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Journal articles on the topic 'Elemental sulphur oxidation'

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Published: 10 December 2022

Last updated: 29 January 2023

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1

Cowell, L. E., and J. J. Schoenau. "SHORT COMMUNICATION: Stimulation of elemental sulphur oxidation by sewage sludge." Canadian Journal of Soil Science 75, no. 2 (May 1, 1995): 247–49. http://dx.doi.org/10.4141/cjss95-035.

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Sewage sludge and elemental sulphur (S°) were combined and incubated under controlled conditions. Sulphur oxidation was enhanced by sewage sludge, though acidification of the mixtures prevented more than 4% of the S° from being converted to sulphate. When introduced to the soil environment, over 50% of the S° from these mixtures oxidized within 6 wk, compared with about 20% oxidation of S° applied without sewage sludge. Key words: Elemental sulphur, sulphur oxidation, sewage sludge

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2

Mandl, Martin, Eva Pakostova, and Lenka Poskerova. "Minimum Aeration in Acidithiobacillus ferrooxidans Cultures Required to Maintain Substrate Oxidation without Oxygen Limitation." Advanced Materials Research 825 (October 2013): 414–17. http://dx.doi.org/10.4028/www.scientific.net/amr.825.414.

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The volumetric oxygen transfer coefficient (kLa) was used to define the conditions necessary for minimum aeration and to eliminate potential oxygen limitation in bioleaching cultures ofAcidithiobacillus ferrooxidans. The Michaelis constants for oxygen were 1.07 and 0.71 μmol O2l-1for the oxidation of ferrous iron and elemental sulphur, respectively. The critical oxygen concentration, below which oxygen limitation occurred, was determined to be 6.25 and 3.125 μmol O2l-1for the oxidation of ferrous iron and elemental sulphur, respectively. The (kLa)critvalues required to maintain oxygen-unlimited substrate oxidation for ferrous iron and elemental sulphur were 7.70 and 4.88 h-1, respectively.

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3

Chapman, S. J. "Oxidation of micronized elemental sulphur in soil." Plant and Soil 116, no. 1 (May 1989): 69–76. http://dx.doi.org/10.1007/bf02327258.

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4

Laishley, E. J., R. D. Bryant, B. W. Kobryn, and J. B. Hyne. "Microcrystalline structure and surface area of elemental sulphur as factors influencing its oxidation by Thiobacillus albertis." Canadian Journal of Microbiology 32, no. 3 (March 1, 1986): 237–42. http://dx.doi.org/10.1139/m86-047.

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The effect of particle size, surface area per unit weight, and molecular composition of S0 on the rate of S0 oxidation by Thiobacillus albertis was studied. Spherical S0 prills varying in size and surface areas were prepared and added as the sulphur source to synthetic salts medium. The rate of S0 oxidation by T. albertis was found to be a function of surface area/unit weight of sulphur. In all these experiments [Formula: see text] was produced in a linear manner with time indicating sterically favorable cell–sulphur oxidation binding sites for bacterial growth. Different powdered forms of S0 (high-purity orthohombic, high-purity polymeric, and mixed molecular sulphur) were oxidized at a significantly faster rate than the prilled S0. Also the initial oxidation was exponential up to 3 days at which point [Formula: see text] production from mixed molecular sulphur utilization fell off substantially with time as compared with similar [Formula: see text] rate curves obtained with high-purity orthorhombic and high-purity polymeric oxidation. It was implied that the increased Sx content in mixed molecular sulphur was responsible for the slower oxidation rate by altering the sulphur crystal lattice formation which affected the number of sterically favorable oxidation binding sites for T. albertis growth. Thiobacillus albertis was shown to colonize S0 surfaces as microcolonies. It was concluded that particle size, surface area/unit weight, and the crystal microstructure of S0 affects the oxidation rate of S0 by T. albertis.

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5

Kurek, Ewa. "Elemental Sulphur and Thiosulphate Oxidation by Rhodotorula sp." Zentralblatt für Mikrobiologie 140, no. 6 (1985): 497–500. http://dx.doi.org/10.1016/s0232-4393(85)80056-1.

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6

Méndez, Manuel A., Alberto Cano, and Marco F. Suárez. "Sonophotocatalytic oxidation of elemental sulphur on titanium dioxide." Ultrasonics Sonochemistry 14, no. 3 (March 2007): 337–42. http://dx.doi.org/10.1016/j.ultsonch.2006.07.002.

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7

He, Zhen-Li, Anthony G. O'Donnell, Jinshui Wu, and J. Keith Syers. "Oxidation and transformation of elemental sulphur in soils." Journal of the Science of Food and Agriculture 65, no. 1 (May 1994): 59–65. http://dx.doi.org/10.1002/jsfa.2740650110.

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8

Wu, Zhi, Shui Ping Zhong, Zeng Ling Wu, Zhong Sheng Huang, and Brenda K. C. Chan. "Electrochemical Behavior of Carbon Paste Electrode with Gold-Bearing Pyrite in Bioleaching." Advanced Materials Research 825 (October 2013): 360–63. http://dx.doi.org/10.4028/www.scientific.net/amr.825.360.

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The dissolution of gold-bearing pyrite plays an important role in bioleaching of gold. This paper describes a fundamental study on the electrochemical behavior and reaction mechanisms of gold-bearing pyrite leaching in the form of Carbon Paste Electrode (CPE) with and without microorganisms using Cyclic Voltammetry (CV) and polarization curve. A two step process was suggested from Cyclic voltammetry. Electrode passivation by elemental sulphur was observed below 700mV (vs. SCE), elemental sulphur was then oxidized to sulphate when the electrode potential further increased from 700mV. The polarization current density of CPE and the oxidation rate of pyrite are further enhanced by the presence of microorganisms. Analyses of EDS and XPS confirmed the formation of elemental sulphur and sulphate. This electrochemical method successfully showed its simplicity and reliability to measure oxidation rate of gold bearing pyrite.

