List of Articles Hydrogen sulfide

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  1 - Modeling of acid gases separation via ionic liquids and membrane and performance comparison between two different membrane
  Behnam Beigi Nadia Esfandiari
  10.30495/jest.2020.35126.4223
  Background and Objective: Natural gas produced from oil and gas wells often contains hydrogen sulfide and carbon dioxide, which are so-called “sour gasses”. Carbon dioxide (in large quantities) and hydrogen sulfide (even in small quantities) cause many probl More

  Background and Objective: Natural gas produced from oil and gas wells often contains hydrogen sulfide and carbon dioxide, which are so-called “sour gasses”. Carbon dioxide (in large quantities) and hydrogen sulfide (even in small quantities) cause many problems during the transmission and consumption of natural gas. In this study, mathematical model for the separation of carbon dioxide and hydrogen sulfide from helium has been investigated with two different membrane species including a ceramic modulus and PEEK-L II and ionic liquids.Material and Methodology: The effect of material, diameter, pressure and temperature on separation efficiency has been investigated. The ionic liquid used in this study is [hemim] [BF4]. The ceramic and PEEK-L II was studied. The pressure and concentration during absorption is investigated. The concentration variations of carbon dioxide and hydrogen sulfide in ionic fluid were investigated in time.Findings: For a ceramic modulus, about 50 to 60% of the pressure drop occurs in the first 100 to 120 seconds. For the PEEK-L II modulus, in the first 30 seconds, about 50 to 60% of the pressure drop occurs due to gas absorption. The effect of temperature on the concentration of carbon dioxide and hydrogen sulfide at three temperatures of 25, 50 and 100 °C was investigated. As the temperature rises in the ceramic modulus, the amounts of carbon dioxide and hydrogen sulfide, passing through the membrane, increase.Discussion and Conclusion: As the time increases, the concentrations of carbon dioxide and hydrogen sulfide in the ionic fluid are increasing. With increasing temperature from 25 to 100 ° C, the amount of absorbed acidic gases into ionic liquid was increased. The PEEK-L II modules removed more acidic gases than the ceramic modules. Manuscript profile
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  2 - Mathematical Modeling of H2S Removal in a Bio-Filter
  Amir Rahimi Samaneh Sami
  In this study, A mathematical model has been developed for H2S removal in a bio-filter. The modelis used for analyzing the bio-filter performance in steady and unsteady state operation conditions. Thegoverning equations including the concentration distribution equations More

  In this study, A mathematical model has been developed for H2S removal in a bio-filter. The modelis used for analyzing the bio-filter performance in steady and unsteady state operation conditions. Thegoverning equations including the concentration distribution equations for pollutant component andoxygen in the gas and biofilm phases were derived based on the conservation laws and solvednumerically. The change of pollutant concentration through the bio-filter length and bio-film thicknesswas obtained. The model predictions for removal efficiency and elimination capacity in three differentgas flow rates (0.03, 0.07 and 0.14 m3/hr) and different inlet concentrations, compared with theexperimental data reported by Oyarzun et al., and the accuracy of the model results was obtained. Alsothe results of the model for unsteady state operation condition were obtained for 1100 ppm of inletconcentration of H2S. These values compared with the existing experimental data too. Finally theeffect of some operation parameters such as: specific surface area of the bed, height of the bed,porosity of the bed and gas flow rate, on the removal efficiency of bio-filter was investigated. Manuscript profile
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  3 - Hazards of Tunnel Excavation in H2S-bearing Grounds: (Case study of Aspar Tunnel)
  Hossein Mirmehrabi Mohammad Ghafoori Gholamreza Lashkaripour Jafar Hassanpour
  AbstractIntroduction: Encountering hydrogen sulfide gas (H2S) during excavation is one of the important engineering,geological and environmental hazards during the tunnelling. Tackling this hazard and solving its challengessolving are very difficult and costly. During i More

