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L. N. Khairulina - One of the best experts on this subject based on the ideXlab platform.
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Catalytic reactions of Dimethyl Disulfide with thiophene and benzene
Kinetics and Catalysis, 2016Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The gas-phase reaction of Dimethyl Disulfide with thiophene proceeds under the action of acid catalysts under atmospheric pressure at 160–350°C and a residence time of τ = 0.6–21 s to form thioalkylation and alkylation products. Dimethyl Disulfide reacts with benzene to form only alkylation products. Catalysts containing both strong protic and Lewis acid sites, as well as basic sites of moderate strength, are the most active ones.
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Reaction of Dimethyl Disulfide with thiophene catalyzed by zeolite
Russian Journal of Organic Chemistry, 2015Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:Reaction of Dimethyl Disulfide with thiophene under the action of highly siliceous zeolite at 180–350°C and contact time 0.6–14 s resulted in formation of thioalkylation products, 2-(methylsulfanyl)- and 2,5-bis(methylsulfanyl)thiophenes and also alkylated derivatives, 2-methyl-, 2,5-Dimethyl-, and 2,3,4-trimethylthiophenes.
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Methylation of benzene with Dimethyl Disulfide
Russian Journal of Organic Chemistry, 2015Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:Dimethyl Disulfide reacts with benzene at 250–350°C over a period of 1–20 s in the presence of catalysts containing strong Bronsted and Lewis acid centers to give a mixture of methylbenzenes, viz. toluene, isomeric xylenes, mesitylene, and durene.
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Catalytic synthesis of Dimethyl sulfide from Dimethyl Disulfide and methanol
Russian Journal of Applied Chemistry, 2012Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The reaction of Dimethyl Disulfide with methanol was studied at atmospheric pressure and temperature of 350°C in the presence of catalysts containing acid and basic sites.
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Dimethyl Disulfide conversion into Dimethyl sulfide in the presence of sulfidized catalysts
Kinetics and Catalysis, 2010Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The conversion of Dimethyl Disulfide in the presence of various supported sulfidized metal-containing catalysts at atmospheric pressure and T = 150−350°C was studied. Sulfidized transition metals supported onto aluminum oxide were more active than catalysts based on a carbon support, silicon dioxide, amorphous aluminosilicate, and zeolite ZSM-5. The most active catalyst was 10% Co/Al2O3 prepared with the use of cobalt acetate as an active component precursor and treated with a mixture of hydrogen sulfide with hydrogen at T = 400°C. From kinetic data, it follows that all of the reaction products were formed simultaneously at a temperature of
A. V. Mashkina - One of the best experts on this subject based on the ideXlab platform.
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Catalytic reactions of Dimethyl Disulfide with thiophene and benzene
Kinetics and Catalysis, 2016Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The gas-phase reaction of Dimethyl Disulfide with thiophene proceeds under the action of acid catalysts under atmospheric pressure at 160–350°C and a residence time of τ = 0.6–21 s to form thioalkylation and alkylation products. Dimethyl Disulfide reacts with benzene to form only alkylation products. Catalysts containing both strong protic and Lewis acid sites, as well as basic sites of moderate strength, are the most active ones.
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Reaction of Dimethyl Disulfide with thiophene catalyzed by zeolite
Russian Journal of Organic Chemistry, 2015Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:Reaction of Dimethyl Disulfide with thiophene under the action of highly siliceous zeolite at 180–350°C and contact time 0.6–14 s resulted in formation of thioalkylation products, 2-(methylsulfanyl)- and 2,5-bis(methylsulfanyl)thiophenes and also alkylated derivatives, 2-methyl-, 2,5-Dimethyl-, and 2,3,4-trimethylthiophenes.
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Methylation of benzene with Dimethyl Disulfide
Russian Journal of Organic Chemistry, 2015Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:Dimethyl Disulfide reacts with benzene at 250–350°C over a period of 1–20 s in the presence of catalysts containing strong Bronsted and Lewis acid centers to give a mixture of methylbenzenes, viz. toluene, isomeric xylenes, mesitylene, and durene.
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Catalytic synthesis of Dimethyl sulfide from Dimethyl Disulfide and methanol
Russian Journal of Applied Chemistry, 2012Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The reaction of Dimethyl Disulfide with methanol was studied at atmospheric pressure and temperature of 350°C in the presence of catalysts containing acid and basic sites.
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Dimethyl Disulfide conversion into Dimethyl sulfide in the presence of sulfidized catalysts
Kinetics and Catalysis, 2010Co-Authors: A. V. Mashkina, L. N. KhairulinaAbstract:The conversion of Dimethyl Disulfide in the presence of various supported sulfidized metal-containing catalysts at atmospheric pressure and T = 150−350°C was studied. Sulfidized transition metals supported onto aluminum oxide were more active than catalysts based on a carbon support, silicon dioxide, amorphous aluminosilicate, and zeolite ZSM-5. The most active catalyst was 10% Co/Al2O3 prepared with the use of cobalt acetate as an active component precursor and treated with a mixture of hydrogen sulfide with hydrogen at T = 400°C. From kinetic data, it follows that all of the reaction products were formed simultaneously at a temperature of
W T Tysoe - One of the best experts on this subject based on the ideXlab platform.
