Analysis Of Sulfur Content Research Articles

Upgrading of kraft lignin pyrolysis products: Managing sulfur impurities

Pyrolysis stands as a powerful method for the valorization of biomass like kraft lignin, an aromatic-rich and sulfur-containing polymeric by-product from the pulping industry. Sulfur in the raw matrix is released during thermal processes and is redistributed in pyrolysis products. However, the presence of sulfur lowers the quality of products due to its corrosive and toxic character. In this work, commercial activated carbons have been used as adsorbents to remove the main sulfur compounds from the gas phase (i.e., CH3SH, COS, H2S). The analysis of sulfur content in biochar has been performed through SEM-EDXS, while the sulfur content in oils has been obtained by GC–MS analysis. The adsorption of sulfur on the activated carbon bed results in an enhancement of the release of sulfur in the gas phase from 34 % without activated carbon to 44 %. Up to 88 % of H2S removal is achieved after the adsorption step, together with a reduction of the overall sulfur content in the bio-oil rich in intermediates such as guaiacols and alkylated phenols. The residual sulfur contained in the liquid product is lowered to 3 % of the total sulfur in the system, thus improving the quality of the liquid pyrolysis product. This process limits the amount of sulfur in the gas and improves its quality and market value. At the same time, this results in a redistribution of sulfur in pyrolysis products such as bio-oil, improving its range of application as a source of chemical intermediates from kraft lignin.

INFLUENCE OF TECHNOLOGICAL PARAMETERS ON THE COMPOSITION AND PROPERTIES OF PETROLEUM COKE

This study is devoted to studying the complex process of producing coke from heavy oil residues using previously developed experimental approaches and using analytical methods of analysis. The purpose of the study is to produce low-sulfur coke by thermal processing of heavy oil residues in the presence of waste motor oils. The resulting coke was analyzed by various physicochemical methods. The composition and structure of the resulting coke were studied using Raman spectroscopy methods. As a result of the analysis, the predominance of polyaromatic compounds and olefins in the coke composition was revealed. Electron microscopy techniques provided a visual representation of the microstructure and morphology of coke samples obtained both in the presence and absence of a recycling agent. Significant results were obtained by measuring the specific surface area of coke, which highlight the significant influence of temperature fluctuations on its characteristics of coke. It is noteworthy that the specific surface area of micropores varies significantly – from 16 to 600 m2/g. The results of the analysis of sulfur content showed the possibility of its thermal dehydration, which should lead to an improvement in the quality of coke. In addition, it has been shown that conducting the experiment in the presence of a recycling agent significantly increases the yield of coke and opens up prospects for more efficient use of heavy oil residues. Taken together, the results provide valuable insight into the intricacies of producing low-sulfur coke from heavy petroleum residues. In addition to industrial significance, this research also has environmental significance, since it proposes an approach that allows not only to maximize the use of secondary resources, but also to reduce the sulfur content in coke, which will help limit the environmental impact of industrial processes.

Analisis Kualitas Batubara Bonto Matinggi Sulawesi Selatan Untuk Kebutuhan Industri Semen

Coal in Indonesia is widely used for both export and domestic industrial needs. Domestically, it is widely used for the textile industry, power plants, and the cement industry. Coal consumption for the cement industry in Indonesia in 2022 is up to 15 million tons. In the cement industry, coal is used as a basic material for fuel in kilns. For its utilization, coal needs to know its properties. These properties can be known by proximate analysis, sulfur content analysis and calorific value. Therefore, this research aims to find out and determine whether the quality of Bonto Matinggi coal is in accordance with the coal specifications needed in the cement industry. The research method was carried out by taking two coal samples directly in the research area, namely SA I coal sample and SA II coal sample. The coal samples were then prepared and further analyzed. Analysis of coal sample quality was carried out by proximate, sulfur and calorie analysis methods. The results of proximate analysis show that the moisture content in air dried both samples have a value that is not too significant with an average value of 6.29% adb; ash content of 19.99% adb; volatile matter of 46.79% adb and fixed carbon of 39.86% adb as well as sulfur content of 0.39% adb and calories with an average of 4,692.92 cal/g. The coal in the study area does not qualify as a basic material for fuel in kilns in the cement industry. The coal in the study area, if classified according to the Classification of in Seam Coal 1998, is classified as low grade coal (according to ash content) and the coal rank includes bituminous rank (medium rank).