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9

Zhao, F. J., S. Y. Loke, A. R. Crosland, and S. P. McGrath. "Method to determine elemental sulphur in soils applied to measure sulphur oxidation." Soil Biology and Biochemistry 28, no. 8 (August 1996): 1083–87. http://dx.doi.org/10.1016/0038-0717(96)00073-9.

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10

Salamanca-Neto, Carlos Alberto Rossi, Jessica Scremin, Orlando Fatibello-Filho, Débora Nobile Clausen, and Elen Romão Sartori. "Assessment of the performance of triphenylphosphine for the voltammetric determination of elemental sulphur in cosmetic products." Analyst 143, no. 15 (2018): 3600–3606. http://dx.doi.org/10.1039/c8an00799c.

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11

Chapman, S. J. "Powdered elemental sulphur: oxidation rate, temperature dependence and modelling." Nutrient Cycling in Agroecosystems 47, no. 1 (February 1996): 19–28. http://dx.doi.org/10.1007/bf01985715.

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12

Urbanek, A., S. Razmadhan, and M. Jaworska. "Procedure for determination of elemental sulphur bio-oxidation rate." Bioprocess Engineering 4, no. 2 (1989): 91–94. http://dx.doi.org/10.1007/bf00373736.

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13

Belyi, A., Natalia Solopova, Vladimir Sekachev, Anatoliy Teleutov, Aleksandr Malashonok, and Grigoriy Krasilnikov. "Biooxidation of a Gold-Arsenic Sulphide Concentrate by a Two-Stage Oxidation Using Consecutively Acidophilic and Neutrophilic Bacteria." Advanced Materials Research 1130 (November 2015): 329–32. http://dx.doi.org/10.4028/www.scientific.net/amr.1130.329.

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This research work has developed a processing technology for full oxidation of the biocake from gold-arsenic flotation concentrate with high pyrrhotite content by neutrophilic association of microorganisms, which oxidize elemental sulphur and antimony sulphide at a high rate. Biocake, which is produced as a result of oxidizing the sulphides in the flotation concentrate at pH 1,7 – 1,9 by acidophilic bacteria of chemolithotrophic microorganisms and containing around 3%-5% of elemental sulphur, is then fully oxidized by association of neutrophilic bacteria at рН 7,0-8,0.

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14

Rabenstein, Andreas, Jörg Rethmeier, and Ulrich Fischer. "Sulphite as Intermediate Sulphur Compound in Anaerobic Sulphide Oxidation to Thiosulphate by Marine Cyanobacteria." Zeitschrift für Naturforschung C 50, no. 11-12 (December 1, 1995): 769–74. http://dx.doi.org/10.1515/znc-1995-11-1206.

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Abstract Anaerobic sulphide oxidation in the light was studied with seven cyanobacterial strains isolated from the southern Baltic Sea. All strains oxidized sulphide (1.2-3.5 mM) stoichio-metrically to thiosulphate. No elemental sulphur could be detected as end product of anoxy-genic photosynthesis. Sulphite as intermediate sulphur compound was released into the growth medium during anaerobic sulphide oxidation by these cyanobacteria. The formation of sulphite from sulphide was inhibited by the photosynthesis inhibitor DCMU. The cyanobacterium Oscillatoria sp. strain BO 32 produced another so far not identified intermediate sulphur compound which was probably stored within the cells.

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15

Brockley, R. P., and F. J. Sheran. "Foliar nutrient status and fascicle weight of lodgepole pine after nitrogen and sulphur fertilization in the interior of British Columbia." Canadian Journal of Forest Research 24, no. 4 (April 1, 1994): 792–803. http://dx.doi.org/10.1139/x94-104.

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The effects of nitrogen and nitrogen + sulphur fertilization on the first-year fascicle weight and foliar nutrient status of immature, thinned lodgepole pine (Pinuscontorta Dougl. var. latifolia Engelm.) were evaluated at seven locations in the interior of British Columbia. The results indicate that sulphur deficiencies, either aggravated or induced by nitrogen fertilization, may limit the responsiveness of lodgepole pine to nitrogen additions. At four locations, combined sulphur and nitrogen additions improved the sulphur status of fertilized trees and significantly increased the weight of fascicles produced during the first year after treatment compared with that achieved with nitrogen alone. Ammonium sulphate was a superior sulphur source compared with elemental sulphur–sodium bentonite prills and also was readily taken up by trees. The oxidation of the elemental sulphur prills was apparently too slow to satisfy sulphur requirements in the first year. Increasing the sulphur application rate from 50 to 100 kg/ha generally gave only small improvements in first-year fascicle weight response despite a significant improvement in foliar sulphur concentration and content. The responsiveness to sulphur fertilization was not consistent across all sites. Further characterization of sites that are responsive and unresponsive to sulphur additions is needed to more accurately diagnose sulphur deficiencies and predict responsiveness to sulphur additions.

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16

Wu, Lingbo, Baojun Yang, Xingxing Wang, Baiqiang Wu, Wanli He, Min Gan, Guanzhou Qiu, and Jun Wang. "Effects of Single and Mixed Energy Sources on Intracellular Nanoparticles Synthesized by Acidithiobacillus ferrooxidans." Minerals 9, no. 3 (March 8, 2019): 163. http://dx.doi.org/10.3390/min9030163.

