Journal articles: 'Metal sulfide'

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Zhang, Ya Hui, Xi Cheng, and Qing Wang. "A Low Temperature Precursor Sulfuration Route to Metal Sulfides Nanomaterials." Advanced Materials Research 148-149 (October 2010): 1404–7. http://dx.doi.org/10.4028/www.scientific.net/amr.148-149.1404.

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A low-temperature precursor sulfuration route has been established to prepare metal sulfides with different nanostructures during the synthesis of nickel sulfide. The advantages of the low-temperature precursor sulfuration route were testified by the synthesis of different metal sulfides ( lead sulfide, zinc sulfide and cobalt sulfide). It offers a novel path to the preparation of other metal sulfides.

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Jayaranjan, Madawala Liyanage Duminda, and Ajit P. Annachhatre. "Precipitation of heavy metals from coal ash leachate using biogenic hydrogen sulfide generated from FGD gypsum." Water Science and Technology 67, no. 2 (January 1, 2013): 311–18. http://dx.doi.org/10.2166/wst.2012.546.

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Investigations were undertaken to utilize flue gas desulfurization (FGD) gypsum for the treatment of leachate from the coal ash (CA) dump sites. Bench-scale investigations consisted of three main steps namely hydrogen sulfide (H2S) production by sulfate reducing bacteria (SRB) using sulfate from solubilized FGD gypsum as the electron acceptor, followed by leaching of heavy metals (HMs) from coal bottom ash (CBA) and subsequent precipitation of HMs using biologically produced sulfide. Leaching tests of CBA carried out at acidic pH revealed the existence of several HMs such as Cd, Cr, Hg, Pb, Mn, Cu, Ni and Zn. Molasses was used as the electron donor for the biological sulfate reduction (BSR) process which produced sulfide rich effluent with concentration up to 150 mg/L. Sulfide rich effluent from the sulfate reduction process was used to precipitate HMs as metal sulfides from CBA leachate. HM removal in the range from 40 to 100% was obtained through sulfide precipitation.

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Anenburg, Michael, and John A. Mavrogenes. "Noble metal nanonugget insolubility in geological sulfide liquids." Geology 48, no. 9 (June 5, 2020): 939–43. http://dx.doi.org/10.1130/g47579.1.

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Abstract Noble metals (NMs) in Earth’s magmatic systems are thought to be controlled entirely by their strong partitioning to sulfide liquids. This chemical equilibrium is at the root of various models, ranging from NM deposit formation to planetary differentiation. Noble metals commonly occur as sub-micrometer phases known as nanonuggets. However, the assumptions that nanometer-scale thermodynamic equilibrium partitioning is attained and that NM nanonuggets are soluble in sulfide liquids have never been validated. Using novel experimental methods and analytical techniques we show nanometer-scale NM ± Bi phases attached to exterior surfaces of sulfide liquids. Larger phases (≤1 µm) show clear liquid immiscibility textures, in which Fe, Cu, and Ni partition into sulfide liquids whereas NMs partition into bismuthide liquids. Noble metal compositions of sulfides and their associated NM phases vary between adjacent droplets, indicating NM disequilibrium in the system as a whole. We interpret most nanometer-scale NMs contained within sulfides to be insoluble as well, suggesting that previously reported sulfide–silicate partition coefficients are overestimated. Consequently, sulfide liquids likely play a secondary role in the formation of some NM ore deposits.

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Huergo, J., C. Bernardelli, M. Viera, Wolfgang Sand, and Edgardo R. Donati. "FISH Analysis of Bacterial Attachment to Copper Sulfides in Bioleaching Processes." Advanced Materials Research 71-73 (May 2009): 329–32. http://dx.doi.org/10.4028/www.scientific.net/amr.71-73.329.

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Bioleaching is the biological conversion of an insoluble metal compound into a water soluble form. In this process metal sulfides are oxidized to metal ions and sulfate by acidophilic microorganisms capable of oxidizing Fe2+ and/or sulfur-compounds. The metal solubilization from sulfide minerals is a chemical process which requires Fe3+ reduction. It is an environmentally friendly technique and an economical method for recovering metals that requires low investment and operation costs. In this work we studied the bioleaching of two kinds of acid-soluble copper sulfides, one easily leached by mesophilic bacteria (covellite), and the other one refractory to their activity (chalcopyrite), in acidic media with or without Fe2+ ions. We studied attached and planktonic populations of autotrophic bacteria, such as Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans in pure or mixed cultures. The influence of a heterotrophic microorganism, Acidiphilium cryptum, was also studied. Attachment was evaluated with fluorescence staining and FISH using four specific probes. L. ferrooxidans showed highest initial attachment in all cases. The presence of Ap. cryptum increased the cell attachment compared with the autotrophic pure cultures. It was possible to correlate experimental data with a mechanism of bacterial-metal sulfide oxidation, the polysulfide pathway for acid- soluble metal sulfides.

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Moroz, O. M., S. O. Hnatush, O. V. Tarabas, C. I. Bohoslavets, G. V. Yavorska, and B. M. Borsukevych. "Sulfidogenic activity of sulfate and sulfur reducing bacteria under the influence of metal compounds." Biosystems Diversity 26, no. 1 (April 5, 2018): 3–10. http://dx.doi.org/10.15421/011801.

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Due to their high content in natural environments, heavy metals exhibit toxic effects on living organisms, which leads to a decrease in the biological diversity and productivity of ecosystems. In niches with low oxidation reducing potential, sulfate and sulfur reducing bacteria carry out the reducing transformation of oxidized sulfur compounds with the formation of significant amounts of hydrogen sulfide. H2S produced by bacteria interacts with metal ions, precipitating them in the form of sulfides. The aim of this work was to investigate the influence of lead, cuprum (II), iron (II) and manganese (II) salts on the production of hydrogen sulfide by bacteria of the Desulfovibrio and Desulfuromonas genera, isolated from Yavorivske Lake, and to evaluate the efficiency of their use for purifying media, enriched with organic compounds, from hydrogen sulfide and heavy metals. The content of heavy metal ions in the water of Yavorivske Lake was determined by the spectrophotometric method. The bacteria were grown for 10 days at 30 °C in the Kravtsov-Sorokin medium under anaerobic conditions. To study the influence of metal ions on bacteria growth and their H2S production, cells were incubated with metal salts (0.5–4.0 mM), washed and grown in media with SO42– or S0. To determine the level of metal ions binding by H2S, produced by bacteria, cells were grown in media with metal compounds (0.5–4.0 mM), SO42– or S0. Biomass was determined by turbidimetric method. In the cultural liquid the content of H2S was determined quantitatively by spectrophotometric method, and qualitatively by the presence of metal cations. The content of metal sulfides in the growth medium was determined by weight method. Sulfate and sulfur-reducing bacteria were resistant to 2.0 mM Pb(NO3)2, 2.5 mM CuCl2, 2.5 mM FeCl2 × 4H2O and 2.0 mM MnCl2 × 4H2O, therefore they are promising for the development of biotechnologies for the purification of water resources contaminated by sulfur and metal compounds. When present in a medium with sulfates or sulfur of 1.0–1.5 mM lead, cuprum (II), iron (II) or manganese (II) ions, they almost completely bind with the H2S produced by bacteria in the form of insoluble sulfides, which confirms the negative results of qualitative reactions to their presence in the cultural liquid.

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Zheng, Rikuan, Shimei Wu, and Chaomin Sun. "Pseudodesulfovibrio cashew sp. Nov., a Novel Deep-Sea Sulfate-Reducing Bacterium, Linking Heavy Metal Resistance and Sulfur Cycle." Microorganisms 9, no. 2 (February 19, 2021): 429. http://dx.doi.org/10.3390/microorganisms9020429.