Improving the Analysis of Sulfur Content and Calorific Values of Blended Coals with Data Processing Methods in Laser-Induced Breakdown Spectroscopy

In Situ monitoring of the calorific value of coal has the advantage of reducing the amount of unburned carbon by injecting an appropriate amount of combustion air immediately to induce complete combustion. High sulfur concentrations cause severe environmental problems such as acid rain. In order to estimate the calorific value and measure the sulfur concentration, a new powerful technique for mixed coals was studied. Laser-induced breakdown spectroscopy (LIBS) does not require sample preparation. Several blended coals were used for the experiment to replicate the actual coal-fired power plant conditions. Two well-known data processing methods in near-infrared spectroscopy have been adopted to enhance the weak sulfur emission lines. The performance of the partial least square regression model was established by the parameters such as coefficient of determination, R2, relative error, and root mean square error (RMSE). The RMSE average was compared with the results of previous studies. As a result, the values from this study were smaller by 6.02% for the calibration line and by 4.5% for the validation line in near-infrared spectroscopy. The RMSE average values for calorific values were calculated to be less than 1%.

The effect of the addition of mangrove wood charcoal to reduce sulfur content in coal

Coal in Sulawesi, especially in South Sulawesi, has several shortcomings since it contains sulfur and produces a high ash content that affects the environment. Desulphurization with High-Temperature Combustion Methods is a sulfur content analysis method using the SC-144DR Dual Range Sulfur Analyzer coal tool, which is one of the methods used to reduce sulfur in coal. Based on the results of the study, it was obtained: a mixture of coal with mangrove wood charcoal with the composition of 25% Sin coal + 75% MWC = 0.067% sulfur content, 50% Sin coal + 50% MWC = 0.089% sulfur content and 75% Sin coal + 25% MWC = 0.107% sulfur content. These results indicate that the more addition of mangrove charcoal, the lower sulfur content in the coal. Decreasing sulfur content can improve the quality of the coal produced, especially in combustion systems that affect the environment.

Daur Ulang Cell Tube X - Ray Analyzer dengan Membuat Alat Pemisah Cell Tube di Laboratorium PT Pertamina (Persero) RU III Plaju - Palembang

Laboratory production Analyst & Gas section in Refinery Unit III,   Laboratory production analyses of samples water, gas, chemicals, scale, waste water and oil analysis samples are chemicals, which are derived from the refinery and its surrounding environment. In the analysis of the example of oil, one of the parameters of its analysis is the SULFUR CONTENT. Analysis of the sulfur content is done using instruments, namely x-ray SULFUR ANALYZER, X-ray sulfur analyzer to operate using this Cell Tube as a sample container will be analyzed. During this analysis is completed, cell Tube disposed of along with its contents to the shelter of the waste materials are toxic and dangerous. This can hinder the process of lifting, loading and unloading and distributing fuel to various corners of the other areas. Because the certificate of its quality controlcould not be made because there is one very important reply analysis specified fuel products i.e. analysis of sulfur content could not be analyzed. If supplies cell tube is exhausted due to increased demand for analysis of sulfur and quite significant. By using simple tools and using the principle of the lever, the eventual cell tube former can split and cleaned so that it can be reused

Artificial Neural Network Prediction of Sulfur Content of Diesel fuel from its Physical Properties

The sulfur content is important in engineering calculations, so this study has two major purposes. The first purpose of the study is to predict the sulfur content from its physical properties by using artificial neural network to decrease time and cost spent on experimental analysis of sulfur content, and the second purpose is to find the simplest formula to predict the sulfur content. Artificial Neural Network is applied as a black-box type modelling for sulfur content prediction of diesel fuel. The experimental data used in this study is obtained from Erbil power station. In this study, the Levenberg-Marquardt training algorithm is used to train the neural network and to predict the sulfur content. It was observed that the ANN model can predict the sulfur content of diesel quite well with correlation coefficient (R) 0.9813. The prediction Mean Square Error was between the targets values and the outputs values were obtained 0.000339 by the matlab software. The findings obtained in this study indicated that the designed neural network performs quite well in the prediction of sulfur content of diesel fuel from its physical properties.

