Decomposition Of Dimethyl Sulfoxide Research Articles

Development of a flow photocatalytic reactor for the photodecomposition of Ga(III) complexes and recovery of free Ga(III) radioisotopes

This report describes the development and application of a flow photocatalytic reactor for the effective photodecomposition of organic compounds and the recovery of a targeted metal ion; specifically, we describe the decomposition of a gallium-ethylenediaminetetraacetic acid (Ga-EDTA) complex. The system includes a scrubber, which increases the amount of dissolved oxygen in the solution before entering the photocatalytic reactor. First, the decomposition efficiency of the developed reactor is evaluated using dimethyl sulfoxide (DMSO). The decomposition of DMSO is accelerated upon introducing oxygen from the scrubber into the flowline. Second, we employ this system for the decomposition of Ga-EDTA and evaluate the recovery of a Ga radioisotope (RI), which can serve as a probe in positron emission tomography for medical diagnoses. The byproducts generated during Ga-EDTA photodecomposition are monitored by capillary electrophoresis, and the released Ga3+ concentrations are determined by inductively coupled plasma atomic emission spectroscopy for the stable isotope of Ga and with a scintillation detector for RI-Ga. After 30 min under ultraviolet irradiation, 54 % of the RI-Ga released during the photodecomposition of RI-Ga-EDTA was recovered.

Synthesis and electrochemical properties of sulfur-nitrogen-doped multi-walled carbon nanotubes

Multi-walled carbon nanotubes doped with sulfur and nitrogen (S-N-MWCNTs) were grown onto silicon/silicon oxide wafer by means of chemical vapor deposition upon decomposition of dimethyl sulfoxide (DMSO) and acetonitrile (ACN) in presence of catalyst. The S-N-MWCNTs were characterized by scanning electron microscopy combined with energy dispersive X-ray spectroscopy. The findings demonstrate that S-N-MWCNTs exhibit bamboo-shaped nanostructure, quite similar to pure nitrogen-doped carbon nanotubes. The S-N-MWCNTs were investigated with respect to their electrochemical response to ferrocyanide/ferricyanide, [Fe(CN)6]4-/3- in potassium chloride aqueous solutions by means of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques. The recorded CVs demonstrate strong dependence of electrochemical response, electron transfer kinetics, and sensitivity of S-N-MWCNTs on concentration of decomposed DMSO precursor. Namely, upon increasing concentration of decayed DMSO up to 2% wt. the current density, the electron transfer kinetics, and the sensitivity of S-N-MWCNTs toward [Fe(CN)6]4-/3- tend to enhance. The extracted EIS results approve that when DMSO reaches the optimum concentration of 2% wt. the barrier for electron transfer decreases significantly leading, consequently, to faster electron transfer kinetics. The S-N-MWCNTs exhibit considerable stability and excellent reproducibility, and thus it can be considered suitable analytical tool for detection of redox systems at micromolar level.

Effect of Zinc Oxide on the Thermal Decomposition of Dimethyl Sulfoxide

Effect of Zinc Oxide on the Thermal Decomposition of Dimethyl Sulfoxide

Study on Autocatalytic Decomposition of Dimethyl Sulfoxide (DMSO) III: Investigations Regarding the Main Decomposition

It is important to know the entire decomposition mechanism of energetic materials for safety purposes, such as the assessment, control, mitigation, and prevention of thermal hazards. Dimethyl sulfoxide (DMSO) is a common solvent that is widely used in laboratories and industrial applications; however, several severe incidents due to its decomposition have been reported. The decomposition mechanism of DMSO has been studied for several years; however, it has not been sufficiently clear until now. To elucidate the complicated decomposition pathway, analyses of materials from DMSO decomposition were conducted. Several new chemical bonds were found in the decomposition products through gas chromatography–mass spectrometry (GC-MS) analysis, which suggests a radical reaction. Atomic sulfur S(0) or organic divalent sulfur S(II) was found on the inner wall of the vessel after decomposition, which indicates that the sulfur atom in DMSO was reduced during decomposition. In addition to the chemical analyses, a kinetic study was carried out for the data obtained through isothermal heating tests. All of the DMSO samples with or without the studied impurities showed similar activation energies for the main decomposition. Autocatalysts in DMSO decomposition are proposed to work not by accelerating the main decomposition but rather by shortening the induction period. It is proposed that the main decomposition of DMSO occurs via a radical pathway.

Study on Autocatalytic Decomposition of Dimethyl Sulfoxide (DMSO) II: Analysis of Intermediate Substances Obtained in the Induction Period and Investigations Regarding Formic Acid

Dimethyl sulfoxide (DMSO) is a good solvent as well as a mild oxidizing agent. Several severe incidents associated with DMSO decomposition have been reported in spite of its wide use. The goal of t...

Development of evaluation method for photocatalytic ability by ion chromatography combined with a flow-type reactor: Application to immobilized photocatalyst materials prepared by double-layer coating method

In this study, an inline method to effectively utilize photocatalytic materials for water-purification, comprising a flow reactor (FR) connected to an ion chromatography (IC) system, denoted as FR-IC, has been developed to accurately evaluate the performance of photocatalyst-coated substrates. This system is essential for determining not only indicator decomposition, but also byproduct behavior. Small portions (30 μL) of the 50-mL test solution were collected from the FR using a flow cell input and automatically injected into the IC for chromatographic analysis at regular intervals. The stable photocatalytic ability of materials comprising TiO2 photocatalyst coated onto substrates, such as glass beads, glass plate, and stainless-steel wire mesh, have also been demonstrated using the FR-IC system. These materials were prepared using the double-layer coating (DLC) method developed in our laboratory. The performances of these materials were evaluated by FR-IC using dimethyl sulfoxide (DMSO) as the radical scavenger and index pollutant. FR-IC enabled monitoring of the UV-light-induced decomposition of DMSO and the formation of byproducts, such as methane sulfonate (MSO) and sulfate (SA). Durability testing of the photocatalyst substrates prepared by the DLC method over ten repeat cycles of MSO formation from DMSO decomposition showed stable reactions, compared with a TiO2 monolayer-coated substrate. These materials showed stable photoactivity for water purification. Furthermore, this system showed that the substrate-immobilized photocatalyst adsorbed the derivatives during UV irradiation. Therefore, the selection of substrate coated with the photocatalyst was related to the water purification performance.

