Total Sulfur Levels Research Articles

Sulfur dynamics in saline sodic soils: The role of paddy cultivation and organic amendments

The phenomenon of sulfur (S) deficiency in Chinese soil is becoming increasingly severe, especially in the northeastern saline-sodic wasteland (WL). To determine the bioavailability of S in long-term cultivated paddy soil with or without organic amendment addition, the long-term field experiment site was established and incubation experiments were conducted. Compared to WL, soil properties have been continuously improved during the 15-year paddy field (PF) cultivation, ultimately enhancing the content of soil organic carbon (by 242.62 %), total nitrogen (by 126.49 %) and alkali-hydrolyzed nitrogen (by 28.07 %). Additionally, soil salinization has been decreasing, and the stock of total sulfur (TS) and available sulfur (AS) in the 0–60 cm soil layer have increased by 32.09 % and 293.52 % respectively. In contrast, organically-amended soil (OA) manifested superior TS and AS levels vs. PF. Additionally, water-soluble sulfur (WSS) was markedly elevated, registering post-annual increments of 227.31 % and 268.36 % in PF and OA, respectively, relative to WL. The key mechanistic impetus for the application of organic amendments was the enhancement of the soil's adsorptive and mineralization capabilities. As observed in our soil culture experiment, the maximum adsorption of sulfate ions and the cumulative mineralization of sulfur in the soil follow the pattern of OA > PF > WL. The Partial Least Squares Path Model (PLSPM) corroborated that both organic amendments and years of cultivation indirectly influenced total inorganic sulfur fractions. This influence is primarily mediated via structural soil enhancements and salinization amelioration, thereby elevating available quantities of sulfur in saline-sodic soil environments. In conclusion, from the perspective of soil sulfur biogeochemical cycling, we have confirmed that reclaiming saline-sodic wasteland for paddy field could be a beneficial and sustainable approach for soil management. These findings of this study can also provide an in-depth understanding of the bioavailability and influencing mechanism of sulfur in long-term saline-sodic paddy fields.

Diversity and succession of chemolithoautotrophic microbial community along a recently deglaciation chronosequence on the Tibetan Plateau.

Glaciers in high-altitude mountain regions are retreating rapidly due to global warming, exposing deglaciated soils to extreme environmental conditions, and microbial colonization. However, knowledge about chemolithoautotrophic microbes, which play important roles in the development of oligotrophic deglaciated soils prior to plant colonization, remains elusive in deglaciated soils. Using real-time quantitative PCR and clone library methods, the diversity and succession of the chemolithoautotrophic microbial community harboring the cbbM gene across a 14-year deglaciation chronosequence on the Tibetan Plateau were determined. The abundance of the cbbM gene remained stable for the first 8 years after deglaciation and then increased significantly, ranging from 105 to 107 gene copies g-1 soil (P < 0.001). Soil total carbon increased gradually to 5-year deglaciation and then decreased. While total nitrogen and total sulfur levels were low throughout the chronosequence. Chemolithoautotrophs were related to Gammaproteobacteria and Betaproteobacteria, with the former dominating early deglaciated soils and the latter dominating older deglaciated soils. The diversity of chemolithoautotrophs was high in mid-age deglaciated soils (6-year-old) and was low in early (3-year-old) and older deglaciated soils (12-year-old). Our findings revealed that chemolithoautotrophic microbes colonize deglaciated soils quickly and follow a clear successional pattern across recently deglaciated chronosequences.