Calcium Carbonate Crystal Shapes Mediated by Intramineral Proteins from Eggshells of Ratite Birds and Crocodiles. Implications to the Eggshell’s Formation of a Dinosaur of 70 Million Years Old

In this contribution we want to show how the intramineral proteins affect the crystal morphology of calcite crystals grown in vitro. Intramineral proteins from emu eggshells and two crocodile species were isolated, purified by ultrafast liquid chromatography, and characterized by biochemical and biophysical methods. We saw that the crystal habit of calcite was modified when intramineral proteins were present at certain concentration. Therefore, all crystal species were individually characterized by scanning electron microscopy (SEM) and by electron diffraction with an electron-reduced dosage in transmission electron microscopy. Additionally, transversal SEM micrographs of eggshells of four types of species, namely, emu, crocodile, hen, and dinosaur (70 million years old), were compared to track the changes produced by the interacting intramineral proteins. Finally, the organic sulfur content analysis of these eggshells was performed by using X-ray absorption techniques like X-ray fluorescence and X-ray absorption near-edge structure. From the analyses of the dinosaur eggshells, these X-ray absorption data showed a very characteristic organic sulfur bonding similar to that semiessential proteogenic amino acid l-cysteine, which implies that there is a possibility of having a very old intramineral protein similar to those found in emu and crocodiles.

Research on Prediction Model of End Sulfur Content for Converter Smelting

Converter smelting medium-low carbon ferrochrome replaces electronic by oxygen and reduces production energy consumption greatly. Medium-low carbon ferrochrome end sulfur content analysis is necessary to determine the product quality. Now we still use the product sampling, laboratory analysis to determine end sulfur content, which can not realize online monitoring. According to this status, a PLSBP prediction model of end sulfur content has been established based on particle swarm algorithm, which combined partial least squares method and BP neural network. At the same time, A feedback compensation model has been established by dichotomy, which avoided the model failure caused by raw material quality change. The simulation results showed that the hit rate of prediction model was 96.67% within the absolute error, 90% within relative error. High precision was achieved, which provided an important theoretical basis to improve product quality and optimize the production process.

Quantitative determination of sulfur content in diesel using THz-TDS technology

The frequency-dependent absorption characteristics of diesels with different sulfur content have been studied in the spectral range of 0.2-1.5 THz by the terahertz time-domain spectroscopy(THz-TDS).The absorption coefficient presented a regular change with the THz frequency and sulfur content,and the absorption coefficient increases with the frequency at the same concentration,vice versa.A nonlinear multivariate model was established and the sulfur content in diesel can be confirmed easily by means of the measured THz frequency-dependent absorption coefficient.The results made the quantitative analysis of sulfur content in diesel possible by THz-TDS technology and indicated the bright future in practical application.

정속항해 시 함정 주 추진 디젤엔진의 배기가스 배출량 예측

Abstract: This study was focused on the estimations of air pollutants, such as PM(Particulate matters), SOx(Sulfur Oxides), CO 2 (Carbon diOxides) and NOx(Nitrogen Oxides), from a diesel propulsion engine installed on a naval vessel. Legislative and regulatory actions for exhaust emissions from ships are being strengthened in international communities and national governments to protect human health and the environment. In this context, various technologies have been developed from all of the nations of the worldto meet strict standards. These regulations are based on commercial ship applications and according to size,but are not suitable for military naval vessels, which have much different engine operating conditions andhull architectures. Additionally, there is no international emission control system for military ships. Emission factors have been updated for commercial ship types from work at various research institutes; however, it is difficult to develop emission factors for military vessels because of their characteristics. In this paper, exhaust emissions from diesel engines installed on naval vessels under steady navigation condition were estimated with emission inventory methodology applied to ocean going vessels using fuel-based methods and fuel sulfur content analysis.

Synthesis and properties of PdO/CeO2-Al2O3 catalysts for methane combustion

This study focuses on the loading of catalytic materials, e.g., palladium on the surface of supporting materials, with the aim to obtain catalysts with high activity for methane combustion. The catalyst PdO/CeO2-Al2O3 was prepared by impregnation under ultrasonic condition. The effect of different activation methods on the activity of catalysts for methane catalytic combustion was tested. The properties of reaction and adsorption of oxygen species on catalyst surface were characterized by H2-temperature programmed reduction (H2-TPR), and O2-temperature programmed desorption (O2-TPD). Furthermore, the sulfur tolerance and sulfur poisoning mode were investigated. The results indicate that the catalyst PdO/CeO2-Al2O3 activated with rapid activation shows higher activity for methane combustion and better sulfur tolerance. The result of sulfur content analysis shows that there is a large number of sulfur species on the catalyst’s surface after reactivation at high temperature. It proves that the activity of catalysts cannot be fully restored by hightemperature reactivation.