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Effective biosynthesis of magnetite nanoparticles using current technology is challenging. We investigated the synthesis of nanoparticles by Acidithiobacillus ferrooxidans grown on ferrous iron, elemental sulphur, and mixtures of both substrates. A comparison of tests with different doping amounts of elemental sulphur in ferrous-containing medium showed that the addition of 0.25 and 0.5 M elemental sulphur to the medium resulted in an increased delay of microbial growth and ferrous iron oxidation. TEM suggested that the ferrous material was an essential energy source for the synthesis of nanoparticles in cells. TEM results indicated that the different ratios of ferrous and sulphur had no significant effect on the morphology of bacteria and the size of nanoparticles. High-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDX), and X-ray absorption near edge structure (XANES) showed that the nanoparticles were composed of magnetite. For the first time, HRTEM and XANES spectra in-situ characterization was conducted to investigate the nanoparticles that were synthesized by A. ferrooxidans. The findings from this study indicated that the different ratios of ferrous and sulphur had no significant effect on size and shape of nanoparticles synthesized by A. ferrooxidans.

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17

Yagnentkovsky, Nadia, M. Viera, and Edgardo R. Donati. "Recovery of Nickel and Zinc Using Biogenerated Sulphuric Acid." Advanced Materials Research 71-73 (May 2009): 649–52. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.649.

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Sludge generated in automotive and related industries often contains heavy metals. Bioleaching is an attractive alternative for the treatment of metal containing solids. Bacteria of the genus Acidithiobacillus are the most important microorganisms applied to metal solubilisation. These microorganisms are able to produce sulphuric acid from the aerobic oxidation of elemental sulphur. The biogenerated sulphuric acid can be applied to the solubilisation of metals from a solid matrix. In this paper we present the results of our experiments aimed at the removal of nickel and zinc from sludge generated in the water treatment plant of an automotive industry. Acidithiobacillus thiooxidans cells were immobilised on sulphur pearls in a column reactor. The effects of sulphur pulp density and the dilution rate on the production of sulphuric acid were studied. In a second stage, sulphuric acid was used to solubilise the nickel and zinc from the sludge. The effects of different sludge pulp densities and initial acid pH were studied. High recoveries of zinc and nickel were obtained when the pH value of the sulphuric acid solution was lower than 2.0 for 1 and 2 % of pulp density.

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18

Grant, C. A., A. M. Johnston, and G. W. Clayton. "Sulphur fertilizer and tillage management of canola and wheat in western Canada." Canadian Journal of Plant Science 84, no. 2 (April 1, 2004): 453–62. http://dx.doi.org/10.4141/p02-083.

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A 3-yr field study in Manitoba, Saskatchewan and Alberta evaluated immediate and residual effects of source, timing and placement of sulphur fertilizers on canola (Brassica napus L.) and wheat (Triticum aestivumL.) under conventional (CT) and reduced tillage (RT). Sulphur fertilization did not increase wheat yield, even when soil sulphate was low. Ammonium sulphate (AS) and ammonium thiosulphate (ATS) increased canola yield in 2 of 3 yr at the Saskatchewan site while elemental S and Tiger 90™ did not. Residual S from AS and ATS increased canola yield on S-deficient soils in the second and third crops after application. Canola yield on the S-deficient soil was lower where broadcast Tiger 90 rather than AS or ATS was applied the previous year, indicating that broadcast Tiger 90 oxidation was insufficient to support canola yield in the second crop year after application. Banding or seed-placing Tiger 90 delayed oxidation further. In the third crop after application, canola yield was similar with broadcast Tiger 90, AS or ATS but was lower with seed-placed or banded Tiger 90 than AS or broadcast Tiger 90. Small particle size and broadcast application of elemental S are needed to hasten oxidation of S to sulphate-S. Key words: Elemental S, Bentonite S, zero tillage, reduced tillage

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19

Matsui, Saburo, and Ryoko Yamamoto. "A New Method of Sulphur Denitrification for Sewage Treatment by a Fluidized Bed Reactor." Water Science and Technology 18, no. 7-8 (July 1, 1986): 355–62. http://dx.doi.org/10.2166/wst.1986.0308.

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Anaerobic treatment of sewage has a problem of denitrification, because that organic carbon and hydrogen are recoverd mainly in the form of methane and not used for denitrification. Other electron donors must be introduced. Promising donors are reduced forms of sulphur. In this study, thiosulphate and elemental sulphur were used in fluidized bed reactor systems. Denitrification by oxidation of sulphur was unstable due to poor solubility of sulphur into sewage. Thiosulphate denitrification was very stable. Stoichiometric relationship of the denitrification and thiosulphate oxidation for the reactor was obtained. The denitrification process was described by the first order consecutive reactions. The rate constant of nitrate to nitrite reduction, kl varied between 2.05×10−2 and 1.09×10−1 (1/gVSS/l*min.). The rate constant of nitrite to nitrogen reduction, k2 varied between 1.41×10−1 and 9.08×10−1 (l/gVSS/l*min.).

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20

Candy, Rachel M., Kyle R. Blight, and David E. Ralph. "Analysis of the Bacterial Sulphur System." Advanced Materials Research 825 (October 2013): 190–93. http://dx.doi.org/10.4028/www.scientific.net/amr.825.190.

