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sulfur-determination
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Corrosion investigation of pipeline steel in hydrogen sulfide containing solutions
, Article Journal of Applied Sciences ; Volume 12, Issue 23 , 2012 , Pages 2454-2458 ; 18125654 (ISSN) ; Taheri, H ; Ismail, M. C ; Dolati, A ; Sharif University of Technology
Abstract
The hydrogen-induced cracking (HIC) behavior of X70 pipeline steel was studied by means of Linear Polarization Resistance (LPR), hydrogen permeation tests, weight loss and Scanning Electron Microscopy (SEM). In this study, the dissolved HZS was created by chemical reactions in solution. The specimens were immersed into synthetic sea water saturated with HZS. The experimental results showed that the increase of exposure time and HZS concentration leads to an increase of the hydrogen content in X70 steel, which plays a key role in the initiation and propagation of HIC
Solubility of H2S in 1-(2-hydroxyethyl)-3-methylimidazolium ionic liquids with different anions
, Article Fluid Phase Equilibria ; Volume 298, Issue 2 , November , 2010 , Pages 303-309 ; 03783812 (ISSN) ; Taghikhani, V ; Jalili, A. H ; Mehdizadeh, A ; Safekordi, A. A ; Sharif University of Technology
2010
Abstract
The solubility of hydrogen sulfide in a series of 1-(2-hydroxyethyl)-3-methylimidazolium ([HOemim]+)-based ionic liquids (ILs) containing different anions, viz. hexafluorophosphate ([PF6]-), trifluoromethanesulfonate ([OTf]-), and bis-(trifluoromethyl)sulfonylimide ([Tf2N]-) at temperatures ranging from 303.15 to 353.15K and pressures of up to about 1.8MPa was measured by a volumetric based static apparatus. The solubility data were correlated using two models: (1) the Krichevsky-Kasarnovsky equation and (2) the extended Henry's law combined with the Pitzer's virial expansion for the excess Gibbs energy. Henry's law constants (at zero pressure) in mole-fraction and molality scales were...
Solubility of CO2 and H2S in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate
, Article Journal of Natural Gas Science and Engineering ; Volume 30 , Volume 30 , 2016 , Pages 583-591 ; 18755100 (ISSN) ; Jalili, A. H ; Ghotbi, C ; Rashtchian, D ; Sharif University of Technology
Elsevier
2016
Abstract
The solubility of carbon dioxide and hydrogen sulfide gases in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([C2mim][OTf]) was measured at temperatures from (303.15-353.15) K and pressures up to about 3.0 MPa. The Henry's law constants were determined from the new experimental data, which in turn were used to derive the change of some thermodynamic functions of dissolution of the gases in that particular ionic liquid. The new experimental data were correlated by a combination of the extended Henry's law and Pitzer's model for the excess Gibbs energy. The average relative percent deviation (ARD%) of correlated molality values from experimental data are within...
Characterization of three-dimensional reduced graphene oxide/copper oxide heterostructures for hydrogen sulfide gas sensing application
, Article Journal of Alloys and Compounds ; Volume 740 , 2018 , Pages 1024-1031 ; 09258388 (ISSN) ; Iraji zad, A ; Hosseini, Z. S ; Jokar, E ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Three-dimensional reduced graphene oxide (3D-rGO) structures decorated with CuO particles (GCu) are synthesized through a simple and scalable method for detection of hydrogen sulfide (H2S) gas. For characterization and investigation of porous structure various techniques were employed. Decorated 3D structures demonstrated higher sensitivity and selectivity in comparison to pure structure. Optimized structure for sensing was obtained through introducing different amounts of CuO. The GCu heterostructures containing 35 μmol of CuO powder demonstrated reproducible response of about 30% to the concentration of 10 ppm at room temperature, while complete recovery was obtained through heating to 150...
Study of the solubility of CO2, H2S and their mixture in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate: Experimental and modelling
, Article Journal of Chemical Thermodynamics ; Volume 65 , 2013 , Pages 220-232 ; 00219614 (ISSN) ; Ghotbi, C ; Taghikhani, V ; Jalili, A. H ; Mehdizadeh, A ; Sharif University of Technology
2013
Abstract
New experimental results are presented for the solubility of carbon dioxide, hydrogen sulfide in the ionic liquid 1-octyl-3-methylimidazolium hexafluorophosphate ([C8mim][PF6]) at temperatures range from (303.15 to 353.15) K and pressures up to about 2 MPa. The solubility of the mixture of CO2/H2S in [C8mim][PF6] under various feed compositions were also measured at temperatures of (303.15, 323.15 and 343.15) K and the pressure up to 1 MPa. The solubility of carbon dioxide and hydrogen sulfide increased with increasing pressure and decreased with increasing temperature and the solubility of H2S is about three times that of CO2 in the particular ionic liquid studied. The measured data were...