Optimization of digestion parameters for analysing the total sulphur of mine tailings by inductively coupled plasma optical emission spectrometry

The oxidation of sulphidic mine tailings and consequent acid generation poses challenges for the environment. Accurate and precise analysis of sulphur content is necessary for impact assessment and management of mine tailings. Here, the authors aim at developing a rapid and easy digestion procedure, which may analyse and measure the total amount of sulphur in mine tailings by using inductively coupled plasma. For evaluating effects of several variables, the researchers used a univariate (analysis of variance (ANOVA)) strategy and considered factors such as composition of the acid mixture, heating time, and refluxing device to optimize the performance. To do the experiment, the researchers have used two certified reference materials (KZK-1 and RTS-2) and samples of tailings from Musselwhite mine. ANOVA result shows that heating time is the most influencing factor on acid digestion of the reference materials whereas in case of a digestion of tailings sample, hydrochloric acid proved to be the most significant parameter. Satisfactory results between the measured and referenced values are found for all experiments. It is found that the aqua regia (1ml HNO(3) + 3ml HCl) digestion of 0.1g of samples after only 40min of heating at 95°C produced fast, safe, and accurate analytical results with a recovery of 97% for the selected reference materials.

The durability of alumina supported Pd catalysts for the combustion of methane in the presence of SO 2

In the present work, the 1.0 wt% Pd/γ-Al 2O 3, 1.0 wt% Pd/10 wt% CeO 2/γ-Al 2O 3 and 1.0 wt% Pd/10 wt% Ce 0.6Zr 0.4O 2/γ-Al 2O 3 catalysts were prepared and used for the catalytic combustion of methane. The durabilities of the three catalysts were investigated based on the phenomena of SO 2 poisoning in methane catalytic combustion. The presence of SO 2 in the reaction gases resulted in an increase of 70–250 °C in light-off temperature for methane conversion over all the catalysts. The sulfates could be formed below and decomposed above 600–700 °C in the reaction over the catalysts, which led to the inhibition and recovery of the catalytic activity, respectively. The introduction of CeO 2 or Ce 0.6Zr 0.4O 2 decreased the decomposition temperature of sulfates by 50–100 °C. Sulfur accumulation on the catalyst surface was investigated by sulfur content analysis and TG measurements after pretreatment with SO 2. The saturated sulfur contents were all about 5 wt% for the three catalysts. In spite of sulfur poisoning, no obvious changes in the particle morphologies and sizes were observed for the fresh and used catalysts.

Effect of the addition of Au in zirconia and ceria supported Pd catalysts for the direct synthesis of hydrogen peroxide

Mono- and bimetallic palladium–gold catalysts supported on zirconia and ceria, both sulfated and non-sulfated, are tested for the direct synthesis of hydrogen peroxide under very mild (1 bar and 20 °C) and non-explosive conditions. Catalysts are characterized by N 2 physisorption, sulfur content analysis, temperature programmed reduction (TPR), Fourier transmission infrared (FTIR) spectroscopy and high resolution transmission electron microscopy (HRTEM). Catalytic tests are carried out with different gas mixtures and after various pretreatments. Best catalytic results are observed using sulfate doped zirconia samples and H 2/O 2 mixtures containing a large excess of oxygen. Monometallic gold catalysts are completely inactive, while the addition of gold to palladium improves both the productivity and the selectivity of the process. Surface oxidized Pd and Pd–Au catalysts pretreated with hydrogen and oxygen show higher activity and selectivity with respect to non-pretreated samples. A mechanistic explanation is proposed.

Ex situ hydrolytic degradation of sulfonated polyimide membranes for fuel cells

Ex situ hydrolytic stability of sulfonated polyimide (s-PI) membranes for fuel cells was studied depending on structural and external parameters including the ion exchange capacity, the block character, the temperature and the hydrogen peroxide concentration. Infrared spectroscopy was used to identify and quantify the chemical modifications such as the loss of imide functions and of ionic monomers. The decrease in ion exchange capacity due to the elution of sulfonated oligomers was confirmed by sulfur content analysis. A complete hydrolysis of some of the imide functions is observed leading to polymer chain scissions and to the loss of the mechanical properties. It is shown to be a thermo activated process and the activation energy (60kJ/mol) is found in good agreement with the value determined from fuel cell lifetimes. The degradation in fuel cell conditions is similar but faster than in pure water. The same kinetic can be reproduced ex situ by addition 0.05% of hydrogen peroxide.