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Sulfur cycling is primarily driven by sulfate reduction mediated by sulfate-reducing bacteria (SRB) in marine sediments. The dissimilatory sulfate reduction drives the production of enormous quantities of reduced sulfide and thereby the formation of highly insoluble metal sulfides in marine sediments. Here, a novel sulfate-reducing bacterium designated Pseudodesulfovibrio cashew SRB007 was isolated and purified from the deep-sea cold seep and proposed to represent a novel species in the genus of Pseudodesulfovibrio. A detailed description of the phenotypic traits, phylogenetic status and central metabolisms of strain SRB007 allowed the reconstruction of the metabolic potential and lifestyle of a novel member of deep-sea SRB. Notably, P. cashew SRB007 showed a strong ability to resist and remove different heavy metal ions including Co2+, Ni2+, Cd2+ and Hg2+. The dissimilatory sulfate reduction was demonstrated to contribute to the prominent removal capability of P. cashew SRB007 against different heavy metals via the formation of insoluble metal sulfides.

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Roussel, Jimmy, A. J. Murray, John Rolley, D. Barrie Johnson, and L. E. Macaskie. "Biosynthesis of Zinc Sulfide Quantum Dots Using Waste Off-Gas from Metal Bioremediation Process." Advanced Materials Research 1130 (November 2015): 555–59. http://dx.doi.org/10.4028/www.scientific.net/amr.1130.555.

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Dissimilatory reduction of sulfate, mediated by various species of sulfate-reducing bacteria (SRB), can be used to remediate acid mine drainage (AMD). Hydrogen sulfide (H2S/HS-) generated by SRB can be used to remove toxic metals from AMD as sulfide biominerals. For this, SRB are usually housed in separate reactor vessels to those where metal sulfides are generated; H2S is delivered to AMD-containing vessels in solution or as a gas. This allows more controlled separation of metal precipitation and facilitates enhanced process control. Industries such as optoelectronics use quantum dots (QDs) in, for example, light emitting diodes and solar photovoltaics. QDs are nanocrystals with semiconductor bands that allow them to absorb light and re-emit it intensely at specific wavelength couples. Small nanoparticles have the possibility to get electrons shifted to a higher energy and then emit light during the relaxation phase. The QD elemental composition and the presence of doping agent determines its electronic band gaps and can be used to tune the QD to desired emission wavelengths. Traditional QD production at scale is costly and/or complex. Waste H2S gas from growth of SRB has been used to make zinc sulfide QDs which are indistinguishable from ’classically’ prepared counterparts with respect to their physical and optical properties. Clean recycling of minewater bioremediation process waste gas into high value QD product is described.

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Thériault, Robert D., Sarah-Jane Barnes, and Mark J. Severson. "The influence of country-rock assimilation and silicate to sulfide ratios (R factor) on the genesis of the Dunka Road Cu – Ni – platinum-group element deposit, Duluth Complex, Minnesota." Canadian Journal of Earth Sciences 34, no. 4 (April 1, 1997): 375–89. http://dx.doi.org/10.1139/e17-033.

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The Dunka Road deposit is one of several Cu – Ni – platinum-group element (PGE) sulfide occurrences found along the northwestern margin of the Duluth Complex, where the host troctolitic rocks are in contact with metasedimentary rocks of the Animikie Group. Magma contamination through assimilation of sulfidic argillaceous country rocks is generally recognized as having played a key role in the genesis of the mineralization. Three main types of disseminated sulfide mineralization have been identified within the Dunka Road deposit: (i) norite-hosted sulfides, (ii) troctolite-hosted sulfides, and (iii) PGE-rich sulfide horizons. The norite-hosted sulfides are found either adjacent to country-rock xenoliths or near the basal contact. The troctolite-hosted sulfides form the bulk of the deposit, and occur throughout the lower 250 m of the intrusion. The PGE-rich sulfide horizons are typically localized directly beneath ultramafic layers. The composition of the different types of sulfide occurrences is modelled using Cu/Pd ratios. It is shown that each type results from the interplay of two main parameters, namely the degree of magma contamination and the silicate magma to sulfide melt ratio (R factor). The norite-hosted sulfides formed at low R factors and high degrees of contamination, as expressed by their PGE-depleted nature, low Se/S ratios, and elevated content in pyrrhotite and arsenide minerals. The troctolite-hosted sulfides formed at moderate R factors and small degrees of contamination, as shown by their moderate PGE content and mantle-like Se/S ratios. Finally, the PGE-rich sulfide horizons are modelled using elevated R factors from an uncontaminated parental magma, which is substantiated by their elevated noble metal content and Se/S ratios, and low pyrrhotite to precious metal sulfide ratio.

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Edgcomb, Virginia P., Stephen J. Molyneaux, Mak A. Saito, Karen Lloyd, Simone Böer, Carl O. Wirsen, Michael S. Atkins, and Andreas Teske. "Sulfide Ameliorates Metal Toxicity for Deep-Sea Hydrothermal Vent Archaea." Applied and Environmental Microbiology 70, no. 4 (April 2004): 2551–55. http://dx.doi.org/10.1128/aem.70.4.2551-2555.2004.

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ABSTRACT The chemical stress factors for microbial life at deep-sea hydrothermal vents include high concentrations of heavy metals and sulfide. Three hyperthermophilic vent archaea, the sulfur-reducing heterotrophs Thermococcus fumicolans and Pyrococcus strain GB-D and the chemolithoautotrophic methanogen Methanocaldococcus jannaschii, were tested for survival tolerance to heavy metals (Zn, Co, and Cu) and sulfide. The sulfide addition consistently ameliorated the high toxicity of free metal cations by the formation of dissolved metal-sulfide complexes as well as solid precipitates. Thus, chemical speciation of heavy metals with sulfide allows hydrothermal vent archaea to tolerate otherwise toxic metal concentrations in their natural environment.

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Zheng, He Hua, Hui Li Liu, Quan Bi Huang, and Qin Hua Li. "The Release Mechanism of Heavy Metals from Sulfide Tailings." Advanced Materials Research 1073-1076 (December 2014): 833–37. http://dx.doi.org/10.4028/www.scientific.net/amr.1073-1076.833.

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The sulfide tailings is the main type of non-ferrous metals mine tailings, in which the sulfides could react with air, rain water and microorganism, etc. and then release some ions through a series of complex chemical interactions. The heavy metal ions leaching from tailings will cause serious pollution to the environment of mine region. The release mechanisms and effect factors of heavy metals ions from sulfide tailings are summarized in this paper.

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Calvert, Giles, Anna H. Kaksonen, Ka Yu Cheng, Jonovan Van Yken, Barbara Chang, and Naomi J. Boxall. "Recovery of Metals from Waste Lithium Ion Battery Leachates Using Biogenic Hydrogen Sulfide." Minerals 9, no. 9 (September 17, 2019): 563. http://dx.doi.org/10.3390/min9090563.

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Lithium ion battery (LIB) waste is increasing globally and contains an abundance of valuable metals that can be recovered for re-use. This study aimed to evaluate the recovery of metals from LIB waste leachate using hydrogen sulfide generated by a consortium of sulfate-reducing bacteria (SRB) in a lactate-fed fluidised bed reactor (FBR). The microbial community analysis showed Desulfovibrio as the most abundant genus in a dynamic and diverse bioreactor consortium. During periods of biogenic hydrogen sulfide production, the average dissolved sulfide concentration was 507 mg L−1 and the average volumetric sulfate reduction rate was 278 mg L−1 d−1. Over 99% precipitation efficiency was achieved for Al, Ni, Co, and Cu using biogenic sulfide and NaOH, accounting for 96% of the metal value contained in the LIB waste leachate. The purity indices of the precipitates were highest for Co, being above 0.7 for the precipitate at pH 10. However, the process was not selective for individual metals due to simultaneous precipitation and the complexity of the metal content of the LIB waste. Overall, the process facilitated the production of high value mixed metal precipitates, which could be purified further or used as feedstock for other processes, such as the production of steel.

