Dissolved organic sulfur

Dissolved organic sulfur was determined in aqueous solutions after isolation by solid-phase extraction on macroporous resins and reversed-phase sorbents.156 The sulfur in the extracts was determined by pyrohydrogenolysis of the extract in a heated quartz tube (1100°C) in a hydrogen atmosphere followed by flame photometric detection. 

Binde, F. and H.H. Riittinger. 1997. Isolation and determination of dissolved organic sulfur compounds— development of the organic group parameter DOS. Fresenius J. Anal. Chem. 357 411—415. 

DON, dissolved organic nitrogen DOS, dissolved organic sulfur Dt, diatoxanthin... 

Besides the analysis of individual substances, organic sulfur compounds are also analyzed as sum parameters. Examples include dissolved organic sulfur (DOS), adsorbable organic sulfur compounds (AOS), and ion-pair extractable sulfur compounds (lOS). 

Ruttinger, H. H. and Binde, F., Detemtination of the organic group parameters DOS (dissolved organic sulfur) in rivers and in the process of drinking water production, VomWasser,9Q, 1-8, 1998. 

After epoxidation, propylene oxide, excess propylene, and propane are distilled overhead. Propane is purged from the process propylene is recycled to the epoxidation reactor. The bottoms Hquid is treated with a base, such as sodium hydroxide, to neutralize the acids. Acids in this stream cause dehydration of the 1-phenylethanol to styrene. The styrene readily polymerizes under these conditions (177—179). Neutralization, along with water washing, allows phase separation such that the salts and molybdenum catalyst remain in the aqueous phase (179). Dissolved organics in the aqueous phase ate further recovered by treatment with sulfuric acid and phase separation. The organic phase is then distilled to recover 1-phenylethanol overhead. The heavy bottoms are burned for fuel (180,181). 

Certain refinery wastewater streams are treated separately, prior to the wastewater treatment plant, to remove contaminants that would not easily be treated after mixing with other wastewater. One such waste stream is the sour water drained from distillation reflux drums. Sour water contains dissolved hydrogen sulfide and other organic sulfur compounds and ammonia which are stripped in a tower with gas or steam before being discharged to the wastewater treatment plant. 

In addition, PhCH2SCH2Ph forms 1 1 adducts with Hg2(N03)2 and 1 2 adducts with Hg 2(0104)2. Two-phase systems can be used to isolate these complexes. The Hgd) salt is dissolved in H2O or MeOH, the organic sulfur ligand is dissolved in benzene or CH2CI2 and the two solutions are stirred together. 

Plummer invented a process for the biodesulfurization of hydrocarbons [157], in which organic sulfur compounds contained in liquid hydrocarbons are converted to elemental sulfur. The reaction is carried out in the presence of a biocatalyst and hydrogen, by dissolving completely the liquid hydrocarbons in an organic solvent, such as a nucleophilic and/or electrophilic solvent(s). The nucleophilic solvent should have a pKa greater than 2, and the electrophilic solvent more negative than -2. Recommended nucleophilic solvents include -butylamine, diethylamine, butanediamine, ethylenimine, toluene, pyridine, aniline, and acetophenone. The electrophilic solvents could be methylethylketone, pyrrole, or benzaldehyde. 

Sulfinol A process for removing hydrogen sulfide, carbon dioxide, carbonyl sulfide, and organic sulfur compounds from natural gas by scrubbing with di-isopropanolamine dissolved in a mixture of sulfolane and water. Developed in the 1960s by Shell International Research Mij N.V, The Netherlands and Shell Development Company, Houston. In 1996, over 180 commercial units were operating or under construction. 

Other methods start from crude indanthrone, which is dissolved in sulfuric acid or oleum (sometimes mixed with organic solvents). The product may be precipitated with water. It is more advantageous to separate the precipitated crude pigment, to reslurry it in water, and to heat the resulting aqueous suspension in the presence of a cationic surfactant. Subsequent treatment of the sulfuric acid solution with nitric acid, manganese dioxide, or chromium trioxide is followed by transfer into a solution containing sodium sulfite or iron(II)sulfate. 

When the metals were studied, the release of gases and vapors was observed. For example, Paracelsus reported that when iron was dissolved in sulfuric acid air comes out like a wind. The differentiation of these kinds of air took more than two centuries. Research on the analysis of gases was extremely productive in developing the basic methods to handle and study gases and even paved the way to design techniques for elementary analysis of the constituents of organisms. Thus the study of gases became the second epoch of analytical chemistry it is called the pneumatic age. ... 

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