Response of bacterial diversity and community structure to metals in mangrove sediments from South China

Human activities have given rise to metal contamination in the constituents of mangrove ecosystems, posing a critical threat to sediment microorganisms; hence, it is of great importance to comprehend the effects of metals on the microbial communities in mangrove sediments. This study was the first to explore the response of the bacterial diversity and community structure to nine metals (As, Co, Cr, Cu, Mn, Ni, Pb, V and Zn) and organic matter fractions (including total organic carbon (TOC), total nitrogen (TN), and total sulfur (TS)) in mangrove wetlands from Zhanjiang, China, using 16S rRNA high-throughput sequencing technology and Spearman correlation analysis. The results showed that these nine metals were scattered differently in different mangrove sediments, and the metals and organic matter fractions jointly affected the bacterial communities in the sediments. Several metals displayed significant positive correlations with the abundances of the phylum Bacteroidetes and the genera Actibacter and Sphingobacterium but significant negative correlations with the abundances of two genera Holophaga and Caldithrix. Furthermore, the abundances of the phylum Actinobacteria and many bacterial genera showed significant positive or negative responses to the levels of the three organic matter fractions. Interestingly, the levels of a number of bacterial genera that exhibited increased abundance with high levels of metals and TS might be reduced with high TOC and TN, and vice versa: the levels of genera that exhibited decreased abundance with high levels of metals and TS might be increased with high TOC and TN. Overall, many bacterial groups showed different response patterns to each metal or organic matter fraction, and these metals together with organic matter fractions influenced the bacterial diversity and community structure in mangrove sediments.

Spatial and Temporal Variations of Sulfur in Plant-Soil Systems of Phragmites australis and Cyperus malaccensis Marshes in a Typical Subtropical Estuary (Min River), China

To investigate the spatial and temporal variations of sulfur (S) in plant-soil systems of Phragmites australis (PA, native invasive species) and Cyperus malaccensis (CM, common native species) marshes, in situ filed sampling was conducted in the two marshes at different seasons. Results showed that the variations of total sulfur (TS) contents in soils differed among seasons or marshes. Higher levels of TS in soils of PA marsh generally occurred in winter and summer, while those of CM marsh were observed in spring and autumn. Except for winter, the levels of TS in topsoil of CM marsh in other seasons were much higher than those of PA marsh. The variations of TS contents in soils of PA and CM marshes were dependent on the differences in physical and chemical properties (particularly electrical conductivity) of the two marshes and the differences in S absorption and utilization of the two plants. The levels of TS and the accumulation factors of S (AFS) in PA or CM differed within seasons or tissues, which could be interpreted by the differences in growth rhythm and ecological traits between the two plants. The roots/stems (R/S) and roots/leaves (R/L) ratios in PA or CM were mostly than 1, while the stems/leaves (S/L) ratios in both plants were less than 1. Allocations of S in roots of PA were generally higher than those of CM, while the values in aboveground parts of PA were much lower than those of CM. This paper found that the two plants might adopt different strategies for S accumulation and allocation to maintain their competitiveness. The PA might compete primarily by increasing the S accumulation capacities of its roots, whereas the CM might resist the spatial expansion of PA by enhancing the S accumulation capacities of its aboveground tissues.

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

Identifikasi Batuan PAF, NAF dan UNCERTAIN dengan Menggunakan Metode NTAPP Pada Area PT. Trubaindo Coal Mining, Melak-Kalimantan Timur

The research about identification of PAF, NAF and uncertain rock using NTAPP method in the PT. Trubaindo Coal Mining has been done. This research was conducted as an effort to control the potential for the formation of acid mine drainage, with identifying the types of mine rocks using certain testing methods. Some important parameters such as Total Sulfur Level, Slurry pH, Total Actual Acidity (TAA), Chromium Reducible Sulfur (CRS) and Acid Neutralizing Capacity (ANC) using the NTAPP method on mine rocks have been determined to identify mining rock category categories. Based on the results of tests on 101 samples, 63 samples were identified included in the category of rocks that are not NAF (Slurry pH value = 4.1 - 8.9; Total Sulfur = 0.01-0.60 %; CRS = 0.01-0.10 % and NTAPP = 0.030-0.959 %), 38 samples were classified as PAF (pH Slurry = 2.9-7.9; Total Sulfur = 0.01-5.10 %; CRS = 0.11-2.04 % and NTAPP = 0.053-4.571 %), and no sample was included in the uncertainty category.

