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The study presents complementary experiments and quantum chemical DFT computations to reveal the molecular-level interactions of an advanced nanomaterial, porphyrin aluminum metal–organic framework (compound 2), with the volatile organic sulfur compound diethyl sulfide (DES). First, the intermolecular host–guest interactions during the sorption of DES were explored under dynamic conditions, using the vapor of DES in flowing air. The in situ time-dependent ATR-FTIR spectroscopy in a controlled atmosphere was significantly improved though the use of a new facilely built spectroscopic mini-chamber. The binding site of DES in compound 2 involves the μ(O–H) and COO- groups of the linker of the sorbent. Further, the chemical kinetics of the sorption of DES was investigated, and it follows the Langmuir adsorption kinetic model. That is, depending on the time interval, the process obeys either the pseudo-first- or pseudo-second-order rate law. For the Langmuir adsorption of the pseudo-first order, the rate constant is robs = 0.165 ± 0.017 min−1. Next, the interaction of compound 2 with the saturated vapor of DES yields the adsorption complex compound 3 [Al-MOF-TCPPH2]2(DES)7. The adsorbed amount of DES is very large at 36.5 wt.% or 365 mg/g sorbent, one of the highest values reported on any sorbent. The molecular modes of bonding of DES in the complex were investigated through quantum chemical DFT computations. The adsorption complex was facilely regenerated by gentle heating. The advanced functional material in this work has significant potential in the environmental remediation of diethyl sulfide and related volatile organic sulfur compounds in air, and it is an interesting target of mechanistic studies of sorption. [ABSTRACT FROM AUTHOR]

One of the most important operations in refineries is a purification operation, and its purpose is to eliminate or reduce sulfur compounds and other disturbing compounds. Diethyl sulfide and benzothiophene pollutants are among the compounds that desulfurization is always associated with problems in the oil industry and their separation requires high costs or new technologies. The aim of this study is to investigate the zinc oxide nano-cage using to identify and remove these pollutants, is simulated and calculated the effects of adsorption, and sensitivity of zinc oxide nano-cage removes diethyl sulfide and benzotiophenine pollutants. To calculate the interaction of pollutants with nano-adsorbent, first all structures are optimized separately, and then the interaction between them is simulated and is optimized their geometric structure. On the zinc oxide nano-cage (Zn12O12-NC), there are two different spatial positions with a bond length of 1.95 and 1.89 Å for the Zn-O bond, as well as another location in the inner cavity of the nano-cage. The thermodynamic and structural parameters have been evaluated and calculated on these three spatial positions with pollutants. The results show that the Zn12O12-NC has no tendency to enter the pollutants into the inner cavity (3rd position) but tend to interact with them in two spatial positions in its outer wall, the aliphatic compound of diethyl sulfide in 2nd position and the aromatic compound of benzotiophenine in the 1st position are better absorbed on the nano-cage and easily lose the H2S composition. [ABSTRACT FROM AUTHOR]

The study presents complementary experiments and quantum chemical DFT computations to reveal the molecular-level interactions of an advanced nanomaterial, porphyrin aluminum metal–organic framework (compound 2), with the volatile organic sulfur compound diethyl sulfide (DES). First, the intermolecular host–guest interactions during the sorption of DES were explored under dynamic conditions, using the vapor of DES in flowing air. The in situ time-dependent ATR-FTIR spectroscopy in a controlled atmosphere was significantly improved though the use of a new facilely built spectroscopic mini-chamber. The binding site of DES in compound 2 involves the μ(O–H) and COO- groups of the linker of the sorbent. Further, the chemical kinetics of the sorption of DES was investigated, and it follows the Langmuir adsorption kinetic model. That is, depending on the time interval, the process obeys either the pseudo-first- or pseudo-second-order rate law. For the Langmuir adsorption of the pseudo-first order, the rate constant is robs = 0.165 ± 0.017 min−1. Next, the interaction of compound 2 with the saturated vapor of DES yields the adsorption complex compound 3 [Al-MOF-TCPPH2]2(DES)7. The adsorbed amount of DES is very large at 36.5 wt.% or 365 mg/g sorbent, one of the highest values reported on any sorbent. The molecular modes of bonding of DES in the complex were investigated through quantum chemical DFT computations. The adsorption complex was facilely regenerated by gentle heating. The advanced functional material in this work has significant potential in the environmental remediation of diethyl sulfide and related volatile organic sulfur compounds in air, and it is an interesting target of mechanistic studies of sorption.