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Heterogeneous bacterial sulphur systems are inherently complicated. However, developing an understanding of the influence of environmental factors such as pH,Iand PCO2is important for a number of fields. Examples of these include minimising acid mine drainage and maximising metal recovery from low-grade sulphide minerals. Measuring the effect of these factors on the extent and rate of sulphur (S) oxidation is complicated by the presence and nature of solid phase elemental S. The rate and extent of S oxidation can be determined indirectly via the reaction product, H2SO4, which was quantified using pH measurements in this study. The method was critically dependent on the quality of pH data but proved effective in providing rate constants for the catalysed S oxidation reaction and yield (biomass/substrate) estimates in the range pH > 1.5. IncreasingIover the range 0.176 0.367 mol L-1decreased bacterial cell yields but increased the rate of sulphur oxidation significantly. Partial pressures of CO2in the range of 0.039 1.18% v/v produced no significant effect on the rates of S oxidation or bacterial cell yields. Bacterial cell yields were not affected in the pH range 1.5 2.5, however the rate of S oxidation increased significantly from pH 2.0 2.5. In the range pH < 1.5 the batch cultures progressed and although no reliable rate data was recorded cell yields decreased from 7.43 to 2.05 (× 1012cells mol-1) at pH 1.5 to 1.0 respectively.

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21

Grant, C. A., A. M. Johnston, and G. W. Clayton. "Sulphur fertilizer and tillage effects on early season sulphur availability and N:S ratio in canola in western Canada." Canadian Journal of Soil Science 83, no. 4 (August 1, 2003): 451–63. http://dx.doi.org/10.4141/s02-046.

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Field studies in Manitoba, Saskatchewan and Alberta over 3 yr evaluated immediate and residual effects of source, timing and placement of S fertilizers on sulphate-S supply to canola (Brassica napus L.). The treatments were compared under conventional tillage (CT) and in the establishment years of a reduced (RT) system. Sulphate-S in the soil was measured for two weeks after seeding, using PRSTM-probes. Sulphur concentration and N:S ratio were measured in canola tissue at flowering. Tillage system had little effect on available sulphate, tissue S concentration, N:S ratio or response to S fertilization. Ammonium sulphate (AS) generally increased tissue S concentration and reduced N:S ratio with all placements, and the effects of surface-applied ammonium thiosulphate (ATS) were similar to the effects of AS. Tiger 90, a bentonite-elemental S formulation, generally produced lower S concentrations in canola tissue at flowering than did AS, and levels were similar with elemental S and Tiger 90. Both tissue S concentration and N:S ratio were good indicators of S sufficiency for canola. Sulphate carryover from AS increased tissue S concentration and decreased N:S ratio in the year following application. In contrast, increases in tissue S concentration and decreases in N:S ratio were lower with Tiger 90 than AS. The oxidation of the residual elemental S in Tiger 90 could not be relied upon to increase tissue S concentration above deficiency levels in the year following application where soil sulphate levels were low. Key words: Elemental S, bentonite S, zero tillage, N:S ratio, PRS-probes

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22

Pietrzak, Robert, Helena Wachowska, and Piotr Nowicki. "The effect of flame coal oxidation on the solid and soluble products of its extraction." Open Chemistry 3, no. 4 (December 1, 2005): 852–65. http://dx.doi.org/10.2478/bf02475208.

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AbstractSolid and soluble products of THF and CH2Cl2 extraction of flame coal oxidised by four different oxidising agents (peroxyacetic acid (PAA), 5% HNO3, O2/Na2CO3, air/125 °C) were studied by elemental analysis and FTIR. The extraction yield with THF was much higher than that with CH2Cl2 for all samples. The greatest changes in elemental composition were in the extracts from coal oxidised by nitric acid. The sulphur content was lowest in extracts from coal oxidised with 5% HNO3 and PAA. FTIR confirmed that coal treatment with nitric acid incorporates nitrogen into the coal structure.

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23

KAMETANI, Hiroshi, Mikihiko KOBAYASHI, and Kei YAMADA. "Electrochemical Aspects of Aqueous Oxidation of Elemental Sulphur Activated by Cupric Sulphide." Journal of the Mining Institute of Japan 101, no. 1173 (1985): 725–31. http://dx.doi.org/10.2473/shigentosozai1953.101.1173_725.

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24

Zhao, Cuicui, Vadakattu V. S. R. Gupta, Fien Degryse, and Mike J. McLaughlin. "Effects of pH and ionic strength on elemental sulphur oxidation in soil." Biology and Fertility of Soils 53, no. 2 (January 5, 2017): 247–56. http://dx.doi.org/10.1007/s00374-016-1170-0.

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25

Beffa, Trello. "Inhibitory action of elemental sulphur (S°) on fungal spores." Canadian Journal of Microbiology 39, no. 8 (August 1, 1993): 731–35. http://dx.doi.org/10.1139/m93-107.

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The fungitoxic effect of increasing concentrations of elemental sulphur (S°) was studied during the pregermination period of spores of Phomopsis viticola and conidia of Neurospora crassa. High concentrations of S° (> 10 μM final concentration) inhibited respiratory activities strongly and decreased the ATP content of spores and conidia. S° at low concentrations (1 and 3 μM final concentration) did not inhibit the respiratory activities or ATP content of spores and conidia. In spores of P. viticola, low concentrations of S° were reduced by the cells with the production of hydrogen sulphide (H2S), principally at the level of the respiratory chain. However, in the presence of a high concentration of S°, the capacity to reduce S° increased, and was then most probably independent of the respiratory activities. Proteic and nonproteic sulphydryl groups important in cellular metabolism were probably responsible for almost all the reduction of S°. In fact, the addition of increasing concentrations of S° to spores of P. viticola resulted in a dramatic increase in oxidized glutathione, suggesting the participation of reduced glutathione in S° reduction. In conclusion, we suggest that the fungicidal action of S° is probably related to the oxidation of important sulphydryl groups and not to the competitive interaction between S° and oxygen at the level of the respiratory chain.Key words: elemental sulphur, fungicide, fungi, Neurospora crassa, Phomospis viticola.

