Sulfonic acids from sulfur compounds

ASR-2 A process for desulfurizing diesel fuel by oxidation with hydrogen peroxide and formic acid. The sulfur compounds are oxidized to sulfones that are removed by adsorption on alumina. Developed by Unipure and Texaco and demonstrated at Valero Energy s refinery at Krotz Spring, LA, from 2002. 

Sulfonic acids can come from the sulfonation of oil cuts from white oil production by sulfuric acid treatment. Sodium salts of alkylaromatic sulfonic acids are compounds whose aliphatic chains contain around 20 carbon atoms. The aromatic ring compounds are mixtures of benzene and naphthalene rings. 

Other direct methods for the sulfonation of the higher fatty acids are by the use of sulfur trioxide vapor or by the use of chlorosulfonic acid. Indirect methods are also available for the preparation of a-sulfo fatty acids and their salts from an a-bromo fatty acid made by the Hell-Volhard-Zelinsky reaction. The bromo compound may be converted directly to the sodium salt of a sulfonic acid through the Strecker reaction or may be converted to the mercaptan and oxidized to the sulfonate. Sulfonation of the lower fatty acids has been studied by Backer and co-workers. ... 

Desulfurization using purified enzymes Investigations into enzymatic desulfurization as an alternative to microbial desulfurization has revealed several enzymes capable of the initial oxidation of sulfur. A study reported use of laccase with azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as a mediator for oxidation of DBT [181]. The rate of this reaction was compared to hydrogen peroxide-based phosphotungstic acid-catalyzed oxidation and the latter was found to be about two orders of magnitude higher. The authors also oxidized diesel oil sulfur to no detectable levels via extraction of the oxidized sulfur compounds from diesel. In Table 9, the enzymes used in oxidation of DBT to DBTO are reported. 

Simultaneously with Hansa Yellow G, compound 84 was first described as early as 1909 by Farbenfabriken Bayer. Its preparation starts from l-amino-4-bro-moanthraquinone-2-sulfonic acid (bromamine acid) 85. Dimerization is achieved through the Ullmann reaction, i.e., treatment with fine-grain copper powder in dilute sulfuric acid at 75°C. The separated intermediate, the disodium salt of 4,4 -diamino-l,l -dianthraquinonyl-3,3 -disulfonic acid 86, is heated to 135 to 140°C in the presence of 80% sulfuric acid in order to cleave the sulfonic acid groups [7] ... 

In ODS, sulfur compounds present in fuels are oxidized to more polar sulfones / sulfoxides to facilitate their removal by solvent extraction or adsorption. Various oxidation systems have been reported in the literature for this transformation. Among these oxidants like hydrogen peroxide (H2O2) and carboxylic acid as catalyst3"5. For the chemical industry, it becomes more and more important to develop cleaner technologies. Solvent extraction processes are used to separate sulfones / sulfoxides from oxidized fuels. These processes required suitable and selective solvents for separation of oxidized sulfur compounds from petroleum feedstocks. 

Although no conclusive evidence has been reported so far, the possible importance of organic sulfur species as sulfate aerosol precursors is supported by several observations. Sulfuric acids, sulfonic acids, and other organic sulfur compounds are formed in sulfur dioxide-hydrocarbon reactions at high concentrations. Organosulfiir radical species, such as RSO2 and RO2SO2 have been postulated as intermediates for these reactions. Suzuki (see Penzhom et o/. ) observed polymer formation from... 

Rajagopal et al. (1984) used numerous compounds to develop a proposed pathway of degradation of aldicarb in soil. These compounds included aldicarb oxime, A-hydroxymethyl aldicarb, A-hydroxymethyl aldicarb sulfoxide, A-demethyl aldicarb sulfoxide, A-demethyl aldicarb sulfone, aldicarb sulfoxide, aldicarb sulfone, A-hydroxymethyl aldicarb sulfone, aldicarb oxime sulfone, aldicarb sulfone aldehyde, aldicarb sulfone alcohol, aldicarb nitrile sulfone, aldicarb sulfone amide, aldicarb sulfone acid, aldicarb oxime sulfoxide, aldicarb sulfoxide aldehyde, aldicarb sulfoxide alcohol, aldicarb nitrile sulfoxide, aldicarb sulfoxide amide, aldicarb sulfoxide acid, elemental sulfur, carbon dioxide, and water. Mineralization was more rapid in aerobic surface soils than in either aerobic or anaerobic subsurface soils. In surface soils (30 cm depth) under aerobic conditions, half-lives ranged from 20 to 361 d. In subsurface soils (20 and 183 cm depths), half-lives under aerobic and anaerobic conditions were 131-233 and 223-1,130 d, respectively (Ou et al, 1985). The reported half-lives in soil ranged from approximately 70 d (Jury et ah, 1987) to several months (Jones et al, 1986). Bromilow et al. (1980) reported the half-life for aldicarb in soil to be 9.9 d at 15 °C and pH 6.34-7.0. 

Resonance energies have been reported164 (see also ref. 154a) for a few conjugated sulfur compounds thiolacetic acid (4-5 kcalmole-1), thiourea (27 kcalmole-1), thiosemicarbazide (28 kcalmole-1), thiophene (20 kcalmole-1), and thianthrene (17 kcalmole-1 difference between the resonance energy of thianthrene and that of two benzene molecules). These values were calculated from the heats of combustion and bond energies, which are 61.5 kcal for the C—S, 115 kcal for the C=S, 87.5 kcal for the S—H, and 67 kcal for the S—S bonds.156 Calorimetry of sulfones has been studied intensively.156... 

Addition products have been obtained from aminochrome derivatives such as the semicarbazone, with sodium bisulfite. Recently Correia Alves reported the preparation of a compound described as adrenochrome semicarbazone sodium sulfonate (m.p. >300°) by treating a solution of adrenochrome monosemicarbazone (90) in sodium carbonate solution with sulfur dioxide at 40° for several days192 this compound was apparently different from the substance (m.p. 227-228°) obtained in a somewhat similar manner by Iwao193-194 and may be comparable to the compound (83) (m.p. > 300°) previously described in a Belgian patent179 (see Section IV,F). Iwao established the structure of his compound as the sodium salt of epinochrome-3-sulfonic acid monosemicarbazone (93).193... 

The acetaldehyde-sulfurous acid compound has the properties of a sulfonic acid with C-S linkage rather than an ester structure as once assumed. It is properly 1-hydroxyethane sulfonic acid (23, 24) and is highly acidic (25). Samples of concentrated heads from commercial aldehyde columns having aldehyde contents of 5-13% gave pH values of 0.7-0.9 and contained high levels of copper (25). 

Sulfur compounds I, II and IV, methyl sulfonic acid, ethylsulfonic acid and benzenesulfonic acid could have been derived from a number of precursors in the parent coal samples. Firstly, mercaptans and thiols will form sulfonic acids when oxidized with peroxides. However, the presence of methylmercaptan, ethylmercaptan and benzenethiol in an exhaustively extracted coal sample is highly unlikely and we believe that the sulfonic acids did not arise from these compounds. In addition, there is a possibility that these sulfonic acids may have come from pendant or terminal thioether groups. 

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