Spatial and seasonal distribution of carbon, nitrogen, phosphorus, and sulfur and their ecological stoichiometry in wetland soils along a water and salt gradient in the Yellow River Delta, China

Top soils (0–10 cm) were collected in three sampling belts during four seasons in 2014, including bare land (HN1), Calamagrostis epigeios (HN2), Typha orientalis (HN3), Phragmites australis (HN4), Tamarix chinensis (HN5) and Suaeda salsa (HN6) along a water and salinity gradient in the Yellow River Delta, China. Soil organic carbon (SOC), total nitrogen (TN), total phosphorous (TP), total sulfur (TS) and their ecological stoichiometry were measured to investigate their seasonal and horizontal distribution patterns, as well as their important influencing factors such as electric conductivity (EC) and water content (WC). Our results showed that the contents of SOC and TN exhibited similar changing tendency along the water and salinity gradient. The TP contents followed the order HN5 ≈ HN2 > HN3 ≈ HN6 > HN4 > HN1. TS levels generally increased with increasing salinity from HN1 to HN6. The higher levels of SOC and TP were mostly observed in October and August, respectively, while the seasonal variations in TN were heterogeneous under different plant covers. TS contents were lower in August compared with other sampling periods except for HN4. The mean values of the C/N, C/P and C/S ratios along a water-salinity gradient ranged from 26 to 72, 20 to 74, and 61 to 292, respectively. Generally, higher C/P ratios were observed in sampling sites with plant covers in October expect for HN1, whereas they were lower in January or August. SOC, TN and TP were significantly positively correlated with soil organic matter (SOM), silt, WC and cation exchange capacity (CEC) (p < 0.05), whereas TS showed a positive correlation with EC and cations content (p > 0.05). Bulk density (BD) had a great influence on C/N ratio, C/P ratio were mainly effected by SOM, EC and silt, while C/S ratio showed a significant negative correlation with BD, EC, K+, Na+, and Mg2+ (p < 0.05).

Flow injection gas chromatography with sulfur chemiluminescence detection for the analysis of total sulfur in complex hydrocarbon matrixes.

A fast and reliable analytical technique for the determination of total sulfur levels in complex hydrocarbon matrices is introduced. The method employed flow injection technique using a gas chromatograph as a sample introduction device and a gas phase dual-plasma sulfur chemiluminescence detector for sulfur quantification. Using the technique described, total sulfur measurement in challenging hydrocarbon matrices can be achieved in less than 10s with sample-to-sample time <2min. The high degree of selectivity and sensitivity toward sulfur compounds of the detector offers the ability to measure low sulfur levels with a detection limit in the range of 20ppb w/w S. The equimolar response characteristic of the detector allows the quantitation of unknown sulfur compounds and simplifies the calibration process. Response is linear over a concentration range of five orders of magnitude, with a high degree of repeatability. The detector's lack of response to hydrocarbons enables direct analysis without the need for time-consuming sample preparation and chromatographic separation processes. This flow injection-based sulfur chemiluminescence detection technique is ideal for fast analysis or trace sulfur analysis.

Soil Nutrient Assessment and Characterization in a Degraded Central Florida Swamp

Flatford Swamp, a 2800-acre forested wetland in east Manatee County, Florida, serves as the headwaters of the Myakka River. Over the last two decades, Flatford swamp has experienced significant tree mortality. The cause of this mortality, as well as dramatic encroachment of several invasive herbaceous and shrub species, is thought to be linked to hydrologic alterations that resulted in increased inundation during the wet and dry seasons. A biogeochemical characterization of wetland soils was conducted to (1) establish a baseline spatial distribution of soil P and N in Flatford Swamp, (2) determine if soil biogeochemistry could be related to tree mortality, and (3) determine if soil biogeochemical conditions may affect future restoration efforts. Mean total nitrogen and total carbon in sampled soils ranged from 13.8 to 24.9 mg kg−1 and 211 to 468 mg kg−1, respectively, indicating that soils are predominantly organic. Environmental conditions suggest that the nitrate-reduction process occurs readily in Flatford Swamp, and thus N abatement will continue naturally during restoration. Soil total phosphorus content is significantly higher than expected and is likely one of several contributing factors that led to observed changes in vegetation community structure. Levels of total sulfur, total calcium, and conductivity, indicative of agricultural use of groundwater for irrigation, suggest sulfide toxicity as a plausible contributing mechanism in the observed dieback of Nyssa sylvatica var. biflora.