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26

Ndlovu, Sehliselo, Geoffrey S. Simate, and Mariekie Gericke. "The Microbial Assisted Leaching of Nickel Laterites Using a Mixed Culture of Chemolithotrophic Microorganisms." Advanced Materials Research 71-73 (May 2009): 493–96. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.493.

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Nickel laterite contains metal values but is not capable of participating in the primary chemolithotrophic bacterial oxidation because it contains neither Fe2+ iron nor substantial amount of reduced sulphur. Its metal value can, however, be recovered by allowing the primary oxidation of FeS2, or similar iron/sulphur minerals to provide H2SO4 acid solutions, which solubilise the metal content. This study investigated the possibility of treating nickel laterites using chemolithotrophic microorganisms. Preliminary studies conducted using H2SO4 acid, citric acid and acidified Fe2(SO4)3 gave an insight on the use of chemolithotrophic bacteria in this process,. Results showed that H2SO4 acid performed better, in terms of nickel recovery, than citric acid or acidified Fe2(SO4)3. In the bacterial leaching test works, mixed cultures of Acidithiobacillus ferrooxidans, Acidithiobacillus caldus and Leptospirillum ferrooxidans were used in the presence of elemental sulphur and FeS2 as energy sources. The sulphur substrate exhibited better effects in terms of bacterial growth, acidification and nickel recovery than the FeS2 substrate. Using response surface methodology, the theoretical optimum conditions for maximum nickel recovery (79.8%) within the conditions studied was an initial pH of 2.0, 63μm particle size and 2.6% pulp density.

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27

Khoshkhoo, Mohammad, Mark Dopson, and Åke Sandström. "Role of Microbial Activity in Bioleaching of a Pyritic and a Pure Chalcopyrite Concentrate." Advanced Materials Research 1130 (November 2015): 209–13. http://dx.doi.org/10.4028/www.scientific.net/amr.1130.209.

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Leaching of a pyritic and a pure chalcopyrite concentrate was carried out in stirred tank reactors in the absence and presence of a mixed culture of moderately thermophilic microorganisms at 45°C and pH 1.5. To study the effect of microbial activity on copper dissolution, the abiotic experiments were performed under accurately controlled redox potential conditions to reproduce the same oxidising conditions recorded during the bioleaching experiments. X-ray photoelectron spectrometry (XPS) was used to study the surface of chalcopyrite chips leached for different durations. The results showed that the microorganisms in cases of both concentrates did not have any effect in the copper leaching efficiency other than oxidation of ferrous to ferric ions. Biooxidation of elemental sulphur did not improve the leaching efficiency and bulk and surface jarosite had no negative effect on dissolution. A composite layer composed of mainly elemental sulphur and iron-oxy-hydroxide was found to be responsible for the hindered dissolution.

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28

Mondragón, Fanor, Wilson Ruı́z, and Alexander Santamarı́a. "Effect of early stages of coal oxidation on its reaction with elemental sulphur." Fuel 81, no. 3 (February 2002): 381–88. http://dx.doi.org/10.1016/s0016-2361(01)00143-0.

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29

de Sousa, José Tavares, Jéssyca de Freitas Lima, Valquíria Cordeiro da Silva, Valderi Duarte Leite, and Wilton Silva Lopes. "Recovery of elemental sulphur from anaerobic effluents through the biological oxidation of sulphides." Environmental Technology 38, no. 5 (June 30, 2016): 529–37. http://dx.doi.org/10.1080/09593330.2016.1201148.

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30

Jolivet, Pascale, Edith Bergeron, Alain Zimierski, and Jean-Claude Meunier. "Metabolism of elemental sulphur and oxidation of sulphite by wheat and spinach chloroplasts." Phytochemistry 38, no. 1 (January 1995): 9–14. http://dx.doi.org/10.1016/0031-9422(94)00651-9.

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31

Jaworska, M., and A. Urbanek. "The influence of oxygen concentration in liquid medium on elemental sulphur oxidation by." Bioprocess Engineering 18, no. 3 (1998): 201. http://dx.doi.org/10.1007/s004490050431.

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32

Neilsen, D., E. J. Hogue, P. B. Hoyt, and B. G. Drought. "Oxidation of elemental sulphur and acidulation of calcareous orchard soils in southern British Columbia." Canadian Journal of Soil Science 73, no. 1 (February 1, 1993): 103–14. http://dx.doi.org/10.4141/cjss93-010.

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The capacity of soils to oxidize S was measured by incubation with finely divided elemental S in 13 calcareous orchard soils from the southern interior of British Columbia. Sulphur oxidation rates ranged from 3.4 to 26 μg S cm−2 d−1. The magnitude of pH decrease in response to added S varied inversely with initial CaCO3 content (r = − 0.58, P = 0.04) and silt content (r = − 0.64, P = 0.02) and directly with sand content (r = 0.64, P = 0.02). Incubation studies with one calcareous orchard soil indicated that finely divided S was more effective over time than other acidulants (FeSO4, Al2 (SO4)3 and H2SO4). A field study was carried out on the same soil. Finely divided and bentonitic granulated S were applied at 4.5 t ha−1 on the grass surface or incorporated to a depth of 15 cm. Incorporated fine S was oxidized to a much greater extent during a 2-yr period than was incorporated grandulated S. However, when surface applied, they were oxidized equally but slowly. Key words: S incubation, acidulating materials, S oxidation, soil pH, electrical conductivity

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33

Vannini, Claudia, Giulio Munz, Gualtiero Mori, Claudio Lubello, Franco Verni, and Giulio Petroni. "Sulphide oxidation to elemental sulphur in a membrane bioreactor: Performance and characterization of the selected microbial sulphur-oxidizing community." Systematic and Applied Microbiology 31, no. 6-8 (December 2008): 461–73. http://dx.doi.org/10.1016/j.syapm.2008.07.003.

