96/03489 Effect of nitric acid attach on the organic sulfur content of coals

1996 ◽  
Vol 37 (4) ◽  
pp. 250
Keyword(s):  
Nitric Acid ◽  
Sulfur Content ◽  
Organic Sulfur

Comparison of the Bromine and Nitric Acid Methods of Estimating Sulfur in Acetone Extracts

1947 ◽  
Vol 20 (1) ◽  
pp. 315-319 ◽  
Author(s):  
J. F. Morley ◽  
J. R. Scott
Keyword(s):  
Nitric Acid ◽  
Sulfur Content ◽  
Elementary Sulfur ◽  
Total Sulfur ◽  
Total Sulfur Content ◽  
Acid Method ◽  
The Difference ◽  
The One ◽  
Acetone Extracts ◽  
Free Sulfur

Abstract From the experiments described, it appears that neither the bromine method nor the nitric acid method is perfectly satisfactory, for the following reasons. (1) Neither method gives the true free sulfur in rubbers containing sulfur-bearing accelerators, as these cause positive errors of anything up to 0.2–0.3 per cent. (2) The nitric acid method does not give the true free sulfur in rubbers, without sulfur-bearing accelerators, because the result includes some of the sulfur combined with the rubber “resins” the tests do not show definitely whether this applies also to the bromine method. (3) Neither method gives the total sulfur in the acetone extract, since some of the sulfur combined with the “resins” is not included in the result; the presence of certain sulfur-bearing accelerators increases the error. The statement previously referred to (loc. cit.), that the bromine method approximates more nearly to the elementary sulfur content and the nitric acid method more nearly to the total sulfur content of the extract, appears to be a correct generalization. In most cases, however, the difference between the results obtained by the two methods would be less than 0.1 per cent. In respect of simplicity and rapidity of working, the bromine method has the advantage over the nitric acid method, and therefore in all ordinary circumstances is the one to be recommended.

scholarly journals Effects of organic sulfur on oxidation spontaneous combustion characteristics of coking coal

2021 ◽  
pp. 014459872110490
Author(s):  
Fei Gao ◽  
Zhe Jia ◽  
Mei-ling Qin ◽  
Xiao-gang Mu ◽  
Yi-fei Teng ◽  
...  
Keyword(s):  
Sulfur Content ◽  
Photoelectron Spectroscopy ◽  
Spontaneous Combustion ◽  
Characteristic Temperature ◽  
Combustion Process ◽  
Oxidation Products ◽  
Organic Sulfur ◽  
Scanning Calorimetry ◽  
Clean Coal ◽  
Spontaneous Combustion Of Coal

Research on the spontaneous combustion of coal caused by sulfur has always been focused on pyrite in coal but has rarely considered the influence of organic sulfur. In this paper, coal samples, rather than model compounds, were used to study the influence of organic sulfur content in coal on its spontaneous combustion process. The results of X-ray photoelectron spectroscopy and thermogravimetry, differential scanning calorimetry, and mass spectrometry indicate that organic sulfur in Shuiyu clean coal exists in forms of mercaptan, thioether, sulfone (sulfoxide), and thiophene. With the decrease of organic sulfur content, the characteristic temperature points and the peak values of the exothermic curves in the process of coal oxidation spontaneous combustion all shifted toward higher temperatures. The ignition activation energy of coal also increased, and the initial and peak gas evolution temperatures of the oxidation products shifted toward higher temperatures. These findings suggest that the reduction of organic sulfur content can inhibit the oxidation process and spontaneous combustion tendency of coal. This effectively reveals the mechanism of the spontaneous combustion of coal and is of great significance to future studies in this field.

Hydrodesulfurization of Spanish Lignite with a High Organic Sulfur Content

1989 ◽  
Vol 7 (1-2) ◽  
pp. 47-54 ◽  
Author(s):  
ANA B. GARCIA ◽  
HAROLD H. SCHOBERT
Keyword(s):  
Sulfur Content ◽  
Organic Sulfur

scholarly journals Microbial Desulfurization of Gasoline in a Mycobacterium goodii X7B Immobilized-Cell System

2005 ◽  
Vol 71 (1) ◽  
pp. 276-281 ◽  
Author(s):  
Fuli Li ◽  
Ping Xu ◽  
Jinhui Feng ◽  
Ling Meng ◽  
Yuan Zheng ◽  
...  
Keyword(s):  
Sulfur Content ◽  
Immobilized Cells ◽  
Industrial Applications ◽  
Cell System ◽  
Mass Spectrometry Analysis ◽  
Organic Sulfur ◽  
Potential Candidate ◽  
Immobilized Cell ◽  
Spectrometry Analysis ◽  
Mycobacterium Goodii

ABSTRACT Mycobacterium goodii X7B, which had been primarily isolated as a bacterial strain capable of desulfurizing dibenzothiophene to produce 2-hydroxybiphenyl via the 4S pathway, was also found to desulfurize benzothiophene. The desulfurization product was identified as o-hydroxystyrene by gas chromatography (GC)-mass spectrometry analysis. This strain appeared to have the ability to remove organic sulfur from a broad range of sulfur species in gasoline. When Dushanzi straight-run gasoline (DSRG227) containing various organic sulfur compounds was treated with immobilized cells of strain X7B for 24 h, the total sulfur content significantly decreased, from 227 to 71 ppm at 40�C. GC flame ionization detection and GC atomic emission detection analysis were used to qualitatively evaluate the effects of M. goodii X7B treatment on the contents of gasoline. In addition, when immobilized cells were incubated at 40�C with DSRG275, the sulfur content decreased from 275 to 54 ppm in two consecutive reactions. With this excellent efficiency, strain X7B is considered a good potential candidate for industrial applications for the biodesulfurization of gasoline.