Effects of Water Level and Salinity on Total Sulfur Contents in Salt Marsh Soils of the Yellow River Delta, China

A field experiment was conducted on three different water levels and four salinity levels to investigate the effects of water level and salinity on the total sulfur (TS) content of marsh soil in the Yellow River Delta of China. The total sulfur content of surface and subsurface soils from incubated soil cores were measured under different water and salinity levels on three sampling dates. Our results showed that a higher TS content appeared in surface soils under a 5 cm water level on different sampling dates, of which higher TS content was observed in August (916 mg/kg) and October (1,335 mg/kg) under a 16.7‰ salinity level. However, a higher TS level (1,167 mg/kg) was observed under a 0.52‰ salinity level in September. Meanwhile, a lower TS content appeared in subsurface soils under a 10 cm water level at a 10.2‰ salinity level. The interaction of the water level and salinity had a significant effect on both the TS content and the C/S ratio. The TS content was significantly correlated with soil organic matter. However, a significant correlation between the total sulfur and the C/N ratio was not observed.

Total Sulfur Levels in Refined Petroleum Products of Southwestern Nigeria Using UV/VIS Spectrophotometer

This study employed turbidimetric method using a UV/VIS spectrophotometer to determine the total sulfur levels of refined petroleum products in Southwestern Nigeria. The sulfur concentrations in the analyzed fuel samples were 0.0019–0.0178 wt% and 0.027–0.169 wt% for gasoline and diesel, respectively. Sulfur levels in the selected samples were below the Nigerian standard for gasoline and diesel while 89.9% of the samples exceeded the U.S. Environmental Protection Agency standard. The turbidimetric method showed better performance than the gravimetric method. The results gave insight into the adverse environmental impact the nonuniform quality of fuels imported could pose to the country.

Catalytic Oxidative Desulfurization of Gasoline Using Ionic Liquid Emulsion System

With the aim of deep desulfurization of the gasoline, an amphiphilic catalyst, which is composed of lacunary anion [PW11O39]7- and quaternary ammonium cation [C18H37(CH3)3]N+, assembled in hydrophobic ionic liquid emulsions, can oxidize the sulfur compounds present in oil into their corresponding sulfones under ambient reaction conditions. In this process, catalytic oxidation of sulfur-containing molecules in model oil was investigated in detail under different reaction conditions (including different desulfurization systems, H2O2/DBT molar ratio, temperature, and various sulfur compounds). Moreover; this ionic liquid emulsion system could be recycled five times with an unnoticeable decrease in catalytic activity, and, from the kinetics study, it can be shown that the catalytic oxidative reaction is a pseudofirst-order reaction and the half-life is 30.4 min. Furthermore, the mechanism of catalytic oxidation desulfurization was elaborated, and the total sulfur level of real gasoline can be decreased from 1...

Sulfur Tolerant Anodes for Solid Oxide Fuel Cells

Conventional solid oxide fuel cells (SOFC) utilize nickel / yttria-stabilized zirconia cermet anodes that are rapidly poisoned by sulfur. Hydrogen sulfide content in the reformate of 2 ppmv (at 1000{degree sign}C) is known to poison the anode. Military fuels, such as JP-8 and JP-5, contain total sulfur levels that far exceed the levels that can damage the typical anode. Typical sulfur levels for these fuels would be 500-600 ppmv for the reformate from a steam reformer and 300-400 ppmv from a partial oxidation reformer. Though most systems utilize a desulfurization step, occasional sulfur slip must be anticipated. Research at Ceramatec, Inc has developed an approach to increasing sulfur tolerance through a combination of material selection and modification.

