Sulfur transformation

Sulfur Transformation during Sewage Transport (T. Hvitvedt-Jacobsen, P. H. Nielsen)... 

The third law of thermodynamics can be verified experimentally. The stable rhombic low-temperature modification of sulfur transforms to monoclinic sulfur at 368.5 K (p = 1 bar). At that temperature, Ttrs, the two polymorphs are in equilibrium and the standard molar Gibbs energies of the two modifications are equal. We therefore have... 

Strickland TC, Fitzgerald JW, Ash JT, Swank WT (1987) Organic Sulfur transformations and Sulfur Pool Sizes in Soil and Litter From A Southern Appalachian Hardwood Forest. Soil Sci 143 453-458... 

Reaction of 52 with benzyl chloride opens134 a new way to the deoxyhalo-genoisohexides (55). The oxidation of 52 with air or sulfur transforms the phosphinites into the phosphonates (56a) and thiophosphonates (56b), respectively (see Scheme 8). With 15% sodium hydroxide, the phosphonates... 

Figure 7. Sulfur transformations of seston-S and microbially reduced S in sediments of Little Rock Lake. This diagram is based on information collected from the lake (cores and sediment traps) and from laboratory sediment-water microcosms to which 35S was added as labeled algae or as 35S042 Sizes of circles and arrows are roughly proportional to magnitudes of pools and fluxes, respectively. ROSO3 = ester-S MeS = metal sulfide, C-S = carbon-bonded S.

The primary process by which sulfur is fractionated in hydrologic environments is via biologically mediated sulfur transformations. The most important of these is the dissimilatory sulfate reduction (DSR) reaction... 

Mayer B., Krouse H. R., Fritz P., Prietzel J., and Rehfuess K. E. (1993) Evaluation of biogeochemical sulfur transformations in forest soils by chemical and isotope data. In Tracers in Hydrology, lAHS Publ. No. 215, pp. 65 -72. 

The study of sulfur diagenesis has a long history. Scientists have long accepted that microorganisms play a major role in geochemical sulfur transformations (Baas Becking, 1925). They also recognized at an earlier time that removal of sulfate occurs in the pore waters of marine mud (Murry, 1895). Subsequent work established that depletion of sulfate from marine pore water is a... 

Visscher P. T. and Van den Ende F. (1994) Diel and spatial fluctuations of sulfur transformations. In Microbial Mats. Structure, Development, and Environmental Significance (eds. L. J. Stal and P. Caumette). Springer, Berlin, pp. 353-360. 

Box 7. Microbial sulfur transformation in the system hydrogen sulfide - sulfate -dimethyl sulfide (after Fenchel et al, 1998)... 

Hydrogen sulfide(HiS) production and consumption quantitatively dominate microbial sulfur transformation in marine ecosystems. However, in spite of relatively high rates of sulfate reduction in marine environments, gaseous fluxes of H2S are relatively small. This emission constraining is related to ... 

Microbial sulfur transformations in the system hydrogen sulfide-sulfate-dimethyl sulfide play the most important role. Compare the role of these transformations in terrestrial and aquatic ecosystems. 

The sea bed functions as a giant anaerobic reactor where element cycles are coupled in a way that differs fundamentally from the cycles in the oxic ocean. The microbiological and geochemical processes of sulfur transformation thereby play key... 

Krein, E.B. and Aizenshtat, Z., 1995. Proposed thermal pathways for sulfur transformations in organic macromolecules Laboratory simulation experiments. In Vairavamurthy, M.A. and Schoonen,... 

In more efficiently designed and operated sulfur burners such as those used in the paper industry and in the manufacture of sulfuric acid (Shreve, 1944), the sulfur is melted, atomized in compressed air, and burnt in a separate combustion chamber. In these burners gas of a constant composition, 19-20 volume per cent SOa, without any sublimation and with only 0.14% of the sulfur transformed into SOs, can be obtained. Sulfur dioxide is a colorless gas having a characteristic odor, a normal molecular volume of 21.89 1., and a molecular weight of 64.06 g. It is soluble to the extent of 36.4 volumes in one volume of water at 20° C. Its solubility in water decreases from 8.6% by weight at 20° C. to 0.1% at 100° C. At atmospheric pressure SO2 liquefies at —10° C. at 20° C. liquid SO2 exerts a pressure of 3.25 atm. or 40.6 p.s.i. The solubility of sulfur dioxide in water has been determined accurately by Beuschlein and... 

SAGGAR S., BETTANY J.R. and STEWART J.W.B. 1981. Sulfur transformations in relation to carbon and nitrogen in incubated soils. Soil Biology and Biochemistry, 33, 499-511. 

---