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Yang, Yang, Yifei Xie, Xudong Li, Jingchao Zhou, and Jingwei Liu. "Microscopic characteristic of biological iron sulfide composites during the generation process and the association with treatment effect on heavy metal wastewater." Water Science and Technology 70, no. 7 (August 25, 2014): 1292–97. http://dx.doi.org/10.2166/wst.2014.372.

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Heavy metal pollution is a serious environmental concern worldwide, resulting in both environmental and human harm. Recently, studies have shown that environmental biotechnologies based on sulfate reduction offer a potential for removal of toxic heavy metals. Biological iron sulfide composites are iron sulfide compounds generated in situ by sulfate-reducing bacteria. In this study, microscopic morphological changes during the composites' generation process were studied, and the effect of biological iron sulfide composites in different generation phases on treatment of heavy metal wastewater was investigated to establish the correlation between macro-effect and micro-properties. The results revealed that the generation process of biological iron sulfide composites occurs in three phases: the formation phase, stationary phase, and agglomeration phase. The stationary phase can be divided into a pre-stationary phase and post-stationary phase. It was found that the best treatment time for Cr6+ is in the pre-stationary phase, while the best treatment time for Cu2+and Cd2+ is in the post-stationary phase. The results of this study further prove the benefits of treatment of heavy metal wastewater using biological sulfide composites and provide theoretical guidance in practical applications.

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Gabelchenko, N. I., E. Y. Karpova, A. I. Gabelchenko, and A. P. Ryshko. "RESEARCH OF THE METAL WORKING IN THE ENVIRONMENTS CAUSING SODIUM HYDROGEN CRACKING." IZVESTIA VOLGOGRAD STATE TECHNICAL UNIVERSITY, no. 7(242) (July 29, 2020): 28–33. http://dx.doi.org/10.35211/1990-5297-2020-7-242-28-33.

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The results of a study of a metal working in environments causing hydrogen sulfide cracking are presented. The previously studied steels were induced in a hydrogen sulfide-containing medium under the action of tensile stresses in the metal of the samples. It has been established that characteristic defects in the form of bubbles and blisters are formed on the surface of metals. A study of microstructures showed that cracks originate at the boundary between pearlite and ferrite grains and on the streaked sulfide phase of the FeS · MnS type. Disclosure of the boundary of pearlitic and ferrite grains is due to their surface contamination with microimpurities. The results of the analysis for inclusions show that 20YuCH steel is much cleaner in inclusions than American steel of the type steel 20, and sulfides are more dispersed and coagulated, while a significant part of the sulfur is bound by cerium. This explains the best resistance of steel 20YUCH against hydrogen sulfide cracking.

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Bauch, Christopher G., and Curtis E. Johnson. "The preparation of metal sulfides and organo-metal sulfides from metal alkyls and hydrogen sulfide." Inorganica Chimica Acta 164, no. 2 (October 1989): 165–69. http://dx.doi.org/10.1016/s0020-1693(00)83218-1.

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Jambor, J. L., D. K. Nordstrom, and C. N. Alpers. "Metal-sulfate Salts from Sulfide Mineral Oxidation." Reviews in Mineralogy and Geochemistry 40, no. 1 (January 1, 2000): 303–50. http://dx.doi.org/10.2138/rmg.2000.40.6.

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Chaumba, Jeff B., and Caston T. Musa. "Formation of the main sulfide zone at Unki Mine, Shurugwi Subchamber of the Great Dyke, Zimbabwe: Constraints from petrography and sulfide compositions." Geosphere 16, no. 2 (January 16, 2020): 685–710. http://dx.doi.org/10.1130/ges02150.1.

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Abstract The major platinum group element (PGE) occurrence in the Great Dyke of Zimbabwe, the main sulfide zone, is a tabular stratabound layer hosted in pyroxenites, and it is broadly similar in form throughout the length of the Great Dyke. We conducted a petrographic and sulfide composition study on a sulfide-enriched zone from the contact of the mafic sequence–ultramafic sequence through the main sulfide zone at Unki Mine in the Shurugwi Subchamber to its underlying footwall rocks to place some constraints on the origin of the rocks. Pyrrhotite, pentlandite, chalcopyrite, and pyrite are the base metal sulfides that were encountered during the study. Pyrrhotite, pentlandite, and chalcopyrite typically occurred as inclusions in both primary (orthopyroxene, plagioclase, and clinopyroxene) and secondary (amphibole and chlorite) silicate phases, whereas pyrite was observed in only three samples, where it occurred in association with pyrrhotite. The concentrations of PGEs in the base metal sulfides were nearly all at or below minimum detection limits. The intercumulus nature of some of these sulfides in the investigated sequence suggests that they were likely formed during the crystallization history of these rocks. The occurrence of pyrite, which we interpret to be an alteration phase, suggests that a late-stage event, likely formed during hydrothermal alteration, helped to concentrate the mineralization at Unki Mine. In some cases, however, these sulfides occur partially surrounding some chromite and silicate phases. Thus, some sulfides in the Unki Mine area were likely formed early in the crystallization history of the Great Dyke, whereas others were formed late during hydrothermal processes. Low concentrations of PGEs such as platinum (Pt), palladium (Pd), and rhodium (Rh) in base metal sulfides imply that the PGEs in the main sulfide zone and Unki Mine are hosted either in silicates and/or platinum group minerals. Very low Co contents in pentlandites in the rocks under investigation are interpreted to imply that very limited Fe substitution by Co, and also of Ni by Co, occurred. Broadly comparable trends, with minor variations of Fe in pyrrhotite, of Co and Ni in pentlandite, and of Cu in chalcopyrite, for example, likely reflect magmatic processes. The concentrations of these metals in base metal sulfides vary sympathetically, indicating that their original magmatic signatures were subsequently affected by hydrothermal fluids. The spiked pattern displayed by the variations in the percent modal proportions of the base metal sulfides across the entire investigated stratigraphic section is interpreted to reflect remobilization of the sulfides during hydrothermal alteration. Depletions in some elements, which occur near the base and at the top of the investigated succession, are likely a result of this hydrothermal alteration.

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Ferreira, Amanda D., Hermano M. Queiroz, Maira P. Kaneagae, Gabriel N. Nóbrega, Xosé L. Otero, Ângelo F. Bernardino, and Tiago O. Ferreira. "Gypsum Amendment Induced Rapid Pyritization in Fe-Rich Mine Tailings from Doce River Estuary after the Fundão Dam Collapse." Minerals 11, no. 2 (February 14, 2021): 201. http://dx.doi.org/10.3390/min11020201.

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Mine tailings containing trace metals arrived at the Doce River estuary, after the world’s largest mine tailings disaster (the Mariana disaster) dumped approximately 50 million m3 of Fe-rich tailings into the Doce River Basin. The metals in the tailings are of concern because they present a bioavailability risk in the estuary as well as chronic exposure hazards. Trace metal immobilization into sulfidic minerals, such as, pyrite, plays a key role in estuarine soils; however, this process is limited in the Doce River estuarine soil due to low sulfate inputs. Thus, to assess the use of gypsum amendment to induce pyritization in deposited tailings, a mesocosm experiment was performed for 35 days, with vinasse added as carbon source and doses of gypsum (as a sulfate source). Chemical and morphological evidence of Fe sulfide mineral precipitation was observed. For instance, the addition of 439 mg of S led to the formation of gray and black spots, an Fe2+ increase and decrease in sulfides in the solution, an increase in pyritic Fe, and a greater Pb immobilization by pyrite at the end of the experiment. The results show that induced pyritization may be a strategy for remediating metal contamination at the Doce River estuary.