Biodesulfurization of DBT in tetradecane and crude oil by a facultative thermophilic bacterium Mycobacterium goodii X7B

Mycobacterium goodii X7B, a facultative thermophilic bacterium, cleaving the C-S bond of dibenzothiophene via a sulfur-specific pathway, was investigated for DBT in tetradecane and crude oil desulfurization. The extent of growth was improved by fed-batch culture controlled at a constant pH. The total sulfur level of dibenzothiophene in tetradecane, was reduced by 99%, from 200 to 2 ppm within 24h at 40 degrees C. After 72 h treatment, 59% of the total sulfur content in Liaoning crude oil was removed, from 3600 to 1478 ppm.

Contrast activities of four alumina and alumina–silica-supported nickel–molybdenum sulfide catalysts for deep desulfurization of gas oils

Four NiMoS catalysts on conventional alumina (NMA-1), acidified alumina (NMA-2), and on two alumina–silica mixtures of different preparation procedures with 70% (NMASA1-70) and 50% (NMASA2-50) silica supports were prepared. In HDS and HDN of straight run gas oil (SRGO) and its desulfurized oil (HSRGO), their selective activities toward above reactions were compared since the best combination of two catalysts in two-layer bed was expected to achieve deep HDS of SRGO rather easily. NMA-1 removed reactive sulfur species effectively and refractory sulfur species moderately but failed to remove nitrogen species in SRGO. The catalyst was not effective to remove refractory sulfur species in HSRGO to achieve the total sulfur level of less than 10 ppm S in the second layer. NiMoS on acidified alumina (NMA-2) and NMASA1-70 removed nitrogen species very effectively but sulfur species in SRGO were not so efficiently removed. Both catalysts were very active for HSRGO to attain 10 ppm sulfur level. Rapid HDN in SRGO over the catalysts appears to retard HDS of SRGO, leaving even reactive sulfur species unreacted. Among the catalysts, NiMoASA2-50 was very active for all reactions to achieve less than 10 ppm from SRGO via two stages. The rapid HDN over the particular catalyst allowed the effective HDS after the rapid completion of HDN. Such contrast activities of four catalysts are compared as regards their surface area, acidity and NiMoS location on the support particles. NiMo on alumina or on the border of acidified alumina and silica of right content is most activated for HDN as well as HDS. Acidity appears essential for HDN. Larger surface area of the particular alumina–silica support is certainly favorable for both HDS and HDN. The larger content of silica in NMASA1-70 may not be favorable for high dispersion of NiMoS to show higher activity for HDS while HDN progresses.

Characterization of Natural Wetland Soils Receiving Acid Mine Drainage

A proposed section of Appalachian Corridor H will pass through an area of the Beaver Creek watershed in Tucker County, WV previously mined for the acid-producing Upper Freeport coal. Presently, partially-reclaimed spoils from past mining activities are generating acid mine drainage. Wetlands adjacent to the spoils are supporting vegetative communities and they appear to be naturally treating the drainage. We characterized soils of the acid mine drainage- impacted wetlands and non-impacted wetlands to establish baseline soil status and to compare the acid mine drainage-impacted soils and non-impacted soils. We analyzed soil samples for pH, sulfate, acid volatile sulfides, chromium reducible sulfides, organic sulfur, total sulfur, total carbon, and total iron. Platinum redox electrodes were placed in some of the wetland soils to assess near surface redox chemistry. Wetlands receiving acid mine drainage generally contained higher levels of total sulfur, and the sulfur in these wetlands was more likely to be in the form of acid volatile sulfides, sulfate, and/or chromium reducible sulfides. Chromium reducible sulfides ranged from 0.0 to 103.4 umol g -1 and acid volatile sulfides ranged from 0.0 to 32.3 umol g -1 in all wetlands. The carbon content in wetlands receiving acid mine drainage was generally lower than the non-impacted wetlands and the iron content was generally higher in the acid mine drainage- impacted wetlands. Redox values indicated that conditions are present in impacted wetlands for iron and sulfur reduction to occur.

