Fraction Of Sulfur Research Articles

Integrated Battery Scrap Recycling and Nickel Slag Cleaning with Methane Reduction

Innovative recycling routes are needed to fulfill the increasing demand for battery raw materials to ensure sufficiency in the future. The integration of battery scrap recycling and nickel slag cleaning by reduction with methane was experimentally researched for the first time in this study. Industrial nickel slag from the direct Outotec nickel flash smelting (DON) process was mixed with both synthetic and industrial battery scrap. The end products of the slag-scrap mixtures after reduction at 1400 °C in a CH4 (5 vol %)-N2 atmosphere were an Ni–Co–Cu–Fe metal alloy and FeOx–SiO2 slag. It was noted that a higher initial amount of cobalt in the feed mixture increased the recovery of cobalt to the metal alloy. Increasing the reduction time decreased the fraction of sulfur in the metal alloy and magnetite in the slag. After reduction, manganese was deported in the slag and most of the zinc volatilized. This study confirmed the possibility of replacing coke with methane as a non-fossil reductant in nickel slag cleaning on a laboratory scale, and the recovery of battery metals cobalt and nickel in the slag cleaning process with good yields.

The study of the main parameters affecting the efficiency of Claus reactor and construction of linguistic models for assessing the quality of produced sulfur

Analysis of the key technological factors of sulfur recovery process and their impact on operating efficiency of Claus reactor sulfur recovery unit at thermal and catalytic stages was carried out. The composition of acid gas entering Claus reactor and hydrogen sulfide (H2S); carbon dioxide (CO2), vapors of water, hydrocarbons, oxygen, COS and CS2, and their impact on sulfur recovery process were studied and analyzed. Dependence diagrams of the influence of selected technological factors on sulfur recovery process rates were constructed.The quality of the produced sulfur is estimated on the basis of linguistic models developed using the initial fuzzy information. Linguistic models are developed on the basis of recovery model of knowledge representation and they describe the dependence of sulfur quality indices (sulfur grade) from the mass fractions of sulfur, ash, organic substances, and water. To describe a fuzzy term ‘high quality’ of sulfur, structures of membership functions were determined.

Studies on long term effect of INM approach on forms of sulphur under rice on a Vertisol

Effect of INM approach on Sulphur farctions in rice grown on a Vertisol was studied under long-term fertilizer experiment during kharif 2019 at research farm of Indira Gandhi Krishi Vishwavidyalaya, Raipur (C.G.). The experiment comprised of different levels or doses of NPK fertilizers alone and in combination with zinc sulphate, farmyard manure (FYM), blue green algae (BGA) and green manuring (GM) was laid out in randomized block design with four replications and ten treatments viz. Control, 50% NPK,”“100% NPK,”“150% NPK,”“100% NPK”+“ZnSO4@ 10kg”ha-1,”100% NP, “100% N,”“100% NPK + FYM” @“5t ha-1”, “50% NPK+BGA”@ “10kg ha-1” and “50% NPK + GM” @“40kg ha-1. Different S fractions were estimated in surface and sub-surface soil samples before the rice transplanting (2019). Application of 150% NPK significantly increased the sulphate sulphur (36.4 kg ha-1), water soluble sulphur (35.0 kg ha-1), organic sulphur (86 kg ha-1) and heat soluble sulphur (80 kg ha-1) as compared to other treatments. A decrease in S fractions was observed with increase in the depth of soil from 0-15 to 15-30 cm. The results of surface and sub surface soil samples (0-15 cm and 15-30 cm) collected before of rice showed that zero fertilization led to decline in the levels of all the S forms, while application of sulphur containing fertilizer (SSP and ZnSO4) and organics increased it over omission of these nutrients and control. Organic sulphur was found to be the most dominant fraction (about 90%) followed by heat soluble sulphur. Integration of inorganic fertilizers with organics proved better as compared to application of inorganic fertilizers alone. Integrated use of inorganic fertilizers in conjunction with organics increased grain and straw yields over inorganically treated plots. Highest grain and straw yields of rice were recorded in 150% NPK 6970 and 8364 (kg ha-1), respectively. The yield of rice had highest correlation with sulphate sulphur (r=0.810**) followed by water soluble (r=0.793**). The values of coefficients of correlation for sulphate S, water soluble S, heat soluble S and organic S with yield of rice were 0.810**, 0.793**, 0.737** and 0.790**, respectively. All the sulphur fractions positively correlated with each other amongst continuous application of inorganic fertilizers and organic manure.