Observation of the intercalation of dimethyl sulfoxide-solvated lithium ion into graphite and decomposition of the ternary graphite intercalation compound using in situ Raman spectroscopy

Dimethyl sulfoxide (DMSO) is electrochemically co-intercalated with lithium ions into graphite to form a stable ternary graphite-intercalation-compound (GIC), Li-DMSO-GIC. To elucidate the details of the co-intercalation behavior, in situ Raman spectroscopy was performed to observe the structural variations in graphite during the potential scan. During the scan from 2.44 to 1.00 V, DMSO was co-intercalated with lithium ions into graphite, exhibiting a staged structure. The stage number decreased from 4 to 1. During the scan from 1.00 to 2.44 V, the deintercalation of DMSO-solvated lithium ions was observed. After experienced a potential cycle between 2.4 and 0 V, the graphite exhibited significant changes that are ascribed to the exfoliation of graphite, implying that the destruction of the graphite composite electrode is likely to be caused by the decomposition of DMSO within the graphite layer.

Insights into dimethyl sulfoxide decomposition in Li-O2 battery: Understanding carbon dioxide evolution

DMSO has been widely investigated as a potential electrolyte for the Li-air battery systems, however its stability has been a topic of debate in the research community. In this communication we have identified the side reaction products during the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) on Au in dimethyl sulfoxide-based electrolyte for Li-air battery by a combination of in-situ analytical tools: EQCM, SNIFTIRS, DEMS and XPS, in particular the evolution of CO2 from the solvent decomposition.

Chemical Instability of Dimethyl Sulfoxide in Lithium-Air Batteries.

Although dimethyl sulfoxide (DMSO) has emerged as a promising solvent for Li-air batteries, enabling reversible oxygen reduction and evolution (2Li + O2 ⇔ Li2O2), DMSO is well known to react with superoxide-like species, which are intermediates in the Li-O2 reaction, and LiOH has been detected upon discharge in addition to Li2O2. Here we show that toroidal Li2O2 particles formed upon discharge gradually convert into flake-like LiOH particles upon prolonged exposure to a DMSO-based electrolyte, and the amount of LiOH detectable increases with increasing rest time in the electrolyte. Such time-dependent electrode changes upon and after discharge are not typically monitored and can explain vastly different amounts of Li2O2 and LiOH reported in oxygen cathodes discharged in DMSO-based electrolytes. The formation of LiOH is attributable to the chemical reactivity of DMSO with Li2O2 and superoxide-like species, which is supported by our findings that commercial Li2O2 powder can decompose DMSO to DMSO2, and that the presence of KO2 accelerates both DMSO decomposition and conversion of Li2O2 into LiOH.

The catalytic role of tungsten electrode material in the plasmachemical activity of a pulsed corona discharge in water

The effects of tungsten material used as a high-voltage needle electrode on the production of hydrogen peroxide and the degradation of dimethylsulfoxide (DMSO) caused by a pulsed corona discharge in water were investigated. A reactor of needle–plate electrode geometry was used. The erosion of the tungsten electrodes by the discharge was evaluated. The yields of H2O2 production and the decomposition of DMSO by the discharge, which were obtained using the tungsten electrodes, were compared with those determined for titanium electrodes. The electrode erosion increased significantly with an increase in the solution conductivity. A large fraction (50–70%) of the eroded tungsten electrode material was released into the solution in dissolved form as tungstate ions. A correlation between the amount of eroded tungsten material released into the solution and the chemical effects induced by the discharge was determined. Lower yields of H2O2 and a higher degradation of DMSO by the discharge were obtained using the tungsten electrodes than were determined using titanium electrodes. Tungstate ions were shown to play a dominant role in the decomposition of H2O2, which was produced by the discharge using a tungsten electrode. The higher degradation of DMSO that was determined for tungsten was attributed to the tungstate-catalyzed oxidation of DMSO by H2O2, in addition to the oxidation of DMSO by OH radicals. Such a mechanism was supported by the detection of degradation by-products of DMSO (methanesulfonate, sulfate and dimethyl sulfone). The catalytic role of tungstate ions in the plasmachemical activity of the discharge generated using a tungsten electrode was also demonstrated on a pH-dependent decomposition of H2O2 and DMSO.

ChemInform Abstract: THERMOLYSIS OF DIMETHYL SULFOXIDE

Chemischer InformationsdienstVolume 4, Issue 42 Preparative Organic Chemistry ChemInform Abstract: THERMOLYSIS OF DIMETHYL SULFOXIDE F. C. THYRION, F. C. THYRIONSearch for more papers by this authorG. DEBECKER, G. DEBECKERSearch for more papers by this author F. C. THYRION, F. C. THYRIONSearch for more papers by this authorG. DEBECKER, G. DEBECKERSearch for more papers by this author First published: October 16, 1973 https://doi.org/10.1002/chin.197342134Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume4, Issue42October 16, 1973 RelatedInformation