Microbial desulfurization of fuel oil

Culture conditions of desulfurization microbes were investigated with a bioreactor controlled by computer. Factors such as pH, choice of carbon source, optimal concentrations of carbon, nitrogen and sulfur sources were determined. The addition of carbon in a culture with a constant pH greatly improved the growth of Rhodococcus. Cells and cell debris from microbes rested using a sulfur-specific pathway were used to desulfurize diesel oil treated by hydrodesulfurization (acquired from the Research Institute of Fushun Petroleum with total sulfur level at 205 μg/mL). Strains lawq, IG., X7B, ZT, ZCR, and a mixture of No. 5 and No. 6, were used in the biodesulfurization process. The reduction of total sulfur was between 10.6% and 90.3%.

Ultra-deep Hydrodesulfurization of Kerosene for Fuel Cell System. (Part 4). Improvement of Trace Sulfur Analyzer.

The reliability of total sulfur analysis near the limit of detection based on ASTM D4045 was improved by passing 10% CO 2 in H 2 . Analysis of less than 0.1 wtppm of sulfur is difficult due to adsorption of H 2 S on impurities of the ceramic tube even using a specially prepared pure ceramic tube that has been selected to reduce impurities in the original procedure. Analysis of single ppb levels of total sulfur in kerosene applying the optional OxyHydro procedure suffers from large overestimation error even using the pure ceramic tube. These problems were solved by a simple idea to block the adsorbing points with substitute adsorption with CO 2 in the conventional ceramic tubes. With additional improvements to suppress noise, the limit of detection was improved by 100-fold even using the conventional ceramic tubes.

Quantitative determination of sulfur compounds in FCC gasolines by AED. A study of the effect of catalyst type and catalytic conditions on sulfur distribution

AbstractThe identification and quantification of sulfur‐containing compounds in gasoline has become an area of interest because of impending legislation regulating total sulfur levels in these fuels. To study the effects of catalyst type and catalytic conditions on gasoline sulfur distribution, a method has been developed employing both the compound‐independent and element‐specific response of the atomic emission detector (AED). Calibration and quantification can be accomplished even where standards are not available, owing to the nature of the AED response.Compounds were separated on a thick film polydimethylsiloxane column. An external calibration curve was applied to the area responses of individual sulfur components in the sulfur chromatogram, and the concentrations of each were calculated. Summation of these sulfur concentrations over the gasoline range yields the total sulfur content of the gasoline.The method is applicable to the determination of these compounds in raw crude oils, finished gasolines, fluid cracking catalyst (FCC) unit gasolines, and fluid catalytic cracking “model” compound studies. A prefractionating column was employed to remove heavy (&gt;C13) materials; prefractionation is not, however, necessary for distilled or commercial gasoline samples. Detection limits, linearity, detector stability, and accuracy are discussed.

Foliar mineral composition, fertilization and dieback of Norway spruce in the Belgian Ardennes.

Needles from healthy Norway spruce (Picea abies (L.) Karst.) at Willerzie in the West Ardennes and from trees with symptoms of dieback at Langesthal in the East Ardennes were analyzed by age class for mineral composition. Both stands were on acid oligotrophic soils. At Willerzie, needles were sampled from plots fertilized 12 to 17 years earlier (dolomitic lime plus N, P and K) as well as unfertilized plots. Effects of fertilization included increased levels of calcium, manganese, phosphorus, and copper and reduced levels of total sulfur, sulfate-S, sulfate-S:total S, potassium and aluminum. Levels of calcium, magnesium, copper and boron were low at both sites and, at Langesthal, calcium and magnesium may have been deficient. Sulfur level was normal at Willerzie, but at Langesthal, mean sulfur content for needles of all age classes was 198 mg 100 g(-1) dry weight, a level that may be toxic. In older needles, the N:S ratio at Langesthal was below the threshold value of eight reported to be necessary for healthy growth. Other symptoms of stress observed were high sulfate-S:total S and nitrate-N:total N ratios. At Langesthal, manganese level was probably adequate although only one-fifth the level at Willerzie. Levels of aluminum and iron were very high at both sites. Most of the iron and much of the aluminum occurred as a surface deposit that could be removed by washing the needles in chloroform.