China
Africa
Explore chapters and articles related to this topic
General Princlpes
Published in Martin B., S.Z., of Industrial Hygiene, 2018
Organosulfur compounds are very often noted for their “rotten egg” or garlic odors. Methanethiol, an example of thiols and thioethers, is used as a leak-detecting additive for methane, propane, and butane. Two examples of nitrogen-containing organosulfur compounds are thiourea and phenylthio-urea. These compounds are used as rodenticides but are also highly toxic to humans. Dimethylsulfoxide (DSMO) and sulfolane are examples of sulfoxides and sulfones. DSMO has a number of uses including as a paint and varnish remover and as a biological anti-inflammatory. Sulfolane is used as part of the BTX process where it helps in the extraction of benzene, toluene, and xylene from alkanes. Organic esters of sulfuric acids include methyl-sulfuric and ethylsulfuric acids, which are strong irritants.
INDUSTRIAL ORGANIC SOLVENTS
Published in Nicholas P. Cheremisinoff, Industrial Solvents Handbook, Revised And Expanded, 2003
Sulfolane, another highly polar solvent, is used to separate aromatic hydrocarbons from aliphatic hydrocarbons. The extraction process first developed by Shell Oil in 1959 and which is referred to as the "Sulfolane* process is used worldwide. The solvency of sulfolane for certain fatty acids and fatty acid esters is the basis for upgrading animal and vegetable fatty acids used in food products, paints, plastics, resins, and soaps. Aqueous solutions containing 30-70 wt% sulfolane are used to remove lignin from wood chips. Sulfolane is used to remove acidic components like hydrogen sulfide and carbon dioxide from gas feed stocks. Sulfolane is used as a polymerization solvent for the production of poly sulfones, polysiloxanes, polyphenylene ethers, and other polymers. Sulfolane is said to increase the reaction rates, afford easier polymer purification, and improved thermal stability. Sulfolane is a solvent for dissolving a variety of polymers for use in the fiberspinning process. Cellulose and cellulose ester polymers can be plasticized with sulfolane to give improved flexibility and other physical property improvements. Other application areas that have used sulfolane include electronic and electrical uses, textile dye uses, curing of polysulfide sealant, and as a catalyst in certain synthetic reactions.
P
Published in Joseph C. Salamone, Polymeric Materials Encyclopedia, 2020
In principle, poly(p-phenylene sulfone) might be produced by oxidizing poly(p-phenylene sulfide) (PPS, sold as Ryton™ by Phillips Petroleum Co.) (see Scheme V). The oxidation of sulfides is the most common procedure for the synthesis of low molar mass sulfones. However, one of the strong points of PPS is its chemical resistance. PPS is highly crystalline and therefore insoluble, and chemical reagents cannot easily penetrate the solid. Attempted oxidation of PPS does not produce poly(p-phenylene sulfone) but instead slowly crosslinks the polymer.6
Oxovanadium and dioxomolybdenum complexes: synthesis, crystal structure, spectroscopic characterization and applications as homogeneous catalysts in sulfoxidation
Published in Journal of Coordination Chemistry, 2021
Hadi Kargar, Azar Kaka-Naeini, Mehdi Fallah-Mehrjardi, Reza Behjatmanesh-Ardakani, Hadi Amiri Rudbari, Khurram Shahzad Munawar
After optimizing the reaction conditions, various aliphatic and aromatic sulfides were oxidized by this catalytic system to get corresponding sulfoxides and sulfones. Table 11 shows that most sulfides were completely converted into their products. In many cases, two different reaction times are reported as time taken by [VO(L)(OCH3)]n was less than that of [MoO2(L)(CH3OH)]. Also, higher selectivity was observed for vanadium catalyst for the sulfoxide formation over the sulfone. Initially sulfoxides were produced which were gradually converted into sulfones on increasing the reaction time.
Solid-state rearrangement of sandwich-type polyoxometalate-dopamine nanohybrid to the nanoflower Keggin polyoxometalate: synthesis, characterization, and catalytic efficiency
Published in Journal of Coordination Chemistry, 2020
Soleiman Fazeli Pirdosti, Roushan Khoshnavazi, Elham Naseri
Sulfoxides and sulfones are widely utilized as anti-bacterial, anti-fungal, anti-atherosclerotic, anti-ulcer, vasodilators and cardiotonic agents and as well as for activation of enzymes. Traditional preparations with stoichiometric amounts of electrophilic reagents such as peracids, dioxiranes, hypochlorites, periodates, and highly toxic oxometal oxidants usually are accompanied by disadvantages such as long reaction times, low yields, inconvenient reaction conditions, environmentally unfavorable catalysts and the formation of toxic wastes [31,32].