Revisiting the Role of Conductivity and Polarity of Host Materials for Long‐Life Lithium–Sulfur Battery

AbstractDespite their high theoretical energy density and low cost, lithium–sulfur batteries (LSBs) suffer from poor cycle life and low energy efficiency owing to the polysulfides shuttle and the electronic insulating nature of sulfur. Conductivity and polarity are two critical parameters for the search of optimal sulfur host materials. However, their role in immobilizing polysulfides and enhancing redox kinetics for long‐life LSBs are not fully understood. This work has conducted an evaluation on the role of polarity over conductivity by using a polar but nonconductive platelet ordered mesoporous silica (pOMS) and its replica platelet ordered mesoporous carbon (pOMC), which is conductive but nonpolar. It is found that the polar pOMS/S cathode with a sulfur mass fraction of 80 wt% demonstrates outstanding long‐term cycle stability for 2000 cycles even at a high current density of 2C. Furthermore, the pOMS/S cathode with a high sulfur loading of 6.5 mg cm−2 illustrates high areal and volumetric capacities with high capacity retention. Complementary physical and electrochemical probes clearly show that surface polarity and structure are more dominant factors for sulfur utilization efficiency and long‐life, while the conductivity can be compensated by the conductive agent involved as a required electrode material during electrode preparation. The present findings shed new light on the design principles of sulfur hosts towards long‐life and highly efficient LSBs.

Effects of Spartina alterniflora invasion on spatial and temporal variations of total sulfur and inorganic sulfur fractions in sediments of salt marsh in the Min River estuary, southeast China

Abstract To investigate the effects of Spartina alterniflora invasion on spatial and temporal variations of sulfur in marsh sediments, the levels of total sulfur (TS) and inorganic sulfur (IS) fractions (Water-Soluble-S, W-S-S; Adsorbed-S, A-S; HCl-Soluble-S, H-S-S; and HCl-Volatile-S, H-V-S) were determined in Cyperus compressus marsh (before invasion, BI), S. alterniflora-C. compressus marsh (during invasion, DI) and S. alterniflora marsh (after invasion, AI) in the Min River estuary (Southeast China) by space-for-time substitution method. Results showed that the variations of sediment texture caused by S. alterniflora invasion showed great influences on the levels of TS and IS fractions in sediments at DI and AI stages. Compared with BI stage, the mean values of TS (g·kg−1) at AI and DI stages increased by 21.36% and 20.57%, while those of TIS (mg·kg−1) increased by 24.84% and 20.59%, respectively. Over all sampling seasons, significantly higher contents of W-S-S, A-S and H-S-S in sediments at AI or DI stages were observed compared to BI stage (p

Euxinia in the Neoarchean: The starting point for early oxygenation in a Brazilian Craton

Geochemical evidence for local redox transitions is observed 300 Ma years prior to the Great Oxygenation Event (GOE ca. 2400 Ma) and suggests evolving environmental conditions through a continuous sequence where euxinia (anoxic and sulfidic) preceded the expansion of more oxidizing conditions. Based on multiproxy data such as iron speciation (FePy/FeHR > 0.7) and Mo enrichments (varying from 3 to 64), we present one of the oldest records of euxinia from the Archean Pitangui greenstone belt (~2700 Ma), Minas Gerais, Brazil. The sulfur isotopic composition of sedimentary sulfides indicates early inputs of sulfate from oxidative weathering and an attenuation of sulfur mass independent fractionation that combined with other geochemical signatures (FeHR/FeT, Ce anomalies and rare earth element fractionation) is consistent with the expansion of oxygen availability, and suggests localized oxic conditions before the GOE.