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Kromah, Varney, and Guanghui Zhang. "Aqueous Adsorption of Heavy Metals on Metal Sulfide Nanomaterials: Synthesis and Application." Water 13, no. 13 (July 1, 2021): 1843. http://dx.doi.org/10.3390/w13131843.

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Heavy metals pollution of aqueous solutions generates considerable concerns as they adversely impact the environment and health of humans. Among the remediation technologies, adsorption with metal sulfide nanomaterials has proven to be a promising strategy due to their cost-effective, environmentally friendly, surface modulational, and amenable properties. Their excellent adsorption characteristics are attributed to the inherently exposed sulfur atoms that interact with heavy metals through various processes. This work presents a comprehensive overview of the sequestration of heavy metals from water using metal sulfide nanomaterials. The common methods of synthesis, the structures, and the supports for metal sulfide nano-adsorbents are accentuated. The adsorption mechanisms and governing conditions and parameters are stressed. Practical heavy metal remediation application in aqueous media using metal sulfide nanomaterials is highlighted, and the existing research gaps are underscored.

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Ashirov, Makhsud, Ibragimov Rustam Kholikulovich, and Jasur Rakhmatullaev. "Koytash Deposit As A Prospective Object Of Uzbekistan For Expanding Resources Of Wollastonite, Precious Metals And Other Associated Elements." American Journal of Applied sciences 03, no. 01 (January 22, 2021): 25–29. http://dx.doi.org/10.37547/tajas/volume03issue01-06.

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The article discusses complex and conjugated formation of wollostonite, sulfide-rare metal and silver-base polymetallic ores of Koytash deposit. Forms recommended for co-extraction, mineral composition and elements-impurities of them have been revealed. These data on rare-metal sulfide and sulfide-polymetallic ores of Koytash skarn-rare metal deposit proves its prospects in extraction of both rare metal and noble metals, bismuth and wollastonite.

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LIU, JUN, and DONGFENG XUE. "A GENERAL TEMPLATE-FREE AND SURFACTANT-FREE SOLUTION-BASED ROUTE TOWARDS DENDRITIC TRANSITION-METAL SULFIDE NANOSTRUCTURES." Modern Physics Letters B 23, no. 31n32 (December 30, 2009): 3777–83. http://dx.doi.org/10.1142/s021798490902182x.

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A template-free and surfactant-free hydrothermal method has been successfully developed to fabricate hierarchically dendritic metal sulfides ( PbS and CdS ). It has been found that the reaction temperature play important roles in the formation of well-defined sulfide dendritic nanostructures. A possible mechanism for the formation of present dendrites was proposed. The as-obtained transition-metal sulfide dendritic nanostructures may bring wide applications in optics, electricity, gas sensors, and other related fields. The synthetic route present in this work provides a new principle for the designing synthesis of dendritic metal sulfide nanomaterials and can be regarded as a general way to fabricate other metal chalcogenide materials.

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Saputra, Beny, Agus Sutanto, Mia Cholvistaria, Suprayitno Suprayitno, and Nala Rahmawati. "IDENTIFIKASI BAKTERI PEREDUKSI SULFAT PADA KAWAH AIR PANAS NIRWANA SUOH LAMPUNG BARAT." BIOLOVA 2, no. 2 (August 30, 2021): 122–27. http://dx.doi.org/10.24127/biolova.v2i2.1089.

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Abstrak: Bakteri pereduksi sulfat atau Sulfate-reducing bacteria (SRB) adalah jenis bakteri obligat anaerob kemolitrotof memanfaatkan donor electron H2. Kemampuan SRB mereduksi sulfat menjadi sulfida mampu mengendapkan logam toksik meliputi Cd, Cu, dan Zn sebagai logam sulfida. SRB memerlukan substrat organik seperti asam piruvat yang dihasilkan oleh aktivitas anaerob lainnya. Mekanisme SRB dalam melakukan reduksi sulfat, sulfat digunakan sebagai sumber energi sebagai akseptor elektron dan menggunakan sumber karbon (C) sebagai donor elekton dalam metabolisme dan bahan penyusun sel. Pada kondisi anaerob bahan organik akan berperan sebagai donor elektron. Pembentukan senyawa sulfida melalui proses reduksi yang ditandai oleh penambahan elektron dari bahan organik yang menyebabkan turunnya konsentrasi sulfat dan naiknya pH lingkungan. SRB pada kawah air panas nirwana ini hidup secara anaerob pada suhu lingkungan 600C - 1000C dengan pH 7,4 tingkat kekeruhan air cukup keruh dan kandungan air yang mengandung blerang dengan indikator bau seperti telur busuk dan lingkungan sekitar terdiri dari sedimen batu kapur. Abstract : Sulfate-reducing bacteria (BPS) is a type of chemolithotroph obligate anaerobic bacteria that utilize H2 electron donors. The ability of BPS to reduce sulfate to sulfide is able to precipitate toxic metals including Cd, Cu, and Zn as metal sulfides. BPS requires organic substrates such as pyruvic acid which is produced by other anaerobic activities. The BPS mechanism in reducing sulfate, sulfate is used as an energy source as an electron acceptor and uses a carbon source (C) as an electron donor in metabolism and cell building material. Under anaerobic conditions, organic matter will act as an electron donor. The formation of sulfide compounds through a reduction process is characterized by the addition of electrons from organic matter which causes a decrease in sulfate concentration and an increase in environmental pH. BPS in this nirvana hot spring crater lives anaerobically at an environmental temperature of 600C - 1000C with a pH of 7.4 the level of turbidity of the water is quite cloudy and the water content contains sulfur with an indicator of smell like rotten eggs and the surrounding environment consists of limestone sediments

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Junussov, Medet, Ferenc Mádai, and Bánhidi Olivér. "Sequential extraction of carbonaceous siltstone rock for multi-element analysis by ICP OES." Contemporary Trends in Geoscience 7, no. 2 (December 1, 2018): 145–52. http://dx.doi.org/10.2478/ctg-2018-0010.

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Abstract The carbonaceous siltstone rock material is a disseminated sulfide-rich sedimentary rock from a sediment-hosted gold deposit of Bakyrchik. The Bakyrchik deposit is located in Eastern Kazakhstan, which includes in Qalba gold province. The main purpose of this paper is a demonstration on chemical extraction of heavy metals from the carbonaceous siltstone rock and detection of its elemental concentrations. In the work was used a rock sample from the deposit which is a sericizited carbonaceous-siltstone rock. In sequential extraction method was selected four stages such as water soluble fraction (reaction with deionized water) for extraction of water soluble metals, reducible metal fraction (reaction with hydroxyl ammonium chloride) for extracting all reducible metals, organics and sulfides (reaction with hydrogen peroxide) for dissolution of organics and copper sulfide, and extraction of metal oxides and residual fraction (reaction with aqua regia) for extracting of all remaining metals. The paper comprises analytical methods for research outlooks. They are X-Ray Diffraction (determination of mineralogical composition), X-Ray Fluorescence (determination of chemical composition) and Inductively Coupled Plasma – Optical Emission Spectrometry (determination of heavy metal concentrations).

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van der Graaf, Charlotte M., Javier Sánchez-España, Iñaki Yusta, Andrey Ilin, Sudarshan A. Shetty, Nicole J. Bale, Laura Villanueva, Alfons J. M. Stams, and Irene Sánchez-Andrea. "Biosulfidogenesis Mediates Natural Attenuation in Acidic Mine Pit Lakes." Microorganisms 8, no. 9 (August 21, 2020): 1275. http://dx.doi.org/10.3390/microorganisms8091275.

