano graphene oxide and magnesium ethoxide supports for polymerization of polyethylene
, Article Polymer Science - Series B ; Volume 58, Issue 3 , 2016 , Pages 271-277 ; 15600904 (ISSN) ; Ramazani SaadatAbadi, A ; Khorasheh, F ; Baghalha, M ; Bahrami, H ; Sharif University of Technology
Maik Nauka-Interperiodica Publishing
2016
Abstract
In this study, we have reported the preparation of bi-supported Ziegler-Natta catalysts using magnesium ethoxide and graphene oxide as support. The polymerization process was carried out in slurry phase using triisobutylaluminum as a co-catalyst.The XRD analysis of TiCl4/graphene oxide/Mg(OEt)2 catalyst demonstrated that the space between the layers of graphene oxide had increased to 0.2 nm.The catalyst was characterized by XPS, BET, BJH, SEM, and TGA. The catalyst activity was studied for various Al/Ti molar ratios, and the catalyst activity was optimum at Al/Ti molar ratio of 315. © 2016, Pleiades Publishing, Ltd
Photocatalytic Reactor Design for Elimination of Pharmaceutical Pollutants from Wastewater
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Ghasemi, Shahnaz (Co-Supervisor)
Abstract
Due to the increasing number of Advanced Oxidation Processes (AOPs) that are exploited to eliminate emerging and recalcitrant contaminants from water supplies, photocatalytic degradation of Reactive Blue 21 dye using Zinc Oxide nanoparticles is investigated in both a slurry phase and an immobilized photoreactor. The structural and optical properties of the prepared ZnO nanoparticles were examined by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and UV-Visible Diffuse Reflectance Spectroscopy (UV-vis DRS). The effects of photocatalyst concentration, calcination temperature, pH and UV lamps were optimized in the slurry phase photoreactor. It was shown that 250 ppm of ZnO that was...
Preparation of ultrahigh-molecular-weight polyethylene/carbon nanotube nanocomposites with a Ziegler-Natta catalytic system and investigation of their thermal and mechanical properties
, Article Journal of Applied Polymer Science ; Volume 125, Issue SUPPL. 1 , 2012 , Pages E453-E461 ; 00218995 (ISSN) ; Ramazani, S. A. A ; Izadi, H ; Sharif University of Technology
Wiley
2012
Abstract
In this research, ultrahigh-molecular-weight polyethylene (UHMWPE)/multiwalled carbon nanotube (MWCNT) nanocomposites with different nanotube concentrations (0.5, 1.5, 2.5, and 3.5 wt %) were prepared via in situ polymerization with a novel, bisupported Ziegler-Natta catalytic system. Magnesium ethoxide [Mg(OEt) 2] and surface-functionalized MWCNTs were used as the support of the catalyst. Titanium tetrachloride (TiCl 4) accompanied by triethylaluminum constituted the Ziegler-Natta catalytic system. Preparation of the catalyst and the polymerization were carried out in the slurry phase under an argon atmosphere. Support of the catalyst on the MWCNTs was investigated with Fourier transform...
Synthesis of dimethyl ether over modified H-mordenite zeolites and bifunctional catalysts composed of Cu/ZnO/ZrO2 and modified H-mordenite zeolite in slurry phase
, Article Catalysis Letters ; Volume 129, Issue 1-2 , 2009 , Pages 111-118 ; 1011372X (ISSN) ; Kazemeini, M ; Aghaziarati, M ; Sharif University of Technology
2009
Abstract
Synthesis of dimethyl ether (DME) via methanol dehydration were investigated over various catalysts, and via direct CO hydrogenation over hybrid catalysts composed of Al-modified H-Mordenite zeolite and Cu/ZnO/ZrO 2. H-Mordenite zeolite exhibited the highest activity in dehydration of methanol. However, its selectivity toward dimethyl ether was rather low. For this reason, the H-Mordenite was modified. Modification of zeolites was performed by wet impregnation method and considered catalysts were characterized by AAS, XRD and NH3-TPD analyses. Results of catalytic tests indicated that H-Mordenite modified with 8 wt% aluminum oxide was the best catalyst for synthesis of dimethyl ether from...
Investigation of properties of polyethylene/clay nanocomposites prepared by new in situ ziegler-natta catalyst
, Article Materials and Design ; Volume 30, Issue 7 , 2009 , Pages 2309-2315 ; 02641275 (ISSN) ; Ramazani Saadat Abadi, A ; Baniasadi, H ; Tavakolzadeh, F ; Sharif University of Technology
2009
Abstract
This paper is devoted to investigation of morphological and physical-mechanical properties of polyethylene (PE)/clay nanocomposites prepared via in situ polymerization method using bi-supported Ziegler-Natta catalyst. Bentonite type clay and MgCl2 (ethoxide type) were used as the support of TiCl4. Catalyst support and polymerization process have been done in slurry phase using Triisobutylaluminum as the co-catalyst. The microstructure of the nanocomposites was examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD and TEM indicated that almost fully exfoliated PE/clay nanocomposites were produced successfully using this method. According to permeability...