Sulfur Transformation Behavior of Inorganic Sulfur-Containing Compounds in Chemical Looping Combustion

Chemical looping combustion (CLC) is a promising technology for fuel conversion with inherent carbon capture. Because sulfur is an integral part of coal, the existence of sulfur contaminants in coal may degrade the purity of CO₂ and deteriorate the performance of the oxygen carrier in the CLC process. To uncouple the complex behavior of inorganic sulfur in coal, sulfur release of three inorganic sulfur-containing compounds (FeS₂, FeSO₄, and CaSO₄) mixed with activated carbon during the temperature-programmed process and the CLC process using iron ore as an oxygen carrier were investigated in a batch fluidized bed reactor at 950 °C. The results showed that, in the temperature-programmed process, the initial decomposition temperatures of FeS₂, FeSO₄, and CaSO₄ were about 400, 500, and 650 °C, respectively. During the reduction and oxidation stages of CLC, SO₂ was the main sulfur-containing gaseous compound. The sulfur stability of CaSO₄ was higher than those of FeS₂ and FeSO₄. The fractions of sulfur converted to gaseous species in the reduction stage (XS,g,ᵣₑd) of FeS₂ and FeSO₄ reached 90.38 and 87.42%, respectively, within 20.5 min, while the corresponding value was 53.97% for CaSO₄. During 5 cyclic redox experiments at 950 °C, the fraction of sulfur converted to gas species was almost maintained stable, while the energy-dispersive X-ray spectroscopy analysis showed the accumulation of sulfur after the cyclic reaction.

Research on the quality of diesel fuel provided by LLC Ferronordic Trading House

Ferronordic is the official dealer for Volvo Construction Equipment, Dressta, Mecalac and Rottne. In addition to sales and after-sales support for Volvo Construction Equipment, the company is a dealer for servicing Volvo and Renault Trucks, as well as a dealer for Volvo Penta for servicing industrial and marine engines in some regions of Russia. The company collaborates with other well-known brands and several suppliers of attachments. The Swedish concern Volvo Group supplies to the Russian market trucks equipped with diesel engines with Common Rail injection system, as well as with pump nozzles. Diesel mechanical and electronic pump nozzles perform timely and metered injection of the working mixture into the combustion chambers of the cylinders of a diesel engine. The mechanical nozzles are driven by a high-pressure fuel pump, while the electronic ones are controlled by the Common Rail electronic injection system and are constantly under intense mechanical stress. Poor quality diesel fuel leads to: loss of power, lack of traction and instability of the engine; overexpenditure and fuel leakage from sprayers; change in spray angle and time; change in the amount of injected mixture; the appearance of knocks and noises, black and bluish smoke during exhaust. The results of research work on the study of the quality of diesel fuel of the company LLC Ferronordic Trading House are presented. The physicochemical properties of diesel fuel were studied experimentally, such as: density, fractional composition, mass fraction of sulfur, mass fraction of water, flash point, limiting filterability temperature and cloud point.

