Extraction and desulfurization of chemically degraded coal with supercritical fluids: Final report, July 1, 1985-February 28, 1986

Technical Report · Thu May 01 04:00:00 EDT 1986

OSTI ID:7055713

Chen, J W; Muchmore, C B; Kent, A C

The overall goal of this research is to gain a better understanding of the phenomena of desulfurization of coal with supercritical alcohols. The specific research objectives, employing methanol and ethanol as supercritical solvents/reactants, were: (1) to study the chemical and physical transformations of coal; (2) to study the effect of pyrite in coal on desulfurization; (3) to study the effect of chemical pretreatment of coal on desulfurization; and (4) to study the effect of differing sulfur functional groups in coal, by comparing desulfurization attained with different coals. The degrees of physical and chemical transformations that occur when coals are desulfurized with supercritical alcohols appear to be related to the extent of desulfurization attained. Greater degrees of anisotropy (coke-like formation) are associated with greater desulfurization, implying that it is necessary for the coal matrix to undergo transformation to a fluid phase if high degrees of desulfurization are to be attained. It was found that chemical pretreatment of an Illinois No. 5 seam cleaned coal with nitric acid solution to remove the pyritic sulfur greatly enhances removed of organic sulfur during supercritical desulfurization with alcohols. Sulfur concentrations of the coal have been reduced to levels of about 0.1%. Given a run-of-mine value of 2.5% total sulfur, this represents an overall sulfur removal of more than 95%. These results suggest that the sequential processing of coal through an appropiate combination of physical and chemical cleaning steps can produce a solid fuel of high heating value, satisfactory volatile content, and total sulfur content which meets environmental standards. 10 refs., 9 figs., 2 tabs.

• Research Organization: Southern Illinois Univ., Carbondale (USA). Dept. of Mechanical Engineering and Energy Processes
• DOE Contract Number: FC22-83FE60339
• OSTI ID: 7055713
• Report Number(s): DOE/FE/60339-T41; ON: DE87002785
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010300 -- Coal
Lignite
& Peat-- Preparation-- (1987-)
010402* -- Coal
Lignite
& Peat-- Purification & Upgrading
ALCOHOLS
AUTOCLAVES
CALORIFIC VALUE
CARBONACEOUS MATERIALS
CHALCOGENIDES
CHEMICAL REACTIONS
CLEANING
COAL
COMBUSTION PROPERTIES
DATA
DESULFURIZATION
ENERGY SOURCES
ETHANOL
EXPERIMENTAL DATA
EXTRACTION
FOSSIL FUELS
FUELS
HYDROXY COMPOUNDS
INFORMATION
IRON COMPOUNDS
IRON SULFIDES
MATERIALS
METHANOL
MICROSCOPY
MINERALS
NUMERICAL DATA
OPTICAL MICROSCOPY
ORGANIC COMPOUNDS
PYRITE
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENT PROPERTIES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
SUPERCRITICAL GAS EXTRACTION
TRANSITION ELEMENT COMPOUNDS