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Acidic pit lakes are abandoned open pit mines filled with acid mine drainage (AMD)—highly acidic, metalliferous waters that pose a severe threat to the environment and are rarely properly remediated. Here, we investigated two meromictic, oligotrophic acidic mine pit lakes in the Iberian Pyrite Belt (IPB), Filón Centro (Tharsis) (FC) and La Zarza (LZ). We observed a natural attenuation of acidity and toxic metal concentrations towards the lake bottom, which was more pronounced in FC. The detection of Cu and Zn sulfides in the monimolimnion of FC suggests precipitation of dissolved metals as metal sulfides, pointing to biogenic sulfide formation. This was supported by microbial diversity analysis via 16S rRNA gene amplicon sequencing of samples from the water column, which showed the presence of sulfidogenic microbial taxa in FC and LZ. In the monimolimnion of FC, sequences affiliated with the putative sulfate-reducing genus Desulfomonile were dominant (58%), whereas in the more acidic and metal-enriched LZ, elemental sulfur-reducing Acidianus and Thermoplasma spp., and disproportionating Desulfocapsa spp. were more abundant. Furthermore, the detection of reads classified as methanogens and Desulfosporosinus spp., although at low relative abundance, represents one of the lowest pH values (2.9 in LZ) at which these taxa have been reported, to our knowledge. Analysis of potential biomarker lipids provided evidence that high levels of phosphocholine lipids with mixed acyl/ether glycerol core structures were associated with Desulfomonile, while ceramide lipids were characteristic of Microbacter in these environments. We propose that FC and LZ function as natural bioremediation reactors where metal sulfide precipitation is mediated by biosulfidogenesis starting from elemental sulfur reduction and disproportionation at an early stage (LZ), followed by sulfate reduction at a later stage (FC).

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Karna, Ranju, Ganga Hettiarachchi, Joy Van Nostrand, Tong Yuan, Charles Rice, Yared Assefa, and Jizhong Zhou. "Microbial Population Dynamics and the Role of Sulfate Reducing Bacteria Genes in Stabilizing Pb, Zn, and Cd in the Terrestrial Subsurface." Soil Systems 2, no. 4 (November 3, 2018): 60. http://dx.doi.org/10.3390/soilsystems2040060.

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Milling and mining metal ores are major sources of toxic metals contamination. The Spring River and its tributaries in southeast Kansas are contaminated with Pb, Zn, and Cd because of 120 years of mining activities. Trace metal transformations and cycling in mine waste materials greatly influence their mobility and toxicity and they affect both plant productivity and human health. It has been hypothesized that under reduced conditions in sulfate-rich environments, these metals can be transformed into their sulfide forms, thus limiting mobility and toxicity. We studied biogeochemical transformations of Pb, Zn, and Cd in flooded subsurface mine waste materials, natural or treated with organic carbon (OC), and/or sulfur (S), by combining advanced microbiological and X-ray spectroscopic techniques to determine the effects of treatments on the microbial community structure and identify the dominant functional genes that are involved in the biogeochemical transformations, especially metal sulfide formation over time. Samples collected from medium-, and long-term submerged columns were used for microarray analysis via functional gene array (GeoChip 4.2). The total number of detected gene abundance decreased under long-term submergence, but major functional genes abundance was enhanced with OC-plus-S treatment. The microbial community exhibited a substantial change in structure in response to OC and S addition. Sulfate-reducing bacteria genes dsrA/B were identified as key players in metal sulfide formation via dissimilatory sulfate reduction. Uniqueness of this study is that microbial analyses presented here in detail are in agreement with molecular-scale synchrotron-based X-ray data, supporting that OC-plus-S treatment would be a promising strategy for reducing metal toxicity in mine waste materials in the subsurface environment.

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Yamamoto, T., A. Taniguchi, S. Dev, E. Kubota, K. Osakada, and K. Kubota. "New organosols of nickel sulfides, palladium sulfides, manganese sulfide, and mixed metal sulfides and their use in preparation of semiconducting polymer-metal sulfide composites." Colloid & Polymer Science 269, no. 10 (October 1991): 969–71. http://dx.doi.org/10.1007/bf00657425.

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26

BURCH, R. "Metal sulfide-support interactions." Journal of Catalysis 97, no. 2 (February 1986): 385–89. http://dx.doi.org/10.1016/0021-9517(86)90010-2.

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27

Moreau, John W., Robert A. Zierenberg, and Jillian F. Banfield. "Diversity of Dissimilatory Sulfite Reductase Genes (dsrAB) in a Salt Marsh Impacted by Long-Term Acid Mine Drainage." Applied and Environmental Microbiology 76, no. 14 (May 14, 2010): 4819–28. http://dx.doi.org/10.1128/aem.03006-09.

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ABSTRACT Sulfate-reducing bacteria (SRB) play a major role in the coupled biogeochemical cycling of sulfur and chalcophilic metal(loid)s. By implication, they can exert a strong influence on the speciation and mobility of multiple metal(loid) contaminants. In this study, we combined DsrAB gene sequencing and sulfur isotopic profiling to identify the phylogeny and distribution of SRB and to assess their metabolic activity in salt marsh sediments exposed to acid mine drainage (AMD) for over 100 years. Recovered dsrAB sequences from three sites sampled along an AMD flow path indicated the dominance of a single Desulfovibrio species. Other major sequence clades were related most closely to Desulfosarcina, Desulfococcus, Desulfobulbus, and Desulfosporosinus species. The presence of metal sulfides with low δ34S values relative to δ34S values of pore water sulfate showed that sediment SRB populations were actively reducing sulfate under ambient conditions (pH of ∼2), although possibly within less acidic microenvironments. Interestingly, δ34S values for pore water sulfate were lower than those for sulfate delivered during tidal inundation of marsh sediments. 16S rRNA gene sequence data from sediments and sulfur isotope data confirmed that sulfur-oxidizing bacteria drove the reoxidation of biogenic sulfide coupled to oxygen or nitrate reduction over a timescale of hours. Collectively, these findings imply a highly dynamic microbially mediated cycling of sulfate and sulfide, and thus the speciation and mobility of chalcophilic contaminant metal(loid)s, in AMD-impacted marsh sediments.

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28

Kurmangalieva, Anna I., Lyubov' A. Anikanova, Ol'ga V. Volkova, Alexandr I. Kudyakov, Yurij S. Sarkisov, and Yurij A. Abzaev. "ACTIVATION OF HARDENING PROCESSES OF FLUOROGYPSUM COMPOSITIONS BY CHEMICAL ADDITIVES OF SODIUM SALTS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 63, no. 8 (June 24, 2020): 73–80. http://dx.doi.org/10.6060/ivkkt.20206308.6137.

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The article is devoted to modifications of fluorogypsum compositions by chemical additives of sodium salts in the form of sulfate, sulfite and sodium sulfide, as well as their combined effect on the kinetics of structure formation processes. Technological, ecological and technical aspects of utilization of fluorogypsum compositions activated by additives were investigated. Experiments have shown that an up to 3% increase in the amount of sodium sulfite additive leads to an increase in the compressive strength of samples at early stages of hardening (up to 14 days), whereas utilization of sodium sulfate additive forms a crystallization structure at later stages. Therefore, it is rational to combine sulfate and sodium sulfite additives in an amount not exceeding 3% of the binder’s weight. The binder hardening structure formation with sodium sulfide addition at early stages results in production of additional structure-forming substances such as calcium sulfide. The mechanism of differentiated application of individual sulfate and sodium sulfite additives allowed to suggest that combined sulfate and sulfite additives utilization seems to be the most rational decision, due to the fact that it is not a mere individual additives’ combination, but a buffer mixture, which means that the mechanism of such mixtures influence will be subject to the buffer action. The system will maintain a strictly defined pH range constancy, which determines stability of new growths, forming the hardening structure. However, using sodium sulfide as an additive and studying its impact on fluoroanhydrate compositions structure formation in both individual and combined with sodium sulfite and sodium sulfate forms appears to be as much reasonable. The combined Na2SO3-Na2SO4 additive activates hardening processes both at early and late stages. At the same time, columnar structures growing from the center to the periphery are formed, as indicated by electron-microscopic studies. Their growth stems from concentration gradient of SO42-- and SO32-- ions, which is in complete agreement with the other research data and is typical for both metal melts and cement systems solidification process.