Effect of anode compositions on the current efficiency of zinc electrowinning
, Article Proceedings - European Metallurgical Conference, EMC 2011 ; Volume 2 , 2011 , Pages 387-396 ; 9783940276377 (ISBN) ; Rashchi, F ; Vahidi, E ; Emami, M ; Khoshnevisan, A ; Sharif University of Technology
Abstract
The main goals in zinc electrowinning process are decreasing of power consumption and increasing of current efficiency. The purpose of this research was to investigate effect of different alloy compositions used in production of lead-based anodes on the zinc electrowinning process. The anode compositions prepared and examined in this study were binary alloys Pb - (0.5 and 2 %) Ag and quaternary alloys Pb - 0.5 % Ag - 1 % Ca - 2 % Sn, Pb - 0.5 % Ag - 1 % Ca - 1 % Sn - 1 % Sb and Pb - 0.5 % Ag - 1 % Ca - 1 % Sn - 1 % Bi. The electrowinning experiments were conducted using a laboratory-scale apparatus, at a plating time of 4 hours, a current density of 500 to 1000 A/m2, industrial zinc sulfate...
Solid nanoparticle and gaseous emissions of a diesel engine with a diesel particulate filter and use of a high-sulphur diesel fuel and a medium-sulphur diesel fuel
, Article Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering ; Volume 231, Issue 7 , 2017 , Pages 941-951 ; 09544070 (ISSN) ; Hosseini, V ; Ehteram, M. A ; Sharif University of Technology
Abstract
High-sulphur and medium-sulphur diesel fuels are still used in several countries. Although diesel particulate filter technology for on-road diesel engines has existed since 1989, the availability of high-sulphur and medium-sulphur diesel fuels in the market causes delays in the use of catalysed filter technologies. However, the situation in places such as Tehran is considered unhealthy because of particles and black carbon, and full distribution of ultra-low-sulphur diesel is awaited eagerly. The purpose of this study is to investigate the effect of the sulphur content in fuels on the gaseous and solid exhaust emissions of a 220 kW Euro II engine equipped with a sintered metal active-passive...
Separation of H2S from CH4 by polymeric membranes at different H2S concentrations
, Article International Journal of Environmental Science and Technology ; Volume 14, Issue 2 , 2017 , Pages 375-384 ; 17351472 (ISSN) ; Savoji, H ; Pourafshari Chenar, M ; Soltanieh, M ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2017
Abstract
In this work, permeation of mixed gases H2S/CH4 through commercial polyphenylene oxide (PPO) hollow fiber and poly (ester urethane) urea (PEUU) flat membranes was studied at pressures of 345–689 kPa, at ambient temperature and at 313.15 K. Various H2S concentrations of about 100–5000 ppm in CH4 binary synthetic gas mixtures as well as a real natural gas sample obtained from a gas refinery containing 0.3360 mol.% H2S (equivalent to 3360 ppm) were tested. It was observed that the permeance of components was affected by the balance between competitive sorption and plasticization effects. Separation factors of H2S/CH4 were in the range of 1.3–2.9, 1.8–3.1 and 2.2–4.3 at pressures of 345, 517 and...
A highly efficient MIL-101(Cr)–Graphene–molybdenum oxide nano composite for selective oxidation of hydrogen sulfide into elemental sulfur
, Article Journal of Industrial and Engineering Chemistry ; Volume 71 , 2019 , Pages 308-317 ; 1226086X (ISSN) ; Askari, S ; Rashidi, A ; Fakhraie, S ; Kooti, M ; Shafiei Alavijeh, M ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2019
Abstract
Hybrid composites of MIL-101(Cr) and Nanoporous Graphene with ratios in the range of 10–50% were prepared via hydrothermal synthesis method. This study deals with an experimental investigation on selective oxidation of H2S into elemental sulfur in the range of 200–270 °C, the catalyst activity and selectivity toward sulfur was studied. High-temperature reactor tests indicated that the MIL-101(Cr)–NPG50–Mo could be a promising candidate with conversion and selectivity of 100% and 99.5% at 200 °C. The MIL-101(Cr)–NPG50–Mo stability showed there were not any significant changes in physical properties, the activity was evaluated after 20 h which was completely stable without any changes
Kinetic and thermodynamic studies of uranium(VI) adsorption using Amberlite IRA-910 resin
, Article Annals of Nuclear Energy ; Volume 39, Issue 1 , January , 2012 , Pages 42-48 ; 03064549 (ISSN) ; Ghaemi, A ; Samadfam, M ; Sharif University of Technology
Abstract
Thermodynamic and kinetic studies have been carried out on the adsorption of uranium(VI) by Amberlite IRA-910 resin. The adsorption process has been investigated as a function of adsorbate concentration, solution acidity, contact time, adsorbent dosage, and temperature. The experiments were preformed in batch mode, where uranium initial concentration on the solution samples were 185.5, 277.6 and 456.8 (mg/lit), sulfuric acid concentration range was 0.02-9 (mol/lit) and sorbent dosages were 0.2, 0.3 and 0.5 g. Equilibrium isotherm data were analyzed using Freundlich and Dubinin-Radushkevich isotherm models. The results showed that the adsorption process was well described by Freundlich...