Air pollution and particulate matter composition in relation to epigenetic age

OPS 48: Air pollution and epigenetics, Room 417, Floor 4, August 26, 2019, 4:30 PM - 5:30 PM Background. Air pollution is associated with numerous adverse health outcomes. Advanced epigenetic age, estimated using DNA methylation, may be a marker of biological consequences of prolonged air pollution exposure. Methods. In a sample of non-Hispanic white women ages 35-74 living in the contiguous U.S. (n=2,764), we estimated annual average ambient residential levels of PM2.5, PM10 and NO2 using a model combining land-use regression and kriging fit to regulatory monitoring data. Predictive k-means was used to assign participants to one of 7 clusters that corresponded to different relative combinations of PM2.5 components. We measured DNA methylation (DNAm) in blood samples using the Illumina’s Infinium HumanMethylation450 BeadChip and calculated DNAm age using the Levine/PhenoAge clock. Age acceleration was derived by regressing DNAm age on chronological age and calculating the residuals. Using linear regression models accounting for blood cell composition, we estimated adjusted associations between an interquartile range (IQR) increase in pollutants and age acceleration. We stratified the associations for PM2.5 by component cluster membership. Results. Higher age acceleration was observed for PM10 (β=0.24, 95% CI: 0.03, 0.46) but not for NO2. For PM2.5, we observed heterogeneity by component cluster membership (p for interaction=0.001). PM2.5 was associated with an almost 4-year higher age acceleration in a cluster characterized by higher relative fractions of crustal elements Si, Ca, K and Al (β=3.96, 95% CI: 0.72, 7.20), and an almost 2-year higher age acceleration in a cluster characterized by low sulfur fractions relative to overall PM2.5 (β=1.94, 95% CI: 0.41, 3.46). In contrast, PM2.5 was inversely associated with age acceleration in a cluster distinguished by low relative nitrite concentrations (β=-1.84, 95% CI: -3.19, -0.48). Conclusions. Air pollution was associated with epigenetic age, a marker of mortality and disease risk, with heterogeneity in the association between PM2.5 and epigenetic age acceleration by particulate matter composition.

Can organic haze and O2 plumes explain patterns of sulfur mass-independent fractionation during the Archean?

The existence of mass-independently fractionated sulfur in Archean rocks is almost universally accepted as evidence for low atmospheric O2 and O3 concentrations at that time. But the detailed patterns of the Δ33S values and of the ratios Δ33S/δ34S and Δ36S/Δ33S remain to be explained, and the mechanism for producing the mass-independent fractionation remains controversial. Here, we explore the hypothesis that the relatively low Δ33S values seen during the Mid-Archean, 2.7-3.5 Ga, were caused by the presence of organic haze produced from photolysis of methane. This haze helped shield SO2 from photolysis, while at the same time providing surfaces on which unfractionated short-chain sulfur species could condense. The evolution of oxygenic photosynthesis, and the concomitant disappearance of organic haze towards the end of the Archean allowed more negatively fractionated S4 and S8 to form, thereby generating large positive fractionations in other sulfur species, including sulfate and H2S. Reduction of this sulfate to H2S by bacteria, followed by incorporation of H2S into pyrite, produced the large positive Δ33S values observed in the Neoarchean rock record, 2.5-2.7 Ga.

Characterization of organosulfur compounds in asphalt cement samples by ESI(+)FT-ICR MS and 13C NMR spectroscopy

Herein, it is presented a methodology for the characterization of organosulfur compounds in asphalt cement (AC) samples employing solid-phase extraction (SPE) associated with methylation reactions and positive-ion mode electrospray Fourier transform ion cyclotron resonance mass spectrometry (ESI(+)FT-ICR MS) and carbon-13 nuclear magnetic resonance (13C NMR) spectroscopy. Three AC samples were submitted to an SPE separation, and the fractions obtained the original AC samples, and their maltenes were methylated and analyzed using the ESI(+)FT-ICR MS. The ESI(+)FT-ICR MS ionized the sulfur fractions much better than the original samples, detecting organosulfur compounds with a broader average molecular mass distribution (Mw). Several types of sulfur compounds were detected, such as sulfides, disulfides, thiophenes, and dibenzothiophenes. Besides, the ESI(+)FT-ICR data were compared with the 13C NMR (from model molecules analyses) and ESI(+)-Orbitrap MS. The organosulfur chemical profile was correlated to the physical properties of AC samples. It was verified that the samples with higher aromatic-character were less susceptible to aging test, while the one with more saturated-character presented more significant variation in their physical properties after the aging test.