The kinetics of oxidation of diethyl sulfide (Et2S) with hydrogen peroxide (H2O2) in aqueous solutions of acetonitrile (MeCN) was studied using a kinetic distribution method. It was found that the order of the reaction with respect to the substrate depends on pH and changes from the first at pH 8.06 to nearly zero at pH 11.02. The initial rates of Et2S consumption increase with pH and linearly depend on the concentrations of the hydroperoxide anion (HOO–) and MeCN. It was assumed that the reaction involves the nonequilibrium formation of peroxyimidate in the slow stage of the interaction of HOO– with MeCN followed by the rapid oxidation of Et2S. [ABSTRACT FROM AUTHOR]

Copper(I) thiocyanate (CuSCN) is rising to prominence as a hole‐transporting semiconductor in various opto/electronic applications. Its unique combination of good hole mobility, high optical transparency, and solution‐processability renders it a promising hole‐transport layer for solar cells and p‐type channel in thin‐film transistors. CuSCN is typically deposited from sulfide‐based solutions with diethyl sulfide (DES) being the most widely used. However, little is known regarding the effects of DES on CuSCN films despite the fact that DES can coordinate with Cu(I) and result in a different coordination polymer having a distinct crystal structure when fully coordinated. Herein, the coordination of DES in CuSCN films is thoroughly investigated with a suite of characterization techniques as well as density functional theory. This study reveals that DES directly affects the microstructure of CuSCN by stabilizing the polar crystalline surfaces via the formation of strong coordination bonds. Furthermore, a simple antisolvent treatment is demonstrated to be effective at modifying the microstructure and morphology of CuSCN films. The treatment with tetrahydrofuran or acetone leads to uniform films consisting of CuSCN crystallites with high crystallinity and their surfaces passivated by DES molecules, resulting in an increase in the hole mobility from 0.01 to 0.05 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Composite TiO2/activated carbon (TiO2/AC) and TiO2/SiO2 photocatalysts with TiO2 contents in the 10 to 80 wt. % range were synthesized by the TiOSO4 thermal hydrolysis method and characterized by AES, BET, X-ray diffraction and FT-IR ATR methods. All TiO2 samples were in the anatase form, with a primary crystallite size of about 11 nm. The photocatalytic activities of the TiO2/AC and TiO2/SiO2 samples were tested in the gas-phase photocatalytic oxidation (PCO) reaction of diethyl sulfide (DES) vapor in a static reactor by the FT-IR in situ method. Acetaldehyde, formic acid, ethylene and SO2 were registered as the intermediate products which finally were completely oxidized to the final oxidation products – H2O, CO2, CO and SO42− ions. The influence of the support on the kinetics of DES PCO and on the TiO2/AC and TiO2/SiO2 samples’ stability during three long-term DES PCO cycles was investigated. The highest PCO rate was observed for TiO2/SiO2 photocatalysts. To evaluate the activity of photocatalysts the turnover frequency values (TOF) were calculated for three photocatalysts (TiO2, TiO2/AC and TiO2/SiO2) for the same amount of mineralized DES. It was demonstrated that the TOF value for composite TiO2/SiO2 photocatalysts was 3.5 times higher than for pure TiO2.

Vapor phase catalytic degradation of diethyl sulfide (DES) (simulant of sulfur mustard: a potential chemical warfare agent) at higher concentration (∼1200 ppm) was carried out in a fixed bed flow reactor over MnO/zeolite‐13X catalysts of different manganese contents. The catalytic process was studied in the temperature range of 100–400°C with air as the oxidizing agent. Process parameters such as reaction temperature, metal content, gas hourly space velocity, and RH% were optimized for 100% degradation of DES vapors. Reaction temperature and RH% has significant influence over the activity and stability of MnO/zeolite‐13X catalyst. The major degradation products identified are carbon oxides, ethylene, acetaldehyde, and sulfur dioxide. Traces of diethyl sulfoxide and diethyl sulfone, CSO, ethanol, thioethanol, methane thiol, acetic acid, formic acid, and thiophene are also identified in GC‐MS analyses. The plausible degradation pathway of DES is also proposed based on the analyses results. The MnO/zeolite‐13X catalysts of different compositions are prepared by wet impregnation method and characterized by different characterization techniques. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1705–1712, 2018 [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Module performance for removal of different sulfur containing species are analyzed. • An appropriate mathematical model is used to predict performance theoretically. • Membrane transport parameters are predicted by using experimental results. • Modules are found selective for different sulfur containing species. • Module selectivity for thiophene reduces with increasing its molecular weight. Abstract In last decade, pervaporation has been recognized as a promising novel process for desulfurization of FCC (Fluidized Catalytic Cracking) gasoline. This study deals with the comparison of the removal of different types of sulfur containing species by a spiral wound pervaporation module. For this, different binary systems containing 2-methyl thiophene, 1-butanethiol and diethyl sulfide as solute and n -heptane as solvent are selected as model gasoline. Results reported in our previous study on n -heptane/thiophene systems are also included in the analysis. Experiments were performed on a spiral wound module with PDMS/PI (Polydimethylsiloxane/Polyimide) composite membrane at a variety of operating conditions. A suitable mathematical model was then used to predict the module performance theoretically. Some of the experimental results were used to predict the membrane transport parameters for different sulfur containing compounds, and the remaining experimental results were then used to validate the mathematical model. Comparison of the model predictions and experimental results validated the mathematical model, which suggests that the reported mathematical model can be applied to design the spiral wound pervaporative modules to remove higher molecular weight thiophenes as well as other sulfur containing compounds. The presented results show that the PDMS/PI membrane is selective for all three sulfur containing compounds. However, the pervaporation process is found more suitable for removal of lower molecular weight thiophenes. Results further show that the optimum operating conditions for sulfur removal may depend on the functional groups present and molecular weight of sulfur containing compounds present in the gasoline. [ABSTRACT FROM AUTHOR]