Investigating the effect of design parameters on the response time of a highly sensitive microbial hydrogen sulfide biosensor based on oxygen consumption
, Article Biosensors and Bioelectronics ; Volume 70 , 2015 , Pages 106-114 ; 09565663 (ISSN) ; Yazdian, F ; Amoabediny, G ; Hakim, M ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
A novel hydrogen sulfide microbial biosensor was developed based on investigating the influence of four design parameters: cell concentration, immobilization bed type, hydrogen sulfide concentration, and geometrical shape of the biosensor. Thiobacillus thioparus was used as the recognition element and it was immobilized on sodium alginate as well as agarose bed. The results were optimized by the application of statistical optimization software based on response time of the system. Oxygen reduction was considered as the detection sign. Sodium alginate solution with a concentration of 2.3% (w/v) and optical density of 10 at 605. nm was found as the optimum conditions for immobilization with...
Effects of alloying elements and microstructure on the susceptibility of the welded HSLA steel to hydrogen-induced cracking and sulfide stress cracking
, Article Materials Science and Engineering A ; Volume 507, Issue 1-2 , 2009 , Pages 167-173 ; 09215093 (ISSN) ; Dolati, A ; Koukabi, A. H ; Sharif University of Technology
2009
Abstract
Hydrogen-induced cracking (HIC) and sulfide stress cracking (SSC) susceptibility of the submerged arc welded API 5L-X70 pipeline steel with different amounts of titanium at two levels of manganese (1.4% and 2%) were studied. The centerline segregation region (CSR) observed in the X70 pipe steel played an important role in the HIC susceptibility. Increased acicular ferrite content in the microstructure improved HIC resistance and SSC resistance, while bainite and martensite/austenite constituents deteriorated the workability of the welded specimens in sour environments. The 2% Mn-series welds showed higher SSC susceptibility than the 1.4% Mn-series welds due to the higher hardness values of...
Novel microfluidic graphene oxide–protein amperometric biosensor for detecting sulfur compounds
, Article Biotechnology and Applied Biochemistry ; Volume 66, Issue 3 , 2019 , Pages 353-360 ; 08854513 (ISSN) ; Abdi, K ; Javadi, S ; Shehneh, M. Z ; Yazdian, F ; Omidi, M ; Rashedi, H ; Haghiralsadat, B. F ; Asayeshnaeini, O ; Sharif University of Technology
Wiley-Blackwell Publishing Ltd
2019
Abstract
Sulfur compounds are essential for many industries and organisms; however, they cause serious respiratory problems in human beings. Therefore, determination of sulfur concentration is of paramount importance. The research approach in the field of detecting contaminants has led to smaller systems that provide faster and more effective ways for diagnosis purposes. In this study, a novel portable amperometric graphene oxide–protein biosensor platform is investigated. The main characteristic of this structure is the implementation of a microfluidic configuration. With albumin metalloprotein as the biorecognition element, graphene oxide was synthesized and characterized by transmission electron...
Fabrication of a sensitive colorimetric nanosensor for determination of cysteine in human serum and urine samples based on magnetic-sulfur, nitrogen graphene quantum dots as a selective platform and Au nanoparticles
, Article Talanta ; Volume 226 , 2021 ; 00399140 (ISSN) ; Dadfarnia, S ; Haji Shabani, A. M ; Kazemi, E ; Pedrini, A ; Verucchi, R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
A novel colorimetric nanosensor is reported for the selective and sensitive determination of cysteine using magnetic-sulfur, nitrogen graphene quantum dots (Fe3O4/S, N-GQDs), and gold nanoparticles (Au NPs). Thus, S, N-GQDs was firstly immobilized on Fe3O4 nanoparticles through its magnetization in the presence of Fe3+ in the alkali solution. The prepared Fe3O4/S, N-GQDs were dispersed in cysteine solution resulting in its quick adsorption on the surface of the Fe3O4/S, N-GQDs through hydrogen bonding interaction. Then, Au NPs solution was added to this mixture that after a short time, the color of Au NPs changed from red to blue, the intensity of surface plasmon resonance peak of Au NPs at...