Air pollution, particulate matter composition and methylation-based biologic age

BackgroundEpigenetic age, as defined by DNA methylation, may be influenced by air pollution exposure. ObjectiveTo evaluate the relationship between NO2, particulate matter (PM), PM components and accelerated epigenetic age. MethodsIn a sample of non-Hispanic white women living in the contiguous U.S. (n = 2747), we estimated residential exposure to PM2.5, PM10 and NO2 using a model incorporating land-use regression and kriging. Predictive k-means was used to assign participants to clusters representing different PM2.5 component profiles. We measured DNA methylation (DNAm) in blood using the Illumina's Infinium HumanMethylation450 BeadChip and calculated DNAm age using the Hannum, Horvath and Levine epigenetic clocks. Age acceleration was defined based on residuals after regressing DNAm age on chronological age. We estimated associations between interquartile range (IQR) increases in pollutants and age acceleration using linear regression. For PM2.5, we stratified by cluster membership. We examined epigenome-wide associations using robust linear regression models corrected with false discovery rate q-values. ResultsNO2 was inversely associated with age acceleration using the Hannum clock (β = −0.24, 95% CI: −0.47, −0.02). No associations were observed for PM10. For PM2.5, the association with age acceleration varied by PM2.5 component cluster. For example, with the Levine clock, an IQR increase in PM2.5 was associated with an over 6-year age acceleration in a cluster that has relatively high fractions of crustal elements relative to overall PM2.5 (β = 6.57, 95% CI: 2.68, 10.47), and an almost 2-year acceleration in a cluster characterized by relatively low sulfur fractions (β = 1.88, 95% CI: 0.51, 3.25). In a cluster distinguished by lower relative nitrate concentrations, PM2.5 was inversely associated with age acceleration (β = −1.33, 95% CI: −2.43, −0.23). Across the epigenome, NO2 was associated with methylation at 2 CpG sites. ConclusionAir pollution was associated with epigenetic age, a marker of mortality and disease risk, among certain PM2.5 component profiles.

Frequency and intensity of nitrogen addition alter soil inorganic sulfur fractions, but the effects vary with mowing management in a temperate steppe

Abstract. Sulfur (S) availability plays a vital role in driving functions of terrestrial ecosystems, which can be largely affected by soil inorganic S fractions and pool size. Enhanced nitrogen (N) input can significantly affect soil S availability, but it still remains largely unknown if the N effect varies with frequency of N addition and mowing management in grasslands. To investigate changes in the soil S pool and inorganic S fractions (soluble S, adsorbed S, available S, and insoluble S), we conducted a field experiment with different frequencies (two times per year vs. monthly additions per year) and intensities (i.e., 0, 1, 2, 3, 5, 10, 15, 20, and 50 g N m−2 yr−1) of NH4NO3 addition and mowing (unmown vs. mown) over 6 years in a temperate grassland of northern China. Generally, N addition frequency, N intensity, and mowing significantly interacted with each other to affect most of the inorganic S fractions. Specifically, a significant increase in soluble S was only found at high N frequency with the increasing intensity of N addition. Increasing N addition intensity enhanced adsorbed S and available S concentrations at low N frequency in unmown plots; however, both fractions were significantly increased with N intensity at both N frequencies in mown plots. The high frequency of N addition increased the concentrations of adsorbed S and available S in comparison to the low frequency of N addition only in mown plots. Changes in soil S fractions were mainly related to soil pH, N availability, soil organic carbon (SOC), and plant S uptake. Our results suggested that N input could temporarily replenish soil-available S by promoting dissolution of soil-insoluble S with decreasing soil pH and mineralization of organic S due to increasing plant S uptake. However, the significant decrease in organic S and total S concentrations with N addition intensity in mown plots indicated that N addition together with biomass removal would eventually cause soil S depletion in this temperate grassland in the long term. Our results further indicated that using large and infrequent N additions to simulate N deposition can overestimate the main effects of N deposition and mowing management on soil S availability in semiarid grasslands.

Diversity decoupled from sulfur isotope fractionation in a sulfate-reducing microbial community.