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34

Nwachukwu, Ifeanyi D., Alan J. Slusarenko, and Martin C. H. Gruhlke. "Sulfur and Sulfur Compounds in Plant Defence." Natural Product Communications 7, no. 3 (March 2012): 1934578X1200700. http://dx.doi.org/10.1177/1934578x1200700323.

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The multiplicity of chemical structures of sulfur containing compounds, influenced in part by the element's several oxidation states, directly results in diverse modes of action for sulfur-containing natural products synthesized as secondary metabolites in plants. Sulfur-containing natural products constitute a formidable wall of defence against a wide range of pathogens and pests. Steady progress in the development of new technologies have advanced research in this area, helping to uncover the role of such important plant defence molecules like endogenously-released elemental sulphur, but also deepening current understanding of other better-studied compounds like the glucosinolates. As studies continue in this area, it is becoming increasingly evident that sulfur and sulfur compounds play far more important roles in plant defence than perhaps previously suspected.

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35

Jolivet, Pascale, Edith Bergeron, and Jean-Claude Meunier. "Oxidation of 35S-labelled elemental sulphur by wheat chloroplasts and analysis of 35s-products." Phytochemistry 34, no. 6 (December 1993): 1467–71. http://dx.doi.org/10.1016/s0031-9422(00)90829-x.

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36

Cowan, Denver H., Fazel G. Jahromi, and Ahmad Ghahreman. "Atmospheric oxidation of pyrite with a novel catalyst and ultra-high elemental sulphur yield." Hydrometallurgy 173 (November 2017): 156–69. http://dx.doi.org/10.1016/j.hydromet.2017.07.003.

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37

Jaworska, M., and A. Urbanek. "The influence of carbon dioxide concentration in liquid medium on elemental sulphur oxidation by." Bioprocess Engineering 16, no. 6 (1997): 361. http://dx.doi.org/10.1007/s004490050336.

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38

Bonstrom, Kristie, S. Lee Barbour, and M. Jim Hendry. "Physical and hydraulic characterization of fractured, hydrophobic sulphur within above-ground sulphur blocks." Canadian Geotechnical Journal 46, no. 12 (December 2009): 1461–72. http://dx.doi.org/10.1139/t09-066.

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Volatility in the price of sulphur has resulted in the temporary storage of sulphur in large, surface blocks at oil sands properties in northern Alberta, Canada, that are subject to oxidation which produces acidic effluent. Characterization of water storage and migration within these blocks is required to assess potential environmental impacts. Investigation of the elemental sulphur (S0) blocks at Syncrude’s Mildred Lake site included fracture mapping and laboratory testing of core samples for density and permeability to air and water. Internal porosity was mapped with X-ray tomography, and water-intrusion porosimetry was used to define saturation–pressure relationships. The blocks have regular polygonal fractures with a porosity of approximately 1.4%. The mean total and water-available porosity of core samples was 9% and 6%, respectively. The water-entry pressure head was 1–2 m for matrix pores, but only 1–2 mm for fractures. Estimated functional relationships for volumetric water content versus water pressure of the fracture and matrix system are used to illustrate how infiltration is likely to occur rapidly along fracture pathways but with insufficient pressure to allow water to penetrate the matrix, suggesting that acid production occurs by flushing of the fracture surface with little influence from the matrix.

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39

Lee, Albert, J. H. Watkinson, and D. R. Lauren. "Factors affecting oxidation rates of elemental sulphur in a soil under a ryegrass dominant sward." Soil Biology and Biochemistry 20, no. 6 (January 1988): 809–16. http://dx.doi.org/10.1016/0038-0717(88)90086-7.

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40

Jaworska, M., and A. Urbanek. "The influence of oxygen concentration in liquid medium on elemental sulphur oxidation by Thiobacillus thiooxidans." Bioprocess Engineering 18, no. 3 (March 23, 1998): 201–5. http://dx.doi.org/10.1007/pl00008983.

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41

Yemelyanova, V. S., H. Kurokawa, B. T. Dossumova, Zh K. Kairbekov, T. V. Shakiyeva, Zh K. Myltykbaeva, U. N. Dzhatkambayeva, E. M. Shakiyev, and E. Zh Aybasov. "Using of Microspheres of Power Ashes for Gases Cleaning from Sulphur Dioxide." Advanced Materials Research 1079-1080 (December 2014): 110–17. http://dx.doi.org/10.4028/www.scientific.net/amr.1079-1080.110.

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The composition and structure of the microspheric aluminosilicates of Combined Heating and Power Plants (CHРP) ashes is studied with the help of modern physical-chemical methods (XRD, scanning electron microscopy, BET, elemental and chemical analysis). The activity of microsphere-based catalysts for the reaction of Na2SO3 oxidation by oxygen is also studied by kinetic and potentiometric methods. By means of EPR and Möessbauer spectroscopy it is concluded that iron ions into the composition of cenospheres exist in two states – Fe3+ and Fe2+, thus, the iron (III) is in the form of solitary ions in an aluminosilicate matrix in the range of the iron content 3-4 mass %.

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42

Mulopo, Jean, and L. Schaefer. "Biological regeneration of ferric (Fe3+) solution during desulphurisation of gaseous streams: effect of nutrients and support material." Water Science and Technology 71, no. 11 (March 30, 2015): 1672–78. http://dx.doi.org/10.2166/wst.2015.144.