Fabrication of a sensitive colorimetric nanosensor for determination of cysteine in human serum and urine samples based on magnetic-sulfur, nitrogen graphene quantum dots as a selective platform and Au nanoparticles
, Article Talanta ; Volume 226 , 2021 ; 00399140 (ISSN) ; Dadfarnia, S ; Haji Shabani, A. M ; Kazemi, E ; Pedrini, A ; Verucchi, R ; Sharif University of Technology
Elsevier B.V
2021
Abstract
A novel colorimetric nanosensor is reported for the selective and sensitive determination of cysteine using magnetic-sulfur, nitrogen graphene quantum dots (Fe3O4/S, N-GQDs), and gold nanoparticles (Au NPs). Thus, S, N-GQDs was firstly immobilized on Fe3O4 nanoparticles through its magnetization in the presence of Fe3+ in the alkali solution. The prepared Fe3O4/S, N-GQDs were dispersed in cysteine solution resulting in its quick adsorption on the surface of the Fe3O4/S, N-GQDs through hydrogen bonding interaction. Then, Au NPs solution was added to this mixture that after a short time, the color of Au NPs changed from red to blue, the intensity of surface plasmon resonance peak of Au NPs at...
Oxidative desulfurization of simulated light fuel oil and untreated kerosene
, Article Fuel Processing Technology ; Volume 90, Issue 3 , 2009 , Pages 435-445 ; 03783820 (ISSN) ; Kiaei, Z ; Sobati, M.A ; Sharif University of Technology
2009
Abstract
An experimental investigation was conducted on the oxidative desulfurization of model sulfur compounds such as dibenzothiophene and benzothiophene in toluene as a simulated light fuel oil with a mixture of hydrogen peroxide as the oxidant and various acids as the catalyst. The influences of various parameters including reaction temperature (T), acid to sulfur molar ratio (Acid/S), oxidant to sulfur molar ratio (O/S), type of acid, and the presence of sodium tungstate and commercial activated carbon as a co-catalyst on the fractional conversion of the model sulfur compounds were investigated. The experimental data obtained were used to determine the reaction rate constant of the model sulfur...
Nanorod carbon nitride as a carbo catalyst for selective oxidation of hydrogen sulfide to sulfur
, Article Journal of Hazardous Materials ; Volume 364 , 2019 , Pages 218-226 ; 03043894 (ISSN) ; Eskandari, M. M ; Rashidi, A ; Baghalha, M ; Hassanisadi, M ; Hamzehlouyan, T ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Two-dimensional mesoporous carbon nitride and its highly efficient nanorod framework were prepared via hard-templating method. The obtained materials were fully characterized. The results showed that the samples structural ordering and morphology were similar to those of the parent silica templates; they had large pore volumes as well as high surface area structures. Carbon nitride carbocatalysts were used for H2S selective oxidation. The catalytic tests were carried out at 190, 210 and 230 °C in a fixed bed reactor. The obtained selectivity values for mesoporous carbon nitride rod and mesoporous carbon nitride toward elemental sulfur at 190 °C were 88.8% and 83%, respectively. Both samples...
Highly uniform molybdenum oxide loaded N-CNT as a remarkably active and selective nanocatalyst for H2S selective oxidation
, Article Science of the Total Environment ; Volume 711 , 2020 ; Emrooz, H. B. M ; Rashidi, A ; Hamzehlouyan, T ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Selective oxidation of H2S to elemental sulfur is a low cost and highly efficient process for sulfur removal from H2S-containing hydrocarbon streams in medium scale (i.e. 0.2–10 ton sulfur/day) for environmental protection and prevention of emitting toxic gases to the atmosphere. In this research, in order to prepare a highly active and selective nanocatalyst for selective oxidation of hydrogen sulfide, for the first time, molybdenum oxides were loaded uniformly over nitrogen- doped carbon nanotubes through incipient wetness impregnation. Different metal loadings including 5, 10, and 15 wt% Mo were considered in the synthesis procedure to achieve the optimized performance and provide...