The extent of fractionation of sulfur isotopes by sulfate-reducing microbes is dictated by genomic and environmental factors. A greater understanding of species-specific fractionations may better inform interpretation of sulfur isotopes preserved in the rock record. To examine whether gene diversity influences net isotopic fractionation in situ, we assessed environmental chemistry, sulfate reduction rates, diversity of putative sulfur-metabolizing organisms by 16S rRNA and dissimilatory sulfite reductase (dsrB) gene amplicon sequencing, and net fractionation of sulfur isotopes along a sediment transect of a hypersaline Arctic spring. In situ sulfate reduction rates yielded minimum cell-specific sulfate reduction rates<0.3×10-15 moles cell-1 day-1 . Neither 16S rRNA nor dsrB diversity indices correlated with relatively constant (38‰-45‰) net isotope fractionation (ε34 Ssulfide-sulfate ). Measured ε34 S values could be reproduced in a mechanistic fractionation model if 1%-2% of the microbial community (10%-60% of Deltaproteobacteria) were engaged in sulfate respiration, indicating heterogeneous respiratory activity within sulfate-reducing populations. This model indicated enzymatic kinetic diversity of Apr was more likely to correlate with sulfur fractionation than DsrB. We propose that, above a threshold Shannon diversity value of 0.8 for dsrB, the influence of the specific composition of the microbial community responsible for generating an isotope signal is overprinted by the control exerted by environmental variables on microbial physiology.

Effect mass independent isotope fractionation of sulfur (δ33S and δ36S) during photolysis SO2 in experiments with broadband light source

This paper presents the results of experimental studies to examine the behavior of mass-independent isotope effects of sulfur Δ33S and Δ36S during photochemical processes initiated by broadband ultraviolet radiation. Experiments were performed in a flow photochemical reactor using a high pressure mercury lamp which is a source of radiation of a wide range with a maximum radiation intensity in the wavelength range 270-330 nm and weaker in the range 190-250 nm. We present measurements of the temperature and SO2 pressure dependence of the sulfur isotope ratios in the elemental sulfur products. Based on a comparative analysis of our isotope data with data from previous experimental studies with xenon and hydrogen lamps, it was shown that the character of the correlation dependences between the values of δ34S, Δ33S and Δ36S in elemental sulfur depends on the relative spectral distribution of the radiation intensity. Based on a comparison of our isotope data with data from previous experimental studies with xenon and hydrogen lamps, it was shown that the character of the correlation dependencies between the values of δ34S, Δ33S and Δ36S in elemental sulfur depends on the relative spectral distribution of the radiation intensity. The results of our experiments allow the possibility that photochemical processes in the range 250-330 nm could play a significant role in the production of an isotope sulfur anomaly in the Archean atmosphere. The conditions in which radiation in the 250-330 nm region prevail over the radiation in the 190-220 nm region are consistent with the assumption that the level of solar radiation reaching the Earth’s surface in Archean was several orders of magnitude larger in the wavelength range 200-300 nm compared with the current level of radiation in this range.

Effect of Mass-Independent Isotope Fractionation of Sulfur (Δ33S and Δ36S) during SO2 Photolysis in Experiments with a Broadband Light Source

Abstract–This paper presents the results of experimental studies of the behavior of mass-independent isotope effects of sulfur Δ33S and Δ36S during photochemical processes initiated by a broadband ultraviolet radiation. Experiments were performed in a flow photochemical reactor using a high-pressure mercury lamp, which is a source of radiation of a wide range with maximum radiation intensity in the wavelength range of 270−330 nm and weaker intensity in the range of 190−250 nm. The temperature and SO2 pressure dependences of the sulfur isotope ratios in the elemental sulfur products are revealed. Based on a comparative analysis of our isotope data with data from previous experimental studies with xenon and hydrogen lamps, it was shown that the correlation between the values of δ34S, Δ33S and Δ36S in elemental sulfur depends on the relative spectral distribution of the radiation intensity. Based on a comparison of our isotope data with data from previous experimental studies with xenon and hydrogen lamps, it was shown that the correlation between the values of δ34S, Δ33S and Δ36S in elemental sulfur depends on the relative spectral distribution of the radiation intensity. Our experiments suggest that photochemical processes in the range of 250−330 nm could play a significant role in the production of an isotope sulfur anomaly in the Archean atmosphere. The conditions in which 250− 330 nm radiation prevails over the 190−220 nm radiation are consistent with the assumption that the level of solar radiation reaching the Earth’s surface in Archean was several orders of magnitude higher in the wavelength range 200−300 nm compared with the current level of radiation in this range.

