Thermochemistry and kinetics of oxygen interaction with microporous chars. Technical report 12. [199 references]

Technical Report · Mon Jan 01 00:00:00 EST 1979

DOI:https://doi.org/10.2172/5123836· OSTI ID:5123836

Ismail, I M.K.; Walker, P L

In processes involving the hydrogasification of coal, the coal is first exposed to hydrogen at elevated temperatures and pressures during which devolatilization and gasification of the more reactive parts of the coal occur. A microporous coal char, which is relatively unreactive, is also produced. The char, in turn, can be reacted with steam to generate the hydrogen needed in the first part of the process. Or the char, in part, can be used in a boiler to raise steam. In any case, characterization of coal chars and the relation of character to behavior during gasification and/or combustion is important. This report is primarily concerned with laying the experimental base for the measurement of the heat of interaction of a gas (oxygen in this case) with chars. Following the laying of this base, using a char produced from a reproducible polymer system, heats of interaction of oxygen with chars produced from American coals, ranging in rank from anthracite to lignite, were measured. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to study the exothermicity and kinetics of interaction between Saran chars and oxygen at selected isothermal temperatures in the range 75 to 850/sup 0/C. The combination of measuring heats of oxygen interaction with chars (using the DSC technique) and weight changes during the interaction opens up a valuable new technique to characterize coal chars. Heats of interaction at 100/sup 0/C are found to be related to rates of char gasification at higher temperatures. Both heats of interaction and gasification rates are, in turn, seen to increase sharply as the rank of coal from which the char is produced is decreased.

• Research Organization: Pennsylvania State Univ., University Park (USA). Coal Research Section
• DOE Contract Number: EX-76-C-01-2030
• OSTI ID: 5123836
• Report Number(s): FE-2030-TR-12
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
CHARS
CHEMICAL REACTIONS
COMBUSTION
GASIFICATION
SORPTIVE PROPERTIES
OXYGEN
CHEMISORPTION
ACTIVATION ENERGY
ADSORPTION HEAT
ADSORPTION ISOTHERMS
CHEMICAL REACTION KINETICS
COAL
COAL GASIFICATION
COAL RANK
EXPERIMENTAL DATA
HYDROGENATION
REACTION HEAT
THERMAL GRAVIMETRIC ANALYSIS
CARBONACEOUS MATERIALS
CHEMICAL ANALYSIS
DATA
ELEMENTS
ENERGY
ENERGY SOURCES
ENTHALPY
FOSSIL FUELS
FUELS
GRAVIMETRIC ANALYSIS
INFORMATION
KINETICS
NONMETALS
NUMERICAL DATA
OXIDATION
PHYSICAL PROPERTIES
PYROLYSIS PRODUCTS
QUANTITATIVE CHEMICAL ANALYSIS
REACTION KINETICS
SEPARATION PROCESSES
SORPTION
SURFACE PROPERTIES
THERMAL ANALYSIS
THERMOCHEMICAL PROCESSES
THERMODYNAMIC PROPERTIES
010404* - Coal
Lignite
& Peat- Gasