The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Charles Lienemann - One of the best experts on this subject based on the ideXlab platform.
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High-Pressure High-Temperature Transparent Fixed-Bed Reactor for Operando Gas-Liquid Reaction Follow-up
Chemical Engineering and Technology, 2019Co-Authors: Marisa De Sousa Duarte, Matthieu Rolland, Corinne Sagnard, Didier Suire, Frederic Flacher, Olivier Delpoux, Charles LienemannAbstract:A 3 MPa, 350 °C fixed bed reactor has been designed to follow-up gas-liquid-solid reactions on a millimetric size heterogeneous catalyst with Raman spectroscopy. The transparent reactor is a quartz cylinder enclosed in a joule effect heated stainless steel tube. A methodology to determine how to focus the microscope for liquid and solid phase characterization is presented. The setup has been validated by performing diesel Hydrodesulphurisation on a CoMo/Alumina extrudate catalyst with a conversion very close to expected values along with the acquisition of Raman spectra of the solid catalyst showing an evolution of the catalyst phase during sulfidation.
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High‐Pressure High‐Temperature Transparent Fixed‐Bed Reactor for Operando Gas‐Liquid Reaction Follow‐up
Chemical Engineering & Technology, 2019Co-Authors: Marisa De Sousa Duarte, Matthieu Rolland, Corinne Sagnard, Didier Suire, Frederic Flacher, Olivier Delpoux, Charles LienemannAbstract:International audienceA 3 MPa, 350 °C fixed bed reactor has been designed to follow-up gas-liquid-solid reactions on a millimetric size heterogeneous catalyst with Raman spectroscopy. The transparent reactor is a quartz cylinder enclosed in a joule effect heated stainless steel tube. A methodology to determine how to focus the microscope for liquid and solid phase characterization is presented. The setup has been validated by performing diesel Hydrodesulphurisation on a CoMo/Alumina extrudate catalyst with a conversion very close to expected values along with the acquisition of Raman spectra of the solid catalyst showing an evolution of the catalyst phase during sulfidation
Marisa De Sousa Duarte - One of the best experts on this subject based on the ideXlab platform.
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High-Pressure High-Temperature Transparent Fixed-Bed Reactor for Operando Gas-Liquid Reaction Follow-up
Chemical Engineering and Technology, 2019Co-Authors: Marisa De Sousa Duarte, Matthieu Rolland, Corinne Sagnard, Didier Suire, Frederic Flacher, Olivier Delpoux, Charles LienemannAbstract:A 3 MPa, 350 °C fixed bed reactor has been designed to follow-up gas-liquid-solid reactions on a millimetric size heterogeneous catalyst with Raman spectroscopy. The transparent reactor is a quartz cylinder enclosed in a joule effect heated stainless steel tube. A methodology to determine how to focus the microscope for liquid and solid phase characterization is presented. The setup has been validated by performing diesel Hydrodesulphurisation on a CoMo/Alumina extrudate catalyst with a conversion very close to expected values along with the acquisition of Raman spectra of the solid catalyst showing an evolution of the catalyst phase during sulfidation.
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High‐Pressure High‐Temperature Transparent Fixed‐Bed Reactor for Operando Gas‐Liquid Reaction Follow‐up
Chemical Engineering & Technology, 2019Co-Authors: Marisa De Sousa Duarte, Matthieu Rolland, Corinne Sagnard, Didier Suire, Frederic Flacher, Olivier Delpoux, Charles LienemannAbstract:International audienceA 3 MPa, 350 °C fixed bed reactor has been designed to follow-up gas-liquid-solid reactions on a millimetric size heterogeneous catalyst with Raman spectroscopy. The transparent reactor is a quartz cylinder enclosed in a joule effect heated stainless steel tube. A methodology to determine how to focus the microscope for liquid and solid phase characterization is presented. The setup has been validated by performing diesel Hydrodesulphurisation on a CoMo/Alumina extrudate catalyst with a conversion very close to expected values along with the acquisition of Raman spectra of the solid catalyst showing an evolution of the catalyst phase during sulfidation
Jacob A Moulijn - One of the best experts on this subject based on the ideXlab platform.