Stable Isotope (S, Mg, B) Constraints on the Origin of the Early Precambrian Zhaoanzhuang Serpentine-Magnetite Deposit, Southern North China Craton

The origin of the Zhaoanzhuang serpentine-magnetite deposit in the southern North China Craton (NCC) is highly disputed, with some investigators having proposed an ultramafic origin, whereas others favor a chemical sedimentary origin. These discrepancies are largely due to the difficulty in determining the protolithic characteristics of the highly metamorphosed rocks. Sulfur, magnesium, and boron isotope geochemistry combined with detailed petrography was carried out in this study to constrain the original composition of the Zhaoanzhuang iron orebodies. Anhydrite is present as coarse crystals intergrown with magnetite, indicating that the anhydrite formed simultaneously with the magnetite during metamorphism rather than as a product of later hydrothermal alteration. The anhydrite has a narrow range of positive δ34S values from +19.8 to +22.5‰ with a mean value of +21.1‰. These values are significantly higher than that of typical magmatic sulfur (δ34S = 0 ± 5‰) and deviate away from primary igneous anhydrite towards mantle-sulfur isotopic values, but they are similar to those of marine evaporitic anhydrite and gypsum (~+21‰). The sulfur isotopic compositions of several samples show obvious signs of mass-independent sulfur fractionation (Δ33S = −0.47‰ to +0.90‰), suggesting that they were influenced by an external sulfur source through a photochemical reaction at low oxygen concentrations, which is consistent with the Neoarchean-Paleoproterozoic atmosphere. Coarse-grained tourmaline from the tourmaline-rich interlayers of the orebodies occurs closely with Mg-rich minerals such as phlogopite, talc, and diopside, indicating that it has a metamorphic origin. The δ11B values of the tourmaline range from −0.2‰ to +3.6‰ with a mean value of +2.0‰, which is much positive relative to that of magmatic tourmaline but is consistent with that of carbonate-derived tourmaline. The magnesium isotopic analyses of the serpentine–magnetite ores and the magnesium-rich wall rocks revealed a wide range of very negative δ26Mg values from −1.20‰ to −0.34‰ with an average value of −0.80‰. The value is higher than that of ultramafic rocks (δ26Mg = −0.25‰) and exhibits minor Mg isotopic fractionation. However, these values are consistent with those of marine carbonate rocks, which have lower δ26Mg values and larger Mg isotopic variations (δ26Mg = −0.45‰ to −4.5‰). Collectively, the S–Mg–B isotopic characteristics of the Zhaoanzhuang iron orebodies clearly indicate a chemical sedimentary origin. The protoliths of these orebodies most likely reflect a series of Fe–Si–Mg-rich marine carbonate rocks with a considerable evaporite component, indicating a carbonate-rich superior-type banded iron formation precipitated in an evaporitic shallow marine sedimentary environment.

THE IMPROVEMENT OF THE TECHNOLOGICAL SCHEME OF PRODUCTION OF STABILIZED AND PROCESSED CATALYST OF THE MEDIUM-TEMPERATURE CONVERSION OF OXIDE CARBON

The article deals with the possibility of reducing the environmental burden on the environment, for example, by introducing changes in the technological scheme for the production of a stabilized and reformed catalyst for the average temperature conversion of carbon monoxide by steam (STC) from the waste of titanium (IV) oxide production with a low mass fraction of sulfur. The rational conditions of processes of sedimentation, aging, washing and thermal decomposition are proposed, and it allows to reduce the cost price of the target product by eliminating from the technological process the desulfurization stage. The possibility of stabilizing the STK catalyst with hydroxide has been proved. It was determined that the use of samples with ω [Ca (OH) 2] ~ 0.75 mass. % completely eliminates the stage of their desulphurization, since the maximum concentration of H2S in the gas phase at the exit from the reactor was meager at an industrial scale of 0.04 mg / m3. The activity of the obtained samples of the catalyst STK for the constant of the rate of reaction of CO conversion with water vapor at 350 ° C, which averages 2.15 cm3 / (g ∙ s), corresponds to the current level of activity of existing catalysts STK. It has been established that the use of co-precipitation of all catalyst components differs favorably from the prevailing separation deposition. And with the addition of a flocculant based on [(-CH2CHCONH2-) n] polyacrylamide and a high molecular weight polyethylene oxide [(-OSH2CH2-) n], in comparison with the simple process of settling, the sedimentation rate increases 3 ÷ 6 times depending on the concentration of the flocculant. This solution allows to obtain a catalyst with increased activity and thermal stability. In this case, the use of chromium (III) sulphate instead of chrome (VI) oxide can facilitate and improve the efficiency of co-precipitation of catalyst components STK. It was established that the introduction of changes in the technological scheme of production, contributes to reducing energy costs and improving the state of environmental safety.

Electrochemical and Optical Properties of Lithium Ion Conducting LiPSON Solid Electrolyte Films

Lithium phosphorous sulfuric oxynitrides (LiPSON) with different compositions have been prepared by rf‐sputtering using sputter targets with various mixtures of Li3PO4 and Li2SO4. Morphology, composition, and electrochromic properties of the fabricated thin films were investigated using solid state analysis methods like scanning electron microscopy (SEM), X‐ray photoelectron spectroscopy (XPS), optical transmission spectroscopy, and electrochemical impedance spectroscopy. The composition of the thin films changes due to the varying fractions of process gases. The highest fraction of sulfur is about 1.3 at% validated using XPS. The optical bandgap shifts in the range of 3.7 eV up to 5.3 eV for the different fractions of process gases. Transmission in the UV range is above 60% for most of the sputtered solid electrolyte thin films whereas in the visible range of the electromagnetic spectrum a transmission above 80% is observed. The highest ionic conductivity is identified for the thin films with 4 sccm nitrogen and no additional argon as process gas. However, ionic conductivity is expected to increase with increasing sulfur content and with change of the ratio between different nitrogen coordinations.

Effect of processing at the steel vacuum processing unit (SVPU) on desulfurization of unmodified and modified KP-2 steel

The object of the research is the processes of statistical processing of the chemical composition of KP-2 wheel steel. One of the most problematic places in the smelting of modern steel is the stability of the chemical composition due to the use of uncontrolled content of scrap, charge and standard modifiers, which are made by the fused method. To eliminate this problem, multifunctional modifiers were used during the study. This is due to the fact that the KP-2 steel modification method proposed in this article has a number of features. In this case, the influence modifiers of multifunctional action on the installation of vacuum processing of steel on desulfurization of wheel steel KP-2, obtained under the conditions of the open joint-stock company «Interpipe NTRP» (Dnipro, Ukraine), is established. In particular, when treating a steel melt with multifunctional modifiers, not only a refining effect occurs, but also an increase in the stability of the chemical composition and level of mechanical characteristics of the KP-2 wheeled steel. This is confirmed by the coefficients of variation and interfusion difference presented in the article (span), obtained by statistical processing of a large data set – 442 serial heats and 1 modified (6 wheels). Thanks to the multifunctional modification, the level of mechanical characteristics and the quality of the finished wheels really increases. Compared with similar mass-produced materials, such as FeSi, FeCa, FeMn, SiCa, the use of new multifunctional modifiers in KP-2 wheel steel provides a significant reduction in the mass fraction of sulfur than in the same metal that is processed in the traditional way. It is established that the use of multifunctional modifiers changes the shape of non-metallic inclusions to globular and reduces their number, which also increases the level of mechanical properties of KP-2 wheel steel. The obtained coefficients of variation prove that the mechanical characteristics of KP-2 modified steel are more stable than in serial melts of the same steel. This will increase the demand and quality of these railway wheels.