Human kidney-type glutaminase (KGA) is an important target that is often over expressed in many cancer cells but very few effective inhibitors of this enzyme have yet reached clinical trials. Caudatan A and caudatan B, two undescribed tetracyclic flavans with an unusual ether bond between the C-4 and C-2′ were isolated from the roots of Ohwia caudata (Thunb.) H.Ohashi. Caudatan A exhibited stronger inhibitory activity and caudatan B showed moderate effect from the results of inhibitory activities evaluations on KGA. The molecular docking and primary structure-activity relationship analysis revealed that the less steric hindrance at ring A was necessary to the effect. Therefore, combined its better solubility than that of bis-2-(5-phenylacetimido-1,2,4-thiadiazol-2-yl)ethyl sulfide (BPTES), caudatan A might be the potential candidate as the inhibitor of KGA for further studies. [ABSTRACT FROM AUTHOR]

Abstract: The kinetics of oxidation of diethyl sulfide (Et2S) is studied in aqueous solutions of hydrogen peroxide and sodium peroxoborate (Na2[В2(О2)2(ОН)4]) in the presence of bicarbonate ions by means of gas−liquid distribution. The kinetics is investigated in a broad range of pH. Data show that the oxidation of Et2S by sodium peroxoborate in the range of pH 6−12 is mediated by such reactive species as hydrogen peroxide, hydrogen peroxide anions, and mono (B(O2H)(OH)) and diperoxoborate (B(O2H)2(OH)) anions. The rate of Et2S oxidation increases in the presence of bicarbonate, due to the additional reaction pathways mediated by monoperoxocarbonate species. [ABSTRACT FROM AUTHOR]

Chemical warfare agents have been used to incapacitate, injure or kill people, in a context of war or terrorist attack. It has previously been shown that hair could trap the sulphur mustard simulants methyl salicylate and 2-chloroethyl ethyl sulphide. In order to investigate simulants persistency in hair after intense vapour exposure, their desorption kinetics were studied by using two complementary methods: hair residual content measurement and desorbed vapour monitoring. Results showed that both simulants were detected in air and could be recovered from hair 2 h after the end of exposure. Longer experiments with methyl salicylate showed that it could still be recovered from hair after 24 h. Our data were fitted with several kinetic models and best correlation was obtained with a bimodal first-order equation, suggesting a 2-step desorption kinetics model: initial fast regime followed by a slower desorption. 2-chloroethyl ethyl sulphide was also detected in the immediate environment after hair exposure for 2 h, and hair simulant content decreased by more than 80%. Our results showed that hair ability to release formerly trapped chemical toxics could lead to health hazard. Their persistency however confirmed the potentiality of hair analysis as a tool for chemical exposure assessment. [ABSTRACT FROM AUTHOR]

The major mononuclear aluminum species obtained in the reaction of aluminum atoms with dimethyl sulfide (DMS) and diethyl sulfide (DES), under cryogenic conditions, are the C-S insertion products, CH3AlSCH3 and CH3CH2AlSCH2CH3, respectively, showing that aluminum atoms can activate C-S bonds. The magnetic parameters were extracted from the EPR spectrum. Support for the spectral assignment was obtained by repeating the experiments with 13C-labeled dimethyl sulfide yielding 13CH3AlS13CH3. DFT calculations using the M06 functional have proven to be effective in predicting the isotropic and anisotropic Al hyperfine interaction values of the aluminum atom C-S insertion products. In addition, the thioalkyl radicals, CH3SCH2• and CH3CH2SCH•CH3 were formed in the aluminum atom reaction. [ABSTRACT FROM AUTHOR]

The synthesis of bis( ortho -tolyl)platinum(II) compounds containing diethyl sulfide ligands from [PtCl 2 (SEt 2 ) 2 ] and ortho -tolyl-lithium is presented. Formation of a dimer [Pt(4-MeC 6 H 4 ) 2 (μ-SEt 2 )] 2 is evidenced by 1 H NMR and HR-MS-ESI(+) spectra and the monomer trans - anti -[Pt(2-MeC 6 H 4 ) 2 (SEt 2 ) 2 ] is characterized by X-ray diffraction analyses. Theoretical studies indicate that dimerization of the most stable form of the monomer ( cis - syn ) to the most stable conformer of the dinuclear species (αββα) is favored (ΔE = −10.1 kJ/mol). The reactions of the dimer [Pt(4-MeC 6 H 4 ) 2 (μ-SEt 2 )] with imine ligands 4-ClC 6 H 4 CH = NCH 2 CH 2 NMe 2 and 2-Br,6-FC 6 H 3 CH = NCH 2 Ph gave a tridentate [C, N, N’] five-membered and a bidentate [C, N] seven-membered platinacycles, respectively. [ABSTRACT FROM AUTHOR]