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Gould, J. P., F. G. Pohland, and W. H. Cross. "Chemical Controls on the Fate of Mercury and Lead Codisposed with Municipal Solid Waste." Water Science and Technology 21, no. 8-9 (August 1, 1989): 833–43. http://dx.doi.org/10.2166/wst.1989.0286.

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Mercury and lead were among several toxic metals codisposed in test lysimeters with municipal solid waste. Results of analysis of leachates from these landfills during the acid phase of landfill operation have indicated that control of mercury in these systems is a consequence of reduction of divalent mercury to neutral mercury metal. This process was found to occur whether sulfide was present or not. Dissolved mercury in these leachates will exist virtually entirely as chloride complexes. Control of lead solubility was dependent on the presence or absence of sulfide. In the presence of sulfide lead would precipitate as the sulfide while in its absence, the controlling solid was the sulfate. Soluble lead speciation involved significant fractions of both chloride and sulfate complexes. While sulfide has not been detected directly in these systems, levels necessary to control lead solubility were so low as to be indetectable by available methodology and thus its involvement cannot be precluded. Since some circumstantial evidence supportive of sulfate control has been obtained, the complete elucidation of chemical control mechanisms in these systems is not possible.

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30

Li, Guangshi, Xiaolu Xiong, Liping Wang, Lang Che, Lizhen Wei, Hongwei Cheng, Xingli Zou, et al. "Sulfation Roasting of Nickel Oxide–Sulfide Mixed Ore Concentrate in the Presence of Ammonium Sulfate: Experimental and DFT Studies." Metals 9, no. 12 (November 25, 2019): 1256. http://dx.doi.org/10.3390/met9121256.

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Sulfation roasting, a common activation technique, is a potential method for cleaner production of nickel from complex low-grade ores. In this study, nickel oxide–sulfide mixed ore concentrate was roasted with the addition of ammonium sulfate under a static air atmosphere, and the roasted products were leached by water, in order to evaluate the extraction of metals. The ammonium sulfate activation roasting was investigated thoroughly and systematically by thermogravimetry–differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. Particularly, the interface sulfation behavior and path were studied by the density functional theory (DFT) method. The results showed that a large amount of nonferrous metal sulfate (70% Ni, 89% Co, and 90% Cu) was generated, while iron was almost entirely transformed into iron oxide under appropriate roasting conditions of adding ammonium sulfate at a mass ratio of 200%, heating to 650 °C at 10 °C/min, and holding for 120 min. It was found that activation of ammonium sulfate can take two different paths: one in which ammonium sulfate directly reacts with raw ores below 500 °C and the other in which the SO2 decomposed from sulfates (ammonium sulfate, intermediate ammonium ferric sulfate, and ferric sulfate) reacts with the intermediate metal sulfides (NiS and Cu2S). The interface sulfation mechanism of NiS and Cu2S was investigated deeply by DFT method, which showed that there are two paths of sulfation for NiS or Cu2S, and both of them are thermodynamically favored. Thus, a thorough and systematic investigation of ammonium sulfate activation roasting of nickel oxide–sulfide mixed ore is provided; this might be a potential basis for future industrial applications of ammonium sulfate activation roasting techniques in complex mineral metallurgy.

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Sethurajan, Manivannan, and Eric D. van Hullebusch. "Leaching and Selective Recovery of Cu from Printed Circuit Boards." Metals 9, no. 10 (September 24, 2019): 1034. http://dx.doi.org/10.3390/met9101034.

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Printed circuit boards (PCBs), a typical end-of-life electronic waste, were collected from an E-waste recycling company located in the Netherlands. Cu and precious metal concentration analyses of the powdered PCBs confirm that the PCBs are multimetallic in nature, rich, but contain high concentrations of Cu, Au, Ag, Pd, and Pt. Ferric sulfate concentration (100 mM), agitation speed (300 rpm), temperature (20 °C), and solid-to-liquid ratio (10 g·L−1) were found to be the optimum conditions for the maximum leaching of Cu from PCBs. The ferric sulfate leachates were further examined for selective recovery of Cu as copper sulfides. The important process variables of sulfide precipitation, such as lixiviant concentration and sulfide dosage were investigated and optimized 100 ppm of ferric sulfate and (copper:sulfide) 1:3 molar ratio, respectively. Over 95% of the dissolved Cu (from the multimetallic leachates) was selectively precipitated as copper sulfide under optimum conditions. The characterization of the copper sulfide precipitates by SEM-EDS analyses showed that the precipitates mainly consist of Cu and S. PCBs can thus be seen as a potential secondary resource for copper.

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32

Andalaluna, Lebong, and Masatoshi Sugioka. "Enhancemen Effect of Hydrogen Sulfide Over Metal Ion-Exchange Mesoporous Silicate FSM-16 for Acid Catalyzed Reactions." ASEAN Journal of Chemical Engineering 5, no. 1 (June 1, 2005): 76. http://dx.doi.org/10.22146/ajche.50166.

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The activity enhancement of metal ion-exchange mesoporous silicate FSM-16 (MeFSM-16) by sulfiding with hydrogen sulfide was studied using acid-catalyzed reactions, isomerization of I-butene, cis-2-butene and cyclopropane, as model reactions. It was revealed that the catalytic activities of MeFSM-16 for the acid-catalyzed reactions were remarkably enhanced after sulfiding with hydrogen sulfide. Moreover, it was observed that the optimum enhancement effect of hydrogen sulfide was obtained at the sulfiding temperature of 200°C. Infrared spectroscopic measurement of pyridine adsorption over sulfided MeFSM-16 showed that the activity enhancement of MeFSM-16 resulted in the generation of new Bronsted acid sites. Keywords: Metal ion-exchange, mesoporous silicate, hydrogen sulfide, and activity enhancement.

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33

Yên, Nguyễn Thị, and Kiều Thị Quỳnh Hoa. "Removal of lead by sulfate-reducing bacteria in anaerobic continuous stirred tank reactors." Vietnam Journal of Biotechnology 14, no. 3 (September 30, 2016): 557–61. http://dx.doi.org/10.15625/1811-4989/14/3/9873.

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Lead contaminated wastewater negatively impacts to living organisms as well as humans. In recent years, a highly promising biological process using the anaerobic production of sulfide ions by sulfate-reducing bacteria has presented itself as an alternative option for the removal of lead. This process is based on microbial utilization of electron donors, such as organic compounds (carbon sources), and sulfate as the terminal electron acceptor for sulfide production. The biogenic hydrogen sulfide reacts with dissolved heavy metals to form insoluble metal sulfide precipitates Removal of lead by an enriched consortium of sulfate-reducing bacteria (DM10) was evaluated sulfate reduction, sulfide production and lead precipitation. Four parallel anaerobic continuous stirred tank reactors (CSTR, V = 2L) (referred as R1 - R4) were fed with synthetic wastewater containing Pb2+ in the concentrations of 0, 100, 150 and 200 mg L-1 of lead and operated with a hydraulic retention time of 5 days for 40 days. The loading rates of each metal in R1- R4 were 0, 20, 30 and 40 mg L-1 d-1, respectively. The results showed that there was no inhibition of SRB growth and that lead removal efficiencies of 99-100% for Pb2+ were achieved in R2 (100 mg L-1) and R3 (150 mg L-1) throughout the experiment. For the highest lead concentration of 200 mg L-1, a decrease in efficiency of removal (from 100 to 96%) was observed at the end of the experiment. The obtained result of this study might help for a better control operation and performance improvements of reactors.