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low temperature shear induced tribofilm formation from Dimethyl Disulfide on copper
ACS Applied Materials & Interfaces, 2011Co-Authors: Octavio Javier Furlong, P.v. Kotvis, Brendan P. Miller, W T TysoeAbstract:The frictional properties of a sliding copper-copper interface exposed to Dimethyl Disulfide (DMDS) are measured in UHV under conditions at which the interfacial temperature rise is <1 K. A significant reduction in friction is found from the clean-surface values and sulfur is found on the surface and below the surface in the wear scar region by Auger spectroscopy. Because the interfacial temperature rise under the experimental conditions used to measure friction is very small, tribofilm formation is not thermally induced. The novel, low-temperature tribofilm formation observed here is ascribed to a shear-induced intermixing of the surface layer(s) with the subsurface region as suggested using previous molecular dynamics simulations. Although the tribofilm contains predominantly sulfur, a small amount of carbon is also found in the film.
Octavio Javier Furlong - One of the best experts on this subject based on the ideXlab platform.
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low temperature shear induced tribofilm formation from Dimethyl Disulfide on copper
ACS Applied Materials & Interfaces, 2011Co-Authors: Octavio Javier Furlong, P.v. Kotvis, Brendan P. Miller, W T TysoeAbstract:The frictional properties of a sliding copper-copper interface exposed to Dimethyl Disulfide (DMDS) are measured in UHV under conditions at which the interfacial temperature rise is <1 K. A significant reduction in friction is found from the clean-surface values and sulfur is found on the surface and below the surface in the wear scar region by Auger spectroscopy. Because the interfacial temperature rise under the experimental conditions used to measure friction is very small, tribofilm formation is not thermally induced. The novel, low-temperature tribofilm formation observed here is ascribed to a shear-induced intermixing of the surface layer(s) with the subsurface region as suggested using previous molecular dynamics simulations. Although the tribofilm contains predominantly sulfur, a small amount of carbon is also found in the film.
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Low-temperature, shear-induced tribofilm formation from Dimethyl Disulfide on copper.
ACS Applied Materials & Interfaces, 2011Co-Authors: Octavio Javier Furlong, P.v. Kotvis, Brendan P. Miller, Wilfred T. TysoeAbstract:The frictional properties of a sliding copper-copper interface exposed to Dimethyl Disulfide (DMDS) are measured in UHV under conditions at which the interfacial temperature rise is
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The surface chemistry of Dimethyl Disulfide on copper
Langmuir, 2010Co-Authors: Octavio Javier Furlong, Brendan P. Miller, Joshua Walker, Luke Burkholder, Wilfred T. TysoeAbstract:The surface chemistry of Dimethyl Disulfide (DMDS) is studied on a Cu(111) single crystal and a polished copper foil in ultrahigh vacuum as a basis for understanding its tribological chemistry using a combination of temperature-programmed desorption (TPD), reflection-absorption infrared spectroscopy (RAIRS), and X-ray photoelectron spectroscopy (XPS). Low-energy electron diffraction reveals that the polished foil becomes ordered on heating in vacuo and displays identical surface chemistry to that found on the Cu(111) surface. Dimethyl Disulfide reacts with the copper surface at 80 K to form thiolate species. Heating the surface to ∼230 K causes a small portion of the thiolate species to decompose to form methyl groups adsorbed on the surface. Further heating results in methane and C(2) hydrocarbon desorption at ∼426 K, due to a reaction of adsorbed methyl species, to completely remove carbon from the surface and to deposit atomic sulfur.
Guy Marin - One of the best experts on this subject based on the ideXlab platform.
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influence of Dimethyl Disulfide on coke formation during steam cracking of hydrocarbons
Industrial & Engineering Chemistry Research, 2007Co-Authors: Jidong Wang, Marie-françoise Reyniers, Guy MarinAbstract:The influence of Dimethyl Disulfide (DMDS), which is widely used as an additive in ethylene plants, on coke formation during the steam cracking of hydrocarbons was investigated in a continuous-flow stirred-tank reactor (CSTR) setup with n-hexane as the feed and in a pilot-plant setup with ethane as the feed. Both of the reactors were made of Incoloy 800HT. Experiments were carried out at conditions relevant to industrial steam crackers. DMDS was applied by presulfidation, continuous addition, and presulfidation followed by continuous addition. Application of DMDS suppresses CO production. The influence of DMDS on coke formation was found to depend on the application method and the amount of DMDS used. SEM examination of the coke samples obtained from the steam cracking of n-hexane indicated that application of DMDS leads to a significant change in the coke morphology. EDX analysis indicated that application of DMDS causes a significant change in the metal content and distribution in both the alloy surface...
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the influence of Dimethyl Disulfide on naphtha steam cracking
Industrial & Engineering Chemistry Research, 2001Co-Authors: Inge Dhuyvetter, Gilbert F. Froment, Marie-françoise Reyniers, Guy Marin, Dominique ViennetAbstract:A pilot unit for steam cracking equipped with a transfer line heat exchanger (TLE) that allows for the study of coke deposition in both the reactor and the TLE is presented. The reactor and TLE are made of Incoloy 800HT. The duration of a coking run typically amounts to 32.4 ks. The influence of different Dimethyl Disulfide (DMDS) addition procedures, i.e., continuous addition, presulfidation and presulfidation followed by continuous addition, on CO production and on coke deposition in the reactor and in the TLE during naphtha cracking is investigated. Presulfidation reduces CO production. However, to obtain a low and stable CO production, continuous addition of sulfur is required. The influence of sulfur addition on coke formation in the reactor can strongly differ from its influence on coke formation in the TLE. In the reactor, as well as in the TLE, the observed influence of sulfur addition is complex and strongly depends on the technique used. The optimal operating conditions for reducing CO production and minimizing coke formation consist of presulfidation followed by continuous dosing.