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Characterisation of alumina- and silica-supported vanadium sulphide catalysts and their performance in hydrotreating reactions
Applied Catalysis A-general, 1999Co-Authors: J.p. Janssens, A. Dick Van Langeveld, Jacob A MoulijnAbstract:Abstract In hydrotreating of heavy oil residua vanadium is deposited on the catalyst surface, which causes a loss in catalyst activity due to active site poisoning and pore plugging. In order to assess the role of the structure in the hydrotreating activity of vanadium, a series of alumina- and silica-supported catalysts has been investigated. The vanadium was characterised by temperature-programmed reduction and temperature-programmed sulphiding. The catalytic performance of vanadium was tested in the Hydrodesulphurisation of thiophene and the hydrodemetallisation of vanadyl-tetraphenylporphyrin. Alumina- and silica-supported vanadium catalysts differ in their dispersion. Vanadium on alumina has a higher dispersion than on silica. This dispersion effect is clearly noticeable in the catalytic activity. Silica-supported catalysts are much less active in the thiophene Hydrodesulphurisation and have a lower hydrogenation rate in the hydrodemetallisation of vanadyl-tetraphenylporphyrin than their alumina-supported counterparts. The two catalyst systems also exhibit large differences in their hydrogenation-hydrogenolysis (ring cleavage) selectivity in the hydrodemetallisation reaction. For alumina-supported vanadium catalysts a higher selectivity for hydrogenation is found than for the silica-supported catalysts. This can be understood by the presence of at least two different types of active sites. Hydrogenation reactions in the hydrodemetallisation occur on structure (dispersion) sensitive sites, whereas ring cleavage can be associated with large clusters of active phase. For both catalyst systems an identical sulphiding mechanism is found to occur. At 1273 K the catalysts are completely sulphided into V2S3, while at 673 K the catalysts are only partially sulphided and are most likely present as an oxy-sulphide.
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the design of base metal catalysts for hydrotreating reactions temperature programmed sulphidation of niw al2o3 catalysts and their activity in the hydrodesulfphurisation of thiophene and dibenzothiophene
Studies in Surface Science and Catalysis, 1997Co-Authors: H R Reinhoudt, Van Ad Dick Langeveld, R Mariscal, De Vhj Vincent Beer, Van Jar Rob Veen, Jacob A MoulijnAbstract:NiW based hydrotreating catalysts have a good performance in Hydrodesulphurisation reactions. It appeared that the their performance in the Hydrodesulphurisation of dibenzothiophene and thiophene strongly depends on their sulphiding degree, which can be controlled by both the calcining and sulphiding temperature. By combining temperature programmed sulphiding with quasi in-situ XPS and activity measurements, it was concluded that the active phase for the HDS of DBT consist of either micro-crystalline sulphided Ni on a WO3 substrate, or of Ni2+ dissolved in the in NiWO4. In contrast, the active phase for the HDS of thiophene seems to consist of Ni-promoted WS2 structures.
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The design of base metal catalysts for hydrotreating reactions : temperature programmed sulphidation of NiW/Al2O3 catalysts and their activity in the hydrodesulfphurisation of thiophene and dibenzothiophene
Hydrotreatment and Hydrocracking of Oil Fractions Proceedings of the 1st International Symposium 6th European Workshop, 1997Co-Authors: H R Reinhoudt, R Mariscal, Van Ad Dick Langeveld, De Vhj Vincent Beer, Van Jar Rob Veen, S.t. Sie, Jacob A MoulijnAbstract:NiW based hydrotreating catalysts have a good performance in Hydrodesulphurisation reactions. It appeared that the their performance in the Hydrodesulphurisation of dibenzothiophene and thiophene strongly depends on their sulphiding degree, which can be controlled by both the calcining and sulphiding temperature. By combining temperature programmed sulphiding with quasi in-situ XPS and activity measurements, it was concluded that the active phase for the HDS of DBT consist of either micro-crystalline sulphided Ni on a WO3 substrate, or of Ni2+ dissolved in the in NiWO4. In contrast, the active phase for the HDS of thiophene seems to consist of Ni-promoted WS2 structures.
Li Zeng - One of the best experts on this subject based on the ideXlab platform.
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recovery of molybdenum and vanadium from synthetic sulphuric acid leach solutions of spent Hydrodesulphurisation catalysts using solvent extraction
Hydrometallurgy, 2010Co-Authors: Li Zeng, Chu Yong ChengAbstract:Abstract A commercially available extractant, LIX®63 was used to investigate the extraction of molybdenum(VI) and vanadium(V) from a synthetic sulphuric acid leach solution of spent Hydrodesulphurisation catalysts. The molybdenum(VI) and vanadium(V) were extracted and separated completely from other metals at pH 1.5. The loaded organic solution was easily stripped by NaOH solution with excellent phase separation. After the precipitation of most of the vanadium(V) as ammonium vanadate from the loaded strip liquor, a pure molybdate solution could be obtained by further removing the small amount of vanadium(V) remaining in the filtrate using Aliquat 336 at pH 8.5. Therefore, both pure molybdenum(VI) and vanadium(V) products can be obtained. The separation of nickel(II) and cobalt(II) from iron(III) and aluminium(III) in the raffinate after the recovery of molybdenum(VI) and vanadium(V) could be achieved by ion exchange with Dowex M4195 resin. A process flowsheet has been developed to recover the valuable metals from leach solutions of spent Hydrodesulphurisation catalysts.
Nishith Verma - One of the best experts on this subject based on the ideXlab platform.
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Maldistribution Effects in an Industrial-Scale Trickle Bed Reactor
Industrial & Engineering Chemistry Research, 2020Co-Authors: Swarup Y. Jejurkar, Ashok Khanna, Nishith VermaAbstract:Phasic maldistribution triggers hot spots within the catalyst bed in a trickle bed reactor. We investigate hot spot formation during hydrodesulphurization of diesel to understand the role of physic...