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This paper evaluates the biological regeneration of ferric Fe3+ solution during desulphurisation of gaseous streams. Hydrogen sulphide (H2S) is absorbed into aqueous ferric sulphate solution and oxidised to elemental sulphur, while ferric ions Fe3+ are reduced to ferrous ions Fe2+. During the industrial regeneration of Fe3+, nutrients and trace minerals usually provided in a laboratory setup are not present and this depletion of nutrients may have a negative impact on the bacteria responsible for ferrous iron oxidation and may probably affect the oxidation rate. In this study, the effect of nutrients and trace minerals on ferrous iron oxidation have been investigated and the results showed that the presence of nutrients and trace minerals affects the efficiency of bacterial Fe2+oxidation. The scanning electron microscopy analysis of the geotextile support material was also conducted and the results showed that the iron precipitate deposits appear to play a direct role on the bacterial biofilm formation.

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43

Bai, Jing, Jiang Kang Wen, Song Tao Huang, Biao Wu, and Shuang Liu. "The Leaching Behaviours of Chalcopyrite with Distinct Genetic Types." Advanced Materials Research 1033-1034 (October 2014): 1288–91. http://dx.doi.org/10.4028/www.scientific.net/amr.1033-1034.1288.

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The copper extraction yield from chemical leaching of chalcopyrite depends on temperature, pH, and the oxidation-reduction potential (ORP), as well as on the different genetic type of the chalcopyrite used. The chemical leaching characteristics of chalcopyrite from marine volcanic type and porphyry type were studied. It was found that the intermediates of marine volcanic chalcopyrite and porphyry chalcopyrite elucidated from the MLA were elemental sulphur and non-stoichiometric minerals, such as Cu3.5Fe4S2.5, Cu5Fe4S and Cu3.5Fe1.5S5. The results suggested that the main difference between marine volcanic chalcopyrite and porphyry chalcopyrite is the rates of copper and iron ions dissolution from chalcopyrite crystal lattice.

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44

Verver, A. B., and W. P. M. Van Swaaij. "The rate of oxidation of hydrogen sulphide by oxygen to elemental sulphur over NaX and NaY zeolites and the adsorption of sulphur." Applied Catalysis 14 (January 1985): 185–202. http://dx.doi.org/10.1016/s0166-9834(00)84354-7.

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45

Lee, A., J. H. Watkinson, G. Orbell, J. Bagyaraj, and D. R. Lauren. "Factors influencing dissolution of phosphate rock and oxidation of elemental sulphur in some New Zealand soils." New Zealand Journal of Agricultural Research 30, no. 3 (July 1987): 373–85. http://dx.doi.org/10.1080/00288233.1987.10421898.

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46

Jaworska, M., and A. Urbanek. "The influence of carbon dioxide concentration in liquid medium on elemental sulphur oxidation by Thiobacillus thiooxidans." Bioprocess Engineering 16, no. 6 (May 22, 1997): 361–65. http://dx.doi.org/10.1007/pl00008949.

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47

ANDERSON, A. E., J. J. CHILDRESS, and J. A. FAVUZZI. "Net uptake of CO2 Driven by Sulphide and Thiosulphate Oxidation in the Bacterial Symbiont-Containing Clam Solemya Reidi." Journal of Experimental Biology 133, no. 1 (November 1, 1987): 1–31. http://dx.doi.org/10.1242/jeb.133.1.1.

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Solemva reidi Bernard is a gutless clam that lives in burrows in reducing sediments, and harbours intracellular sulphur-oxidizing bacteria in its gills. Clams were incubated in various concentrations of sulphide and thiosulphate for up to 65 h in a flow-through respirometer. Fluxes were determined by continuous sampling of the respiratory medium with analysis of CO2, O2 and sulphide by gas chromatography and analysis of thiosulphate, sulphite (and sulphide) by HPLC using monobromobimane-denvatized discrete samples. Net CO2 uptake was shown to occur with exposure to 50–100μmol1−1 sulphide and greater than 225μmoll−1 thiosulphate; sulphide oxidation and thiosulphate uptake were also demonstrated. 45CaCO3 deposition in the shells of. S. reidi was found to be insignificant compared to the net CO2 flux measured in the presence of low levels of sulphide. In experiments conducted under various O2 conditions, O2 limitation, produced by a combination of low [O2] and low water flow, was shown to inhibit sulphide oxidation and to prevent Co2 uptake. However, if O2 supply was not limited by low flow rates, in the presence of low [O2] (25–40 μmoll−1) S. reidi showed rates of O2 and sulphide consumption and CO2 uptake near the maximum levels determined under high [O2] conditions, indicating the potential for net Co2 uptake in the low [O2] conditions presumed to exist in the animal's burrows. Thiosulphate levels in the blood of S. reidi were analysed and shown to increase rapidly during incubation in sulphide. These levels reached an apparent steady state (approx. 300μmoll−1) in recently captured clams after 1 h of incubation. However, both O2 limitation and time in captivity (>43 days after capture) caused a marked increase in the blood thiosulphate levels, which exceeded 2.5mmoll−1 after 16 h of exposure to sulphide. These results indicate that blood thiosulphate is transported to the bacteria and further oxidized, and that sulphide and thiosulphate oxidation are oxygen-dependent. In analyses of gill tissues for elemental sulphur, we found a wide range in the levels of sulphur stores. Calculations indicated these to be a small fraction of the total flux of sulphur maintained during continuous sulphide oxidation. Estimates of Co2:o2: sulphide ratios suggest CO2 fixation efficiencies similar to those of chemolithoautotrophic bacteria. Assuming translocation and oxidation of symbiont-fixed organic compounds, the net uptake of CO2 by S. reidi in the presence of reduced sulphur compounds suggests that this intact symbiosis may be able to meet its organic carbon needs through autotrophy.

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48

Abraitis, P. K., R. A. D. Pattrick, G. H. Kelsall, and D. J. Vaughan. "Acid leaching and dissolution of major sulphide ore minerals: processes and galvanic effects in complex systems." Mineralogical Magazine 68, no. 2 (April 2004): 343–51. http://dx.doi.org/10.1180/0026461046820191.

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AbstractThe kinetics and mechanisms of dissolution of the major base metal sulphide minerals, pyrite, chalcopyrite, galena and sphalerite in acidic (chloride) media have been investigated. Minerals were ground in air, then dissolved in air-equilibrated solutions at pH 2.5, while monitoring the redox potential. Solution samples were analysed by ICP-AES and HPLC, and surfaces of residual sulphides analysed using XPS. Dissolution of aerial oxidation products on pyrite particles in the first 15 min apparently led to a sulphur-rich surface, and was followed by slower dissolution of pyrite itself, driven by oxygen reduction, and resulting in net production of protons. Chalcopyrite dissolution resulted in a Cu, S-rich (near) surface layer, accompanied by net consumption of protons. Apparently incongruent dissolution of galena and sphalerite may reflect the formation of elemental S at the surface. The rates of dissolution of chalcopyrite, galena and sphalerite in the presence of pyrite were determined, respectively, as 18, 31 and 1.5 times more rapid than in single-mineral experiments. These data were consistent with galvanically-promoted mineral oxidation of the other sulphides in the presence of pyrite. In the case of galena, the experimental data suggested extensive release of Pb ions and development of a sulphur-rich surface during galvanically-promoted dissolution.

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49

Nolasco, Costanza, Patricia A. Chiacchiarini, Teresa Laura Lavalle, and Alejandra Giaveno. "A Novel Acidianus Strain Isolated from Copahue, Argentina Involved in the Sulphur Cycle of a Volcanic Environment." Advanced Materials Research 825 (October 2013): 66–69. http://dx.doi.org/10.4028/www.scientific.net/amr.825.66.

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The extremely thermophilic archaea have become a research hotspot in the recent years because of their extreme living conditions, physicochemical characteristics such as the oxidation of sulphur, metal sulphide ore and excellent leaching capability of metal sulphides. A novel thermoacidophilic archaea (ALE1 strain) of the genusAcidianus,CandidatusAcidianus copahuensis, was isolated from the Copahue Volcano area, in Neuquén, Argentina. This strain was able to metabolize different sulphur compounds under aerobic and anaerobic conditions. ALE1 strain was inoculated in M88, a selective medium for thermoacidophilic archaea recommended by DSMZ. Elemental sulphur (So) and potassium tetrathionate (T) were used alternatively as the energy source, while oxygen and iron (III) were the electron acceptors in the aerobic and anaerobic tests respectively. All systems were incubated at 70oC in shake flasks. The pH, Eh, [H+] and cell concentration were measured. The results from the aerobic test confirm that ALE1 strain was able to oxidize (So) and (T) decreasing the pH significantly, reaching the values 1 and 1.5, respectively. A light yellow precipitate was formed only in the inoculated systems in presence of (T). It was characterized by SEM and FTIR techniques showing that only sulphur atoms are bonded together in some way not confirmed yet. In the anaerobic tests, it was found that ALE1 was able to oxidize sulphur and tetrathionate ion transferring electrons to iron (III) acceptor. The Eh decreased in all inoculated systems from nearly 500mV to 300mV approximately. This work shows that ALE1 strain is helping to keep active the sulphur cycle in the Copahue volcanic environment; however the challenge is to elucidate the metabolism involved.

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50

Frías, C., F. Sánchez, D. Martín, G. Díaz, and S. Sanguilinda. "Indirect Bioleaching and ZINCEX^TM Process: A Profitable Marriage to Process Zinc Polymetallic Concentrates." Advanced Materials Research 71-73 (May 2009): 429–32. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.429.

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Indirect bioleaching is a biotechnology that presents important advantages when apply to bioprocessing of zinc and zinc polymetallic concentrates such as high metals recovery, fast kinetic of 4-5 hours to get full metals extraction, sulphur oxidation to elemental sulphur (avoiding sulphuric acid generation, while pyrite mineral remains untouched), and use of conventional reactors (aeration is not required) and normal process equipments. On the other hand, the development of high-efficiency bioreactors for ferrous iron bio-oxidation based on flooded fixed-bed model has opened the way to succeed in the potential commercial application of this innovative bio-hydrometallurgical technology, being especially attractive to benefit zinc and lead bulk or polymetallic concentrates containing other valuable metals like silver. In addition, a great variety of concentrates is feasible to be processed, e.g. in the range of 15% to 60% Zn and Pb metals content. That aim, within European Biomine project, for the first time in biohydrometallurgy field, indirect bioleaching technology applied on Zn/Pb polymetallic concentrates has been demonstrated in continuous in an integrated pilot plant at Tecnicas Reunidas’ (TR) R&D Centre in Madrid (Spain) producing electrolytic SHG zinc plates. Overall zinc recovery in the integrated pilot facility after more than 300 operating hours has been above 95% thanks to the ability and good performance of the ZincexTM technology (solvent extraction and electrowinning), in which obtaining of SHG electrolytic zinc is fully guaranteed with high current efficiency (above 93%) and good deposit morphology. In definitive, a profitable marriage between indirect bioleaching process and ZincexTM technology has been successfully demonstrated in TR facilities at pilot plant scale, and main results of such integrated pilot plant operation are presented in this paper.

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