scholarly journals Extreme 13C-depletions and organic sulfur content argue for S-fueled anaerobic methane oxidation in 2.72 Ga old stromatolites

2019 ◽  
Vol 244 ◽  
pp. 522-547 ◽  
Author(s):  
Kevin Lepot ◽  
Kenneth H. Williford ◽  
Pascal Philippot ◽  
Christophe Thomazo ◽  
Takayuki Ushikubo ◽  
...  
Keyword(s):  
Methane Oxidation ◽  
Sulfur Content ◽  
Anaerobic Methane Oxidation ◽  
Organic Sulfur

Evolution of the organic sulfur and other components during nitric acid leaching of Mequinenza coal

Fuel ◽  
1997 ◽  
Vol 76 (14-15) ◽  
pp. 1445-1450 ◽  
Author(s):  
Ramón Álvarez Rodríguez ◽  
Carmen Clemente Jul ◽  
Dulce Gómez-Limón
Keyword(s):  
Nitric Acid ◽  
Acid Leaching ◽  
Organic Sulfur ◽  
Nitric Acid Leaching

scholarly journals Enrichment of Li–Ga–Zr–Hf and Se–Mo–Cr–V–As–Pb Assemblages in the No. 11 Superhigh Organic Sulfur Coal from the Sangshuping Coal Mine, Weibei Coalfield, Shaanxi, North China

Energies ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 6660
Author(s):  
Jing Li ◽  
Peng Wu ◽  
Guanghua Yang ◽  
Lei Pan ◽  
Xinguo Zhuang ◽  
...  
Keyword(s):  
Sulfur Content ◽  
Coal Mine ◽  
North China ◽  
Negative Impact ◽  
Hydrothermal Activity ◽  
Depositional Environments ◽  
Hydrothermal Fluids ◽  
Organic Sulfur ◽  
Sediment Provenance ◽  
High Sulfur Content

Superhigh organic sulfur(SHOS) coals have currently attracted great attention due to their typical depositional environments and formation history as well as their great negative impact on the ecosystem. This study investigated the geochemistry of the No. 11coalof the Late Carboniferous Taiyuan Formation from the Sangshuping coalmine, Hancheng miningarea, Weibei coalfield, Shaanxi, North China. The No. 11 coal is a high-sulfur coal with a large proportion of organic sulfur content (3.7 to 5.5%, avg. 4.4%) and belongs to typical SHOS coal. The high sulfur content in the Sangshuping coal mine has been mainly caused by the combined influences of seawater and hydrothermal fluids. The SHOS in No. 11 coal was formed in the Fe-poor and S-rich high-marine influenced occlusive environment. During the late coalification stage, a high proportion of pyritic sulfur was formed due to sufficient Fe supply from the Fe–S-rich epigenetic hydrothermal fluids. The No. 11 SHOS coal is enriched in Li–Ga–Zr–Hf and Se–Mo–Cr–V–As–Pb element assemblages. The sediment provenance of the Sangshuping coal mine is predominantly felsic–intermediate rocks from both the Yinshan and Qinling Oldland. However, the elevated concentrations of critical elements (Li, Ga, Zr, and Hf) in the No. 11 coal are primarily inherited from the Yinshan Oldland. The enrichment of the Se–Mo–Cr–V–As–Pb assemblage in No. 11 coal can be ascribed to the influence of both seawater and epigenetic hydrothermal activity.

scholarly journals POST-COMBUSTION COAL DESULFURIZATION Review

Eksergi ◽  
2020 ◽  
Vol 17 (2) ◽  
pp. 79
Author(s):  
Silky Amanda Yuniar ◽  
Edy Nursanto ◽  
Rika Ernawati
Keyword(s):  
Sulfur Content ◽  
Coal Combustion ◽  
Sulfur Oxidation ◽  
Organic Sulfur ◽  
Inorganic Sulfur ◽  
Coal Desulfurization ◽  
Burning Coal ◽  
Cleaning Technology ◽  
Sulfur In Coal ◽  
So2 Gas

The sulfur content in coal ranges from 0.5 to 5%, and it is an impurity that must be removed before burning coal, due to the toxic effects and acid rain caused by SO2 gas generated from sulfur oxidation. Sulfur cleaning technology can be carried out on coal before combustion (pre-combustion), and can reduce the inorganic sulfur content by up to 50%; however, it cannot reduce the organic sulfur content. Therefore, the industry relies on post-combustion desulfurization to remove SO2 from the gas from coal combustion. The aim of the coal desulfurization review is to direct desulfurization research to be efficient and effective, as well as to be environmentally friendly. Sulfur in coal consists of organic sulfur and inorganic sulfur. Coal inorganic sulfur consists of pyrite (FeS2), sulfate, and sulfide. The largest composition is pyrite. Organic sulfur consists of hetero-atomic and heterocyclic (thiophenic) macromolecules that bind N and O atoms, aromatic sulfides, and aromatic disulfides (small amounts). Inorganic sulfur can easily be separated from coal by means of flotation, microwave energy, magnetic forces, ultrasonic energy, and as well as microorganisms. Meanwhile, organic sulfur cannot be separated from coal by using the methods used in the inorganic sulfur separation process. Organic sulfur can be removed by chemical and biodesulfurization, however, this process is inefficient for industrial scale. The most recommended method is the absorption of SO2 gas in the gas from coal combustion, or post-combustion desulfurization. Various methods have also been investigated to separate SO2 gas, and more details will be described in this paper.

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