  AbstractIntroduction: Encountering hydrogen sulfide gas (H2S) during excavation is one of the important engineering,geological and environmental hazards during the tunnelling. Tackling this hazard and solving its challengessolving are very difficult and costly. During investigation of the situation, one of the main tasks is prediction orevaluation of the risk of H2S gas and selection of the best methods to tackle its engineering and environmentalproblems. In this study, water conveyance tunnel of Aspar excavated in H2S bearing environment is discussed.This tunnel is excavated in the hydrocarbon formations. In this paper, hazards, characteristics, safety regulations,and geological sources of H2S as well as the methods to decrease the risks and problems in excavation of thetunnel are presented in brief.Methods: In order to determine the source of gas and to select the best methods to mitigate its hazards andproblems, in addition to investigation of the same experiences, concentration of various gases was recorded byfixed stations on the machine and by mobile sensors at the beginning, midpoint and end of each working shift.Moreover, sampling of the polluted air and water was implemented. The samples were sent to a specificlaboratory for chemical analysis. At the same time, concentration of the gas in the air and water of the tunnel wasmeasured.Results: Experiments raleted to the tunnel showed that the gas caused an unacceptable condition for workers.For predicting the risk of H2S gas in underground spaces, it is possible to use some evidences such as sulfursprings, organic traces, organic shales, exposure of H2S odor from fresh surface of rock, and smelling of H2Sduring boreholes drilling. Results of the analysis show that the gas enters the tunnel along with water,dominantly. Also considerable amount of the gas is released to the air at the beginning. According to theinvestigations, the source of the gas is relevant to hydrocarbon formations inthe area.Conclusion: Geological formations related to hydrocarbon resources are very important in the formation andreservation of H2S gas. Since the gas is in solution form and is emitted promptly, controlling the inflow ofgroundwater into the excavation, diluting the concentration of H2S and training the workers are a series ofmethods used to decrease the risks and problems associated with tunnel excavation in an H2S-bearingenvironment. Manuscript profile
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  4 - A Theoretical Study of H2S and CO2 Interaction with the Single-Walled Nitrogen Doped Carbon Nanotubes
  M. Oftadeh M. Rezaeisadat A. Rashidi
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  5 - A review of Superclaus process catalysts for sulfur recovery
  Sedigheh Sadegh Hassani raheleh saeedi rad elham yagoubpour ali chesheh roshan sepehr sedighi maryam mashayekhi
  10.30495/jacr.2022.1947335.2003
  Hydrogen sulfide is a by-product of processes related to fossil fuels (such as natural gas and crude oil). Selective oxidation of hydrogen sulfide process (superclaus) following the claus process used to convert residual hydrogen sulfide to sulfur and plays a major role More

  Hydrogen sulfide is a by-product of processes related to fossil fuels (such as natural gas and crude oil). Selective oxidation of hydrogen sulfide process (superclaus) following the claus process used to convert residual hydrogen sulfide to sulfur and plays a major role in controlling and reducing pollutant gases. The catalysts used in this process play a very important role in the production efficiency of elemental sulfur and various materials can be used as catalysts to decrease hydrogen sulfide. These catalysts have specific surface area, porosity, mechanical resistance, particle size distribution, acidity, and other special properties that distinguish them for converting hydrogen sulfide to sulfur. In this study, different types of catalysts that used in the superclaus process are investigated. In this regard, support based catalysts including metal oxides, carbon compounds, zeolites and clays supports as well as supportless catalysts including metal oxides, iron, and vanadium in the selective oxidation of hydrogen sulfide to sulfur are investigated. Manuscript profile
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  6 - Magnesium ferrite/reduced graphene oxide nanocomposite and its photocatalytic application in pollutant degradation and fuel production
  majid Ghanimati Mohsen Lashgari Vassilios Binas
  10.30495/jacr.2023.1984952.2120
  Preparation of effective nanocomposite energy materials using Earth-abundant elements and eco-friendly chemicals for application in photocatalytic degradation of hazardous materials and production of fuel is a sustainable strategy for pollutant removal and supplying hyd More

  Preparation of effective nanocomposite energy materials using Earth-abundant elements and eco-friendly chemicals for application in photocatalytic degradation of hazardous materials and production of fuel is a sustainable strategy for pollutant removal and supplying hydrogen, the green/carbon-free fuel in modern world. In this article, the nanostructured magnesium ferrite (MgFe2O4) semiconductor was synthesized and employed for the production of hydrogen gas through the light-induced splitting of alkaline H2S solution and photocatalytic degradation of methyl orange–a refractory azo dye. Investigations revealed that the synthesized photocatalyst has the ability to destroy pollutant and produce hydrogen. To improve the photocatalyst activity, graphene oxide (GO) precursor was prepared through the modified Hummers method and utilized directly in the hydrothermal synthesis of MgFe2O4/rGO nanocomposite. The evidence showed that the presence of rGO (reduced graphene oxide) and the formation of nanocomposite can significantly increase the decolorization ability and hydrogen release in terms of enlarging the photocatalyst surface area, slowing down the electron-hole recombination, and enhancing photon absorption. The degradation efficiency was 84% [measured after one hour operation of the photoreactor] and the rate of hydrogen release was 5567 µmol/h [per gram of photocatalyst], indicated the good performance of the nanocomposite photocatalyst in pollutant removal and fuel production Manuscript profile