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Hwang, Eunseo, Yoonsu Park, Jongbae Kim, Taejong Paik, and Don-Hyung Ha. "Facile Sulfurization under Ambient Condition with Na2S to Fabricate Nanostructured Copper Sulfide." Nanomaterials 11, no. 9 (September 6, 2021): 2317. http://dx.doi.org/10.3390/nano11092317.

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The sulfurization reaction was investigated as a promising fabrication method for preparing metal sulfide nanomaterials. Traditional sulfurization processes generally require high vacuum systems, high reaction temperatures, and toxic chemicals, utilizing complicated procedures with poor composition and morphology controllability. Herein, a facile method is reported for synthesizing nanostructured copper sulfide using a sulfurization reaction with Na2S at room temperature under non-vacuum conditions. Moreover, we demonstrate that the morphology, composition, and optical properties of nanostructured copper sulfides could be controlled by the Na2S solution concentration and the reaction time. Nanostructured copper sulfides were synthesized in nanospheres, nanoplates, and nanoplate-based complex morphologies with various oxidation states. Furthermore, by comparing the optical properties of nanostructured copper sulfides with different oxidation states, we determined that reflectivity in the near infrared (NIR) region decreases with increasing oxidation states. These results reveal that the Na2S solution concentration and reaction time are key factors for designing nanostructured copper sulfides, providing new insights for synthesis methods of metal sulfide nanomaterials.

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35

Yamamoto, Takakazu, Etsuo Kubota, Atsushi Taniguchi, Somanath Dev, Kuniaki Tanaka, Kohtaro Osakada, and Masao Sumita. "Electrically conductive metal sulfide-polymer composites prepared by using organosols of metal sulfides." Chemistry of Materials 4, no. 3 (May 1992): 570–76. http://dx.doi.org/10.1021/cm00021a015.

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36

Bewtra, J. K., N. Biswas, W. D. Henderson, and J. A. Nicell. "Recent Advances in Treatment of Selected Hazardous Wastes." Water Quality Research Journal 30, no. 1 (February 1, 1995): 115–26. http://dx.doi.org/10.2166/wqrj.1995.016.

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Abstract Horseradish peroxidase, once activated by hydrogen peroxide, initiates the oxidation of a wide variety of aromatic compounds. The products of this reaction undergo a non-enzymatic polymerization to form water insoluble aggregates which are easily separated from solution. This process shows great promise for removing aromatic compounds from industrial wastewaters which are not efficiently removed through conventional treatment methods. The capability of solubilized horseradish peroxidase in catalyzing the precipitation of phenols from solution in batch reactors is discussed. Studies have been conducted on the biological sulfate reduction process to remove metals from synthetic and actual industrial wastewaters. Under anaerobic conditions, bacteria of the genera Desulfovibrio and Desulfotomaculum produce hydrogen sulfide which reacts with metals to form metal sulfide precipitates. An anaerobic upflow fixed-film reactor with continuous flow was used to treat actual wastewater from a plating plant supplemented with lactate. The results indicate that soluble metals can be precipitated at efficiencies of up to 99%. The rates of organic conversion, sulfate reduction and metal removal have been found to be dependent on the hydraulic retention time.

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37

Selivanov, Evgeny N., O. V. Nechvoglod, and R. I. Gulyaeva. "Thermal Expansion of Copper and Nickel Sulfides and their Alloys." Defect and Diffusion Forum 334-335 (February 2013): 55–59. http://dx.doi.org/10.4028/www.scientific.net/ddf.334-335.55.

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Thermal expansion coefficients of metal sulfides and their alloys are important for technological processes calculations of sulfide processing materials, for example, the crystallization equipment of nickel and copper-nickel converter matte. The synthesized copper and nickel monosulfide, and nickel and copper-nickel matte have been used as the initial samples. Dilatometric analysis was carried out by dilatometer (Linseis L78 RITA). Differences in the values measured are accounted for by the synthesis samples facilities, the coexistence of several non-stoichiometric sulfide phases and interaction during heating. In the temperature 20-500°C range the coefficients of thermal expansion (α) for the sulfides of copper, nickel and their alloys are changed from 10.4 to 20.610-6 1/K. Changes in the value α are accounted for by phase transitions in sulfide samples at their heating. Considering the properties of the phase components are an additive it is shown the thermal expansion coefficient complex sulfide-metal alloys is possible to calculate.

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38

Hartmann, Nathaniel J., Guang Wu, and Trevor W. Hayton. "Activation of CS2 by a “masked” terminal nickel sulfide." Dalton Transactions 45, no. 37 (2016): 14508–10. http://dx.doi.org/10.1039/c6dt00885b.

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Activation of carbon disulfide (CS₂) by “masked” terminal nickel sulfide, [K(18-crown-6)][(L^tBu)Ni(S)], gives a trithiocarbonate complex. This result confirms the nucleophilicity of the sulfide ligand and expands the scope of reactivity for late metal sulfides.

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Yap, Pei Lay, Yow Loo Au Yoong, Muralithran G. Kutty, Olaf Timpe, Malte Behrens, and Sharifah Bee Abdul Hamid. "Facile Remediation Method of Copper Sulfide by Nitrogen Pre-Treatment." Advanced Materials Research 361-363 (October 2011): 1445–50. http://dx.doi.org/10.4028/www.scientific.net/amr.361-363.1445.

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The deactivation and destabilization of copper sulfide when exposed to an oxidizing environment has led to the economical concerns as this sulfidic material can be easily destroyed by a series of oxidation processes. A promising and effective remediation technique in limiting the contact between covellite (CuS) and oxygen has been developed using a simple, hassle-free, non-corrosive, and eco-friendly pre-treatment of nitrogen approach. This remediation technique is remarkably effective as various techniques such as powder XRD, EDX, elemental mapping, and TGA-MS analyses have confirmed that covellite prepared with the pre-treatment of nitrogen does not oxidize to any mixed phase compound. Meanwhile, the study also shows that covellite stored without the pre-treatment of nitrogen has transformed to a mixed phase of pentahydrate copper sulfate and covellite. Hence, this method can be practically exercised not only on covellite, but possibly on other metal sulfides which are prone to be attacked by oxygen and water molecules in oxidizing environment.

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40

Goodwin, A. M., H. G. Thode, C. L. Chou, and S. N. Karkhansis. "Chemostratigraphy and origin of the late Archean siderite–pyrite-rich Helen Iron Formation, Michipicoten belt, Canada." Canadian Journal of Earth Sciences 22, no. 1 (January 1, 1985): 72–84. http://dx.doi.org/10.1139/e85-006.

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The 2.7 Ga old Helen Iron Formation (HIF) with its uniquely large siderite–Pyrite orebody conformably overlies chemically altered rhyolite–dacite pyroclastic rocks, including an ottrelite-bearing alteration pipe, the product of exhalative venting in freshly accumulated pyroclastics. HIF, in turn, is conformably overlain by pillowed mafic lava flows.HIF internal stratigraphy is conformable from lower massive siderite–sulfide through middle sulfidic, carbonaceous chert, to upper magnetitic chert. Major- and trace-element and carbon- and sulfur-isotope data demonstrate cyclic fluctuations in chemical precipitation from early chemically complex to later chemically "simple" components.HIF development is attributed to seawater-charged volcanic exhalations in a transitory subaqueous cauldron subsidence basin. Volcanic exhalations contained (1) the main chemical components of HIF; (2) nutrients that triggered intense bacterial activity, the principal low-Eh-inducing agent; and (3) acidic components (e.g., HCI, HF), the principal low-pH-inducing agent. HIF carbonates (predominantly siderite) and sulfides (mainly pyrite) are of marine carbonate and marine sulfate origin, respectively. Organic activity was a vital catalyst in carbonate–sulfide precipitation. HIF is notably deficient in base and noble metals, thereby indicating low circulation–exhalation temperatures, in sharp contrast to contemporary hot, metal-rich geothermal brines at modern spreading ridge axes. This transient subaqueous late Archean volcanic environment, then, was unique in scale but not in kind.