Influence of Activation and the HDS Reaction on the Structure of Magnesium Fluoride-Supported Ru Catalysts Derived from Ruthenium Chloride Hydrate

The effect of activation conditions and the hydrodesulfurization (HDS) process on the structure of Ru/MgF2 prepared from RuCl3⋅nH2O precursor catalysts was studied. During the first 6-7 h of the HDS process significant differences in activities were detected between samples pretreated in 50% H2S/H2 and in 50% H2S/He. During this transient time, the Ru/MgF2 catalyst pretreated in 50% H2S/H2 increased in activity while the activity of that pretreated in H2S/He decreased. XRD, TPR and quantitative analysis of sulfur content revealed that directly after activation in H2S/He crystalline ruthenium sulfide is the main component of the surface, whereas after activation in H2S/H2 both RuS2 and metallic Ru are present on the surface. These differences decrease during the thiophene HDS process. Despite the different pretreatment conditions, the composition of the surface tends to “equilibrate”, which results in similar activity after prolonged reaction time.

Fractionation of low-molecular-mass heparin by centrifugal partition chromatography in the ion-exchange displacement mode

Centrifugal partition chromatography in the ion-exchange displacement mode allowed a preparative and efficient fractionation of low-molecular-mass heparins from enoxaparin sodium. Amberlite LA2 — a lipophilic liquid secondary amine — was chosen as a weak anion exchanger. The biphasic system methyl isobutyl ketone–water was selected. Protonated LA2 (10%, v/v) was added to the organic stationary phase. Hydroxide (Na +, OH −) was chosen as a displacer in the aqueous mobile phase. The observed pH and concentration profiles are typical of displacement chromatography, as supported by numerical simulation. The Dubois test for the analysis of sugar content and an analysis of sulfur content (and consequently sulfatation rate) were carried out to monitor the effectiveness of the procedure. Moreover, the fractions were analyzed by high-performance size-exclusion chromatography and the 1H NMR spectra confirmed the fractionation of the sample of enoxaparin sodium.

New solid superacid catalysts for n-butane isomerization: γ-Al 2O 3 or SiO 2 supported sulfated zirconia

Solid superacid catalysts SO 4 2−/ZrO 2 (SZ) supported on γ-Al 2O 3 and SiO 2 (named SZ/Al 2O 3 and SZ/SiO 2, respectively) were prepared by an impregnation method. Their catalytic behaviors of for n-butane isomerization at low temperature in steady state system and at high temperature in flow system were studied. Large improvements of catalytic activities were observed on the SZ/Al 2O 3 catalysts. In the flow system, the steady activity of the most active sample, 60% SZ/Al 2O 3, is 2.5 times more active than that of the bulk SZ. However, the activities of the SZ/SiO 2 catalysts are lower than that of bulk SZ. The texture properties of the catalysts were studied by the methods of XRD and the adsorption of N 2. Experimental results of sulfur content analysis and IR of adsorbed pyridine show that the acid strength and amount of strong acid sites on 60% SZ/Al 2O 3 sample are higher than those on bulk SZ, while the amount of acid sites is lower on 60% SZ/SiO 2. The different activities for the SZ/Al 2O 3 catalysts and the SZ/SiO 2 catalysts are due to the differences of superacidity.

The effect of Ni loading and the sulfidation temperature on the structure and catalytic activity of Ni [sbnd]W hydrodesulfurization catalysts

The effect of nickel concentration and sulfiding temperature on the type and distribution of the surface species and on the dispersion in a series of alumina-supported Ni W hydrodesulfurization (HDS) catalysts were investigated by temperature programmed reduction (TPR), diffuse reflectance spectroscopy (DRS), dynamic O 2 and NO chemisorption (DOC, DNOC), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), sulfur content analysis and thiophene HDS reaction. In the thiophene HDS reaction, the Ni W/γ-Al 2O 3 system showed a strong synergistic behavior. The maximum activity was achieved at about Ni/(Ni + W)= 0.6. When sulfiding temperature increased from 673 K to 1073 K, the activity monotonously decreased with the S-shaped curve. TPR results revealed three different nickel species, a highly dispersed NiO surface species, a mixed Ni W oxide phase, and a subsurface NiAl 2O 4-like phase. The nature and the amount of these species depended on nickel loading. DRS results provided complementary support for the presence of these species. The results of XRD, sulfur content analysis, DOC, DNOC, and XPS indicated that the sulfidability and the crystallinity of WS 2 increased with the increase in sulfidation temperature. The surface nickel species diffused into the bulk at high sulfidation temperature.