Removal of chemical warfare agent (CWA) surrogates by highly porous carbon textiles was investigated. The carbon cloth was modified by oxidation in a mixture of concentrated sulfuric and nitric acid. This process did not affect textile structural integrity. The surface properties of the modified textiles were investigated, and their capabilities to remove 2-chloroethyl ethyl sulfide (CEES) and diethylsulfide (EES), two mustard gas surrogates, were evaluated. The oxidized carbon textiles have a highly active surface that has the ability to form radical species. This enhances the degradation of the surrogates, and so the detoxification efficiency. The reaction products detected suggest differences in degradation mechanisms which depend on the type of fabric surface features. Thus, the oxidized surfaces eliminate CEES mainly through dehydrohalogenation, while the nonoxidized surfaces act via hydrolysis. Only the oxidized carbon has a surface active enough to react with the less reactive surrogate EES, by cleavage of the C-S bond. The surface functional groups promote not only the radical formation but also contribute to a strong adsorption of the CWA surrogates, which enhance the decomposition of these toxic species. [ABSTRACT FROM AUTHOR]

This study reports the development of copper(I) thiocyanate (CuSCN) hole-transport layers (HTLs) processed from aqueous ammonia as a novel alternative to conventional n-alkyl sulfide solvents. Wide bandgap (3.4-3.9 eV) and ultrathin (3-5 nm) layers of CuSCN are formed when the aqueous CuSCN-ammine complex solution is spin-cast in air and annealed at 100 °C. X-ray photoelectron spectroscopy confirms the high compositional purity of the formed CuSCN layers, while the high-resolution valence band spectra agree with first-principles calculations. Study of the hole-transport properties using field-effect transistor measurements reveals that the aqueous-processed CuSCN layers exhibit a fivefold higher hole mobility than films processed from diethyl sulfide solutions with the maximum values approaching 0.1 cm2 V−1 s−1. A further interesting characteristic is the low surface roughness of the resulting CuSCN layers, which in the case of solar cells helps to planarize the indium tin oxide anode. Organic bulk heterojunction and planar organometal halide perovskite solar cells based on aqueous-processed CuSCN HTLs yield power conversion efficiency of 10.7% and 17.5%, respectively. Importantly, aqueous-processed CuSCN-based cells consistently outperform devices based on poly(3,4-ethylenedioxythiophene) polystyrene sulfonate HTLs. This is the first report on CuSCN films and devices processed via an aqueous-based synthetic route that is compatible with high-throughput manufacturing and paves the way for further developments. [ABSTRACT FROM AUTHOR]

Semiempirical methods pm6 and pm7 as well as density functional theory functionals exchange LSDA, exchange-correlation PW91 and PBE, hybrid B3LYP1 and PBE0 were compared for energy and geometry of thiophene, diethyl sulfide (DES) molecules and their binding to a frozen Ti(OH)(HO) complex having one coordinatively unsaturated Ti site representing small fragment of TiO anatase (001) surface. PBE0/6-31G(d) with DFT-D3 dispersion correction was the best method for description of thiophene and DES molecules geometries as comparison with experimental data demonstrated. Semiempirical methods pm6 and pm7 resulted in only three of four possible binding configurations of thiophene with the Ti(OH)(HO) complex while pm7 described correctly the enthalpy and all configurations of DES binding with the Ti(OH)(HO) complex. SBKJC pseudopotential and LSDA with and without dispersion correction produced flawed results for many configurations. PBE0 and PBE with and without dispersion correction and PW91 with 6-31G(d) basis set systematically produced dependable results for thiophene and DES binding to the Ti(OH)(HO) complex. PBE0-D3/6-31G(d), B3LYP1-D3/6-31G(d), and PBE-D3/6-31G(d) gave best match of binding energy for thiophene while PBE0/6-31G(d) gave best match of DES binding energy as comparison with CCSD(T) energy demonstrated. On the basis of the superior results obtained with PBE0/6-31G(d), it is the recommended method for modeling of adsorption over TiO surfaces. Such a conclusion is in agreement with recent literature. [ABSTRACT FROM AUTHOR]

Vapour phase catalytic degradation of diethyl sulfide (DES) (simulant of a potential chemical warfare agent: sulfur mustard) at higher concentration (∼1200 ppm) is carried out in a fixed bed flow reactor over Mn/zeolite-13X catalysts of different manganese contents. The reaction is studied in the temperature range of 60–180 °C using ozone as the oxidizing agent. The influence of various process parameters such as reaction temperature, metal content, gas hourly space velocities (GHSV), ozone-to-DES mole ratio and water vapor are studied for getting maximum activity of the catalysts. Results reveal that reaction temperature and water vapor has significant effect on the conversion of DES and stability of the catalyst. Higher ozone-to-DES mole ratio facilitates the complete mineralization of DES at mild reaction conditions. The major products identified in the gas phase degradation of DES are carbon oxides, ethylene, acetaldehyde, acetic acid, sulfur dioxide and diethyl sulfone. Traces of diethyl sulfoxide, ethanol, thioethanol, methane thiol, formic acid are also identified in GC-MS analyses. The plausible degradation pathway is proposed based on the products identified by analyses results. The Mn/zeolite-13X catalysts of different composition are prepared by wet impregnation method and characterized by different characterization techniques. [ABSTRACT FROM AUTHOR]

A palladium-catalyzed enantioselective reductive Heck reaction of enones using monodentate phosphoramidite ligands is described. α,α,α',α'-tetraaryl-1,3-dioxolane-4,5-dimethanol (TADDOL)-based phosphoramidites with palladium(II) acetate, and N-methyl dicyclohexylamine as reducing agent gives the reductive Heck product in high yields and enantioselectivities of up to 90 %. The solvent plays an important role and in diethyl carbonate, the chemo- and enantioselectivity appeared to be the highest. [ABSTRACT FROM AUTHOR]

The kinetics of diethyl sulfide (EtS) oxidation by aqueous sodium peroxoborate (Na[В(О)(ОН)]) solutions in a wide acidity range (from [HClO] = 1 mol/L to рН 12) has been studied using a kinetic distribution method. The kinetic data together with the results of B NMR spectroscopy demonstrate that the monoperoxoborate B(OH)(OH) and diperoxoborate B(OH)(OH) anions are the active species in EtS oxidation by sodium peroxoborate at рН 8-12. It is assumed that, at a high acidity of the medium ([HClO] = 0.05-1.0 mol/L), peroxoboric acid (ОН)ВООН or its protonated form (OH)BOOH are direct reactants along with НО and HOOH. [ABSTRACT FROM AUTHOR]

The effect of the addition of 5–100 ppm 2,3-butanedione, butanoic acid, methyl mercaptan, ethyl butanoate, diethyl sulfide, 3-methylbutanoic acid, acetaldehyde and ethanol on production of propanoic acid, acetic acid and 3-methylbutanoic acid in a Swiss cheese slurry system was investigated. Enumeration of propionic acid bacteria (PAB) was done to monitor the microbial count in the systems. A Swiss cheese slurry system was used to simulate cheese manufacturing based on accelerated ripening for a 6-day incubation period. The headspace concentrations of propanoic acid, acetic acid and 3-methylbutanoic acid were significantly decreased by the addition of 2,3-butanedione, butanoic acid, and methyl mercaptan, but were generally unaffected by ethyl butanoate, diethyl sulfide, 3-methylbutanoic acid, acetaldehyde and ethanol. Microbial enumeration also showed that there was a significant reduction of PAB in slurry systems with 100 ppm 2,3-butanedione, butanoic acid, and methyl mercaptan. [ABSTRACT FROM AUTHOR]

The synthesis and comparative analysis of catalytic properties of Cu- and Mo-containing ethylpropylimidazolium derivatives immobilized on silica-series mineral supports have been performed. The oxidation of diethyl sulfide and methyl phenyl sulfide with oxygen and hydrogen peroxide in a hydrocarbon medium has been studied as a model process. The catalyst based on ethylpropylimidazolium polymolybdates is the most active and stable in the oxidation of methyl phenyl sulfide. [ABSTRACT FROM AUTHOR]

A Pseudomonas sp. strain WL2 that is able to efficiently metabolize ethyl mercaptan (EM) into diethyl disulfide (DEDS) through enzymatic oxidation was isolated from the activated sludge of a pharmaceutical wastewater plant. One hundred percent removal of 113.5 mg L EM and 110.3 mg L DEDS were obtained within 14 and 32 h, respectively. A putative EM degradation pathway that involved the catabolism via DEDS was proposed, which indicated DEDS were further mineralized into carbon dioxide (CO), bacterial cells, and sulfate (SO) through the transformation of element sulfur and ethyl aldehyde. Degradation kinetics for EM and DEDS with different initial concentrations by strain WL2 were evaluated using Haldane-Andrews model with maximum specific degradation rates of 3.13 and 1.33 g g h, respectively, and maximum degradation rate constants of 0.522 and 0.175 h using pseudo-first-order kinetic model were obtained. Results obtained that aerobic degradation of EM by strain WL2 was more efficient than those from previous studies. Substrate range studies of strain WL2 demonstrated its ability to degrade several mercaptans, disulfides, aldehydes, and methanol. All the results obtained highlight the potential of strain WL2 for the use in the biodegradation of volatile organic sulfur compounds (VOSCs). [ABSTRACT FROM AUTHOR]

Superfine FeOOH powder in an aerosol state with a particle size of about 3 nm has been studied in the processes of reactive adsorption and photocatalytic oxidation of acetone and diethyl sulfide vapors in air. The aerosol (5 g) is sprayed with a Helmholtz resonator placed into the center of a 100-L plastic chamber. Spraying is completed in 2 min, and the aerosol settles down within a time of less than 5 min. Rapid partial adsorption of acetone and diethyl sulfide on aerosol nanoparticles with characteristic times of 1 and 1.3 min, respectively, has been observed. FeOOH exhibits no photocatalytic activity with respect to acetone oxidation. Diethyl sulfide is oxidized with the formation of acetaldehyde as an intermediate product and CO and CO as the final products. [ABSTRACT FROM AUTHOR]

Composite TiO2/activated carbon (TiO2/AC) and TiO2/SiO2 photocatalysts with TiO2 contents in the 10 to 80 wt. % range were synthesized by the TiOSO4 thermal hydrolysis method and characterized by AES, BET, X-ray diffraction and FT-IR ATR methods. All TiO2 samples were in the anatase form, with a primary crystallite size of about 11 nm. The photocatalytic activities of the TiO2/AC and TiO2/SiO2 samples were tested in the gas-phase photocatalytic oxidation (PCO) reaction of diethyl sulfide (DES) vapor in a static reactor by the FT-IR in situ method. Acetaldehyde, formic acid, ethylene and SO2 were registered as the intermediate products which finally were completely oxidized to the final oxidation products - H2O, CO2, CO and SO42- ions. The influence of the support on the kinetics of DES PCO and on the TiO2/AC and TiO2/SiO2 samples' stability during three long-term DES PCO cycles was investigated. The highest PCO rate was observed for TiO2/SiO2 photocatalysts. To evaluate the activity of photocatalysts the turnover frequency values (TOF) were calculated for three photocatalysts (TiO2, TiO2/AC and TiO2/SiO2) for the same amount of mineralized DES. It was demonstrated that the TOF value for composite TiO2/SiO2 photocatalysts was 3.5 times higher than for pure TiO2. [ABSTRACT FROM AUTHOR]

Highlights: [•] Durian sulphides act on TRPA1 stronger than TRPV1. [•] Durian contains a sufficient amounts of sulphides to activate TRP channels. [•] The main TRPA1 agonist in durian pulp is diethyl disulphide. [•] The body-warming effect of durian may be given by TRPA1 activation with its sulphides. [Copyright &y& Elsevier]

Polycrystalline Cu2ZnSnS4 films were prepared by thermal treatment of stacked Sn/Zn/Cu metallic precursors in the presence of diethyl sulfide, which is a less hazardous sulfur source than H2S gas. The effect of the hydrogen partial pressure on the crystal phases present in the films was investigated. It was found that sulfur and carbon atoms play an important role in film growth. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

The products formed in the gas-phase reactions of Cl atoms with (CH3CH2)2S and CH3CH2SCH3 have been investigated in a large volume reactor in NOx-free air at atmospheric pressure and (298 ± 2) K using long path “in situ” FTIR spectroscopy for the analysis. HCl, SO2 and CH3CHO were identified as the major products for both reactions. For the Cl + CH3CH2SCH3 reaction HCHO was also identified as a major product. The yields of the products obtained for the reaction of Cl with (CH3CH2)2S were (59 ± 2) %, (52 ± 5) % and (103 ± 4) % for HCl, SO2 and CH3CHO, respectively. For the reaction of Cl with CH3CH2SCH3 yields of (43 ± 5) %, (55 ± 3) %, (58 ± 3) % and (53 ± 5) % were obtained for HCl, SO2, CH3CHO and HCHO, respectively. This is the first products and mechanistic study for the gas-phase Cl-initiated oxidation of non-CH3SCH3 alkyl sulfides. Comparison with previous results for the reaction of Cl with dimethyl sulfide is made and simple atmospheric degradation mechanisms are postulated to explain the formation of the observed products. [ABSTRACT FROM AUTHOR]

[Display omitted] • The competitive adsorption mechanism of thiophene/diethyl sulfide was proposed. • The whole adsorption process with total loading increasing was described clearly. • The immanent reasons of transformation of competitive adsorption mechanism was found. • The effect of three practical factors on adsorption behavior was investigated. In order to study the competitive adsorption relationship between sulfides in the adsorption desulfurization (ADS) process, as the loads increase gradually to saturation adsorption, the competitive adsorption mechanism of thiophene /diethyl sulfide on the all-silicon Y zeolite was investigated by GCMC simulation for the first time. A two-stage loads dependence adsorption mechanism was acquired which can be named "optimization-displacement adsorption" and "relocation-displacement adsorption" with an inflection point of 36 molecule/UC. At the "optimization-displacement adsorption" stage, both thiophene and diethyl sulfide molecules could occupy the optimization adsorption site ideally in the initial phase and the thiophene molecules on the S sites (refers to other sites except for W sites in the supercages) would be displaced by the diethyl sulfide ones and migrated to the W (refers to the 12-members ring connecting the supercages site) when the total loads approached the inflection point. At "relocation-displacement adsorption", the thiophene molecules on the S site would be displaced by the diethyl sulfide ones and migrated to the W sites sequentially. Meanwhile, more and more proportions of the latter diethyl sulfide molecules are adsorbed away from the center of the supercage. This transformation of the competitive adsorption mechanism was proved to be related to the interaction energy. Besides, three more realistic factors on the adsorption behavior were investigated respectively. It was concluded that high temperature is conducive to enhancing the selectivity of thiophene adsorption, but lower temperature can remove the sulfide more completely. Cations may improve the selectivity of sulfide ether. Besides, mercaptan has a great effect on the adsorption of other sulfides. [ABSTRACT FROM AUTHOR]

Abstract: Artificial solar light responsive high surface area WO3-modified TiO2 nanotubes have been efficiently used for performing the gas phase photocatalytic degradation of diethylsulfide, taken as simulant for the live yperite Chemical Warfare blister Agent, known as mustard gas. They were prepared by impregnating hydrothermally-synthesized titanate nanotubes with tungstate salt prior to the final calcination step. The influence of the WO3 content, the inlet diethylsulfide concentration and the relative humidity on the photocatalytic activity as a function of time on stream has been investigated in terms of DES removal efficiency and of deactivation behavior. Modification of TiO2 nanotubes with 4wt.% of WO3 enhanced the photocatalytic activity in terms of DES removal efficiency and of resistance to sulfate deactivation. Correlation between the surface species and the on-stream activity and behavior of the photocatalysts was proposed, as well as possible reaction mechanism pathways. [Copyright &y& Elsevier]

Abstract: TiO2 aerosol generated by a sonic method has been applied for fast purification of air from diethyl sulfide (DES) vapors inside a closed chamber. Two types of experiments modeling the possible real situations were conducted – (1) aerosol spraying without irradiation followed by UV irradiation after aerosol deposition and (2) aerosol spraying under UV irradiation. Adsorption of DES on TiO2 particles was complete and fastest at the lowest air relative humidity (RH) while photocatalytic oxidation was fastest at RH 37%. The minimal TiO2 aerosol surface area needed to remove from air one DES molecule is 2.3nm2 at the adsorption and 1.5nm2 at the photocatalytic oxidation. The quantum efficiency of the DES consumption increases from 4.7 to 20% when the initial DES concentration increases from 100 to 1000ppm. The overall quantum efficiency of the DES deep oxidation reached 41 and 58% for the initial concentration 100 and 1000ppm, respectively. The results demonstrate unusually high activity of TiO2 aerosol for the adsorption-photocatalytic air purification from DES. [Copyright &y& Elsevier]

A study of the effect of sodium silicate (Na2SiO3) on the kinetics of the oxidation of diethyl sulfide (Et2S) by hydrogen peroxide in aqueous solution in a broad pH range has shown that the active species in the pathway catalyzed by this silicate are peroxopolysilicate anions. We determined the peroxopolysilicate stability constant (1.4 L/mol) and rate constant of the reaction of this species with Et2S (0.15-0.3 L/mol·s). [ABSTRACT FROM AUTHOR]

Molecular dynamics computer simulations with the OPLS-AAand EncadS all-atom force fields have been performed for liquid bis(methylthio)methaneand diethyl sulfide. For bis(methylthio)methane, additional simulationsusing gas electron diffraction and ab initio bond length and bondangle parameters were also performed. Although there were small differencesbetween the structures provided by the different molecular dynamicssimulations of bis(methylthio)methane, the main conformer was foundto be the AG one (54%), followed by the G+G+one (31%) in all the calculations. This is in contrast with gasphase electron diffraction and ab initio calculations, where the mainconformer was G+G+(70%; beside that, 30% AGwas assumed). For diethyl sulfide, no experimental data was presentfor the gas phase and the different interatomic potential sets produceddifferent conformer ratios: applying OPLS-AA resulted in 51% AG and40% AA, while from EncadS the main conformer was G+G+, with an occurrence of 69.5% (AG was present with 29.6%).Comparing the MD calculated structure factors to results of X-raydiffraction experiments, some differences could be found at Q< 5 Å–1in all cases. For bis(methylthio)methane,the EncadS potential produced the X-ray structure factor with thesmallest difference to the experimental one, whereas for diethyl sulfidethe OPLS-AA parameter set proved to be the more successful. The EncadSforce field provided a better approximation to the experimental valueof the enthalpy of vaporization for bis(methylthio)methane; for diethylsulfide, the two different force fields gave similar results. [ABSTRACT FROM AUTHOR]

The kinetics of the oxidation of diethyl sulfide (EtS) by hydrogen peroxide catalyzed by boric acid was studied in various water-alcohol solutions. The rate constants of the reactions of EtS with HO, HOO, monoperoxo-B(OH)(OOH), and diperoxoborates B(OH)(OOH) were lower in HO/ROH solutions than in water. However, the significantly greater solubility of EtS provides for a greater rate for its oxidation (w = k[EtS]) in these mixed media. [ABSTRACT FROM AUTHOR]

Abstract: Gas-phase photocatalytic oxidation (PCO) and adsorption of diethyl sulfide and ethanol in a batch reactor using Cr-modified TiO2-loaded MCM-41 silica and commercial TiO2 as photocatalysts were studied with in situ FTIR method. Mesoporous molecular sieves MCM-41 modified with Cr were synthesized by hydrothermal method; Si:Cr atomic ratio was 80:1 or 20:1. Final deposition of 25% TiO2 was conducted by sol-gel method using titanium isopropoxide as a precursor. Adsorption measurements in a static reactor were used to estimate the Langmuir isotherm parameters (monolayer capacity and adsorption constant). Photooxidation experiments under UV irradiation demonstrated that TiO2 loading on Cr-MCM-41 improve its activity in diethyl sulfide removal but decelerated the CO2 formation. On the contrary, the rate of ethanol oxidation increased strongly as a result of TiO2 loading and the highest activity was observed for 25% TiO2/MCM-41 photocatalyst without chromium. Sulfate species were detected on the TiO2 surface after complete diethyl sulfide oxidation. Water and CO2 were identified as the final products whereas acetaldehyde and CO were identified as by-products of ethanol photocatalytic oxidation. Visible light activity was not detected for TiO2/MCM-41 and TiO2/Cr-MCM-41 photocatalysts in oxidation of gas phase diethyl sulfide and ethanol. [Copyright &y& Elsevier]

Abstract: Isothermal vapor–liquid equilibrium (VLE) of the following systems was measured with a recirculation still: diethyl sulfide+ethanol at 343.15K, diethyl sulfide+1-propanol at 358.15K, and diethyl sulfide+propyl acetate at 363.15K. Diethyl sulfide+ethanol at 343.15K and diethyl sulfide+1-propanol at 358.15K systems exhibit positive deviation from Raoult''s law, whereas diethyl sulfide+propyl acetate at 363.15K system exhibits only slight positive deviation from Raoult''s law. A maximum pressure azeotrope was found in the systems diethyl sulfide+ethanol (x 1 =0.372, P =88.4kPa, T =343.15K) and diethyl sulfide+1-propanol (x 1 =0.640, P =96.8kPa, T =358.15K). No azeotropic behavior was found in diethyl sulfide+propyl acetate system at 363.15K. The experimental results were correlated with the Wilson model and compared to COSMO-SAC predictive model. Liquid and vapor phase compositions were determined with gas chromatography. All measured data sets passed the thermodynamic consistency tests. The activity coefficients at infinite dilution are also presented. [Copyright &y& Elsevier]

It was found that in a wide range of pH in the presence of boric acid the oxidation of diethyl sulfide (EtS) with hydrogen peroxide in an i-PrOH–HO medium occurs with the participation of HO, HOO, monoperoxo-(B(OH)OOH), and diperoxoborates (B(OH)(OOH)). The stability constants of peroxoborates and the rate constants for the reactions of HO, HOO, B(OH)(OOH), and B(OH)(OOH) with EtS under these conditions were determined. [ABSTRACT FROM AUTHOR]

The rate constant for the reaction of diethyl sulfide (DES; C2H5SC2H5) with ozone was determined for the first time, which was (2.77±0.27)×10−19 cm3 molecule−1 s−1 under a room temperature of (289±1)K. Experiments were conducted under supposedly pseudo-first-order decay conditions, keeping [DES]0>50[O3]0, but having different combinations of [DES]0 and [O3]0. Cyclohexane was added into the reactor to eliminate the effect of OH radicals. The wall decay of ozone and the role of cyclohexane were also discussed in the present work. [Copyright &y& Elsevier]

Abstract: Isothermal vapor–liquid equilibrium (VLE) for diethyl sulfide+cyclohexane were measured at 353.15 and 343.15K and diethyl sulfide+2-ethoxy-2-methylpropane were measured at 343.15 and 333.15K with a circulation still. All systems exhibit slight positive deviation from ideality. No azeotropic behavior was found in any of the systems studied. The experimental results were correlated with the Wilson model with temperature dependent parameters and also compared with the original UNIFAC, and the COSMO-RS predictive models. The measured diethyl sulfide+cyclohexane VLE have been used simultaneously with the excess enthalpy from literature for a correlation of temperature-dependent Wilson parameters. Excess molar enthalpies at 298.15K for diethyl sulfide+2-ethoxy-2-methylpropane system were calculated from the VLE data. Analyses of liquid and vapor-phase composition were determined with gas chromatography. All VLE measurements passed the used thermodynamic consistency tests (integral, infinite dilution and point test). [Copyright &y& Elsevier]

Data obtained for the kinetics of oxidation of diethyl sulfide (Et2S) by hydrogen peroxide in aqueous solution catalyzed by boric acid indicate that monoperoxoborates B(O2H)(OH) and diperoxoborates B(O2H)2(OH) are the active species. The rates of the reactions of Et2S with B(O2H)(OH) and B(O2H)2(OH) are 2.5 and 100 times greater than with H2O2. [ABSTRACT FROM AUTHOR]