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41

Hillerová, Eva, and Miroslav Zdražil. "Activity and selectivity of carbon-supported transition metal sulfides in simultaneous hydrodearomatization and hydrodesulfurization." Collection of Czechoslovak Chemical Communications 54, no. 10 (1989): 2648–56. http://dx.doi.org/10.1135/cccc19892648.

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Hydrodesulfurization (HDS) and hydrodearomatization (HYD) activities of carbon-supported sulfides of V, Cr, Mn, Fe, Co, Ni, Nb, Mo, Ru, Rh, Pd, W, Re, Ir, and Pt, and of the commercial Co-Mo/Al2O3 catalysts were evaluated. Simultaneous hydrodesulfurization of benzothiophene and hydrogenation of naphthalene to tetralin at pressure of 2 MPa were used as the model reaction. Platinum group metal sulfides and Re sulfide exhibited the highest HDS activity and Pd and Rh sulfides reached the activity of a good commercial Ni-Mo catalyst. Tha catalysts strongly differed in the selectivity of dihydrobenzothiophene formation during HDS; up to 55% of dihydrobenzothiophene was obtained over W sulfide, while Rh, Ni, Co-Mo and Ni-Mo catalysts produced less than 8% of it. The highest HYD activity exhibited platinum group metal sulfides; the best were Ir and Pt sulfides which were four times and three times more active than the commercial Ni-Mo catalyst, respectively. The selectivity HDA/HDS depend strongly on the type of transition metal. The sulfides of W, Ir and Pt were much more selective for HYD than the Ni-Mo catalyst, and the Co-Mo sample showed by far the lowest HDA/HDS selectivity.

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42

Rickard, D. "Metal Sulfide Complexes and Clusters." Reviews in Mineralogy and Geochemistry 61, no. 1 (January 1, 2006): 421–504. http://dx.doi.org/10.2138/rmg.2006.61.8.

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43

Donaldson, Laurie. "Improving sodium–metal sulfide batteries." Materials Today 20, no. 5 (June 2017): 224. http://dx.doi.org/10.1016/j.mattod.2017.04.023.

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44

Al-Farawati, Radwan, and Constant M. G. van den Berg. "Metal–sulfide complexation in seawater." Marine Chemistry 63, no. 3-4 (January 1999): 331–52. http://dx.doi.org/10.1016/s0304-4203(98)00056-5.

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45

Kudryashov, N. A., A. A. Kutukov, and E. A. Mazur. "Metal hydrogen sulfide superconducting temperature." Novel Superconducting Materials 3, no. 1 (January 1, 2017): 1–5. http://dx.doi.org/10.1515/nsm-2017-0001.

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AbstractÉliashberg theory is generalized to the electronphonon (EP) systems with the not constant density of electronic states. The phonon contribution to the anomalous electron Green’s function (GF) is considered. The generalized Éliashberg equations with the variable density of electronic states are resolved for the hydrogen sulphide SHThe results of the solution of the Eliashberg equations for the Im-3m (170 GPa), Im-3m (200 GPa) and R3m (120 GPa) phases are presented. A peak value T

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46

Manos, Manolis J., and Mercouri G. Kanatzidis. "Metal sulfide ion exchangers: superior sorbents for the capture of toxic and nuclear waste-related metal ions." Chemical Science 7, no. 8 (2016): 4804–24. http://dx.doi.org/10.1039/c6sc01039c.

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47

Tan, Hui Jie, Chi Zhang, Zeng Zhang Wang, and Ping Li. "Heavy Metal Pollution of River Sludge in Taiyuan." Advanced Materials Research 243-249 (May 2011): 5280–84. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.5280.

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Samples of the sludge were collected from urban channels in Taiyuan city, and its pollution characteristics of heavy metals were researched. As the emphasis, the distribution regularity of five chemical speciation about Cd, Cr, Zn, Cu, Ni, Pb were analyzed. The results showed that the concentration of Ni, Zn, Cr over standard in various degrees. The residual metal fractions had a higher proportion for all heavy metals. Cd, Zn and Ni were predominantly associated with the carbonates bonded metal fraction and the organics-sulfide bonded metal fraction. Cu, Pb and Cr were predominantly bound to the organics/sulfide and Fe/Mn oxides, but their proportion are different. The bio-transportation index of Zn and Ni are larger than the others. This is the emphasis of heavy metal pollutions control for the local channels.

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48

Wang, Jing Yi, Jiang Xue Long, and Hong Wei Lu. "Heavy Metal Contamination of Soil in Zhuzhou Smelting." Advanced Materials Research 926-930 (May 2014): 4246–49. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.4246.

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To date, environmental issues become increasingly prominent, especially heavy metal (Pb and Zn) pollution of soil. This paper describes the procedure of detecting heavy metal content in soil from Zhuzhou Smelting in order to understand the contamination degree of heavy metals. An extensive soil survey was conducted in the plant include lead and zinc major production areas. Microwave digestion and ICP-AES technology were used to test metal content in soil. The results revealed that the soil in the area had been polluted by Pb and Zn, however, the pollution degree of each type of metals was not identical. In general, the Smelting was slightly polluted by heavy metals, with the highest concentration being in the Zinc sulfide plant. The heavy metal content in deep soil was a little bit higher than surface except for the Zinc sulfide plant. The reason may related to its particular location.

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49

Nielsen, A. H., P. Lens, T. Hvitved-Jacobsen, and J. Vollertsen. "Effects of aerobic–anaerobic transient conditions on sulfur and metal cycles in sewer biofilms." Biofilms 2, no. 2 (March 23, 2005): 81–91. http://dx.doi.org/10.1017/s1479050505001705.

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Interactions between sulfur and metals were studied in aerobic and anaerobic biofilms grown on domestic waste water at 15°C. The dominant metals in the waste water were iron, zinc and copper, which were present in average concentrations of 0.5mg/l, 0.6mg/l and 0.1m/l, respectively. Copper and zinc were found to accumulate in the anaerobic biofilm owing to precipitation of metal sulfides. Iron supplementation (approximately 5.5mg Fe/l) to the anaerobic waste water reduced the zinc and copper precipitation due to sulfide precipitation with iron. However, even at these elevated iron concentrations in the waste water, sulfide precipitation in the biofilm was controlled largely by zinc and copper. In the aerobic biofilm, addition of iron resulted in accumulation of iron and phosphate, probably owing to precipitation of iron phosphates and iron (oxy)hydroxides. The potential importance of extracellular polymeric substances (EPS) on metal sorption in sewer biofilms was studied. EPS consisted mainly of proteins (13–260mg/(g volatile solids)) and to a lesser extent of carbohydrates (8–26mg/(g volatile solids)). The EPS composition remained relatively constant during experimental runs, but differed significantly between them. No relationships between the metal content of the biofilm and the amount of extracted EPS were found, which suggests that EPS did not play a major role in the metal accumulation.

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Wu, Kaili, Baochan Yang, Xixi Zhu, Wei Chen, Xiliang Luo, Zhenxue Liu, Xiao Zhang, and Qingyun Liu. "Cobalt and nickel bimetallic sulfide nanoparticles immobilized on montmorillonite demonstrating peroxidase-like activity for H2O2 detection." New Journal of Chemistry 42, no. 23 (2018): 18749–58. http://dx.doi.org/10.1039/c8nj04647f.

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Journal articles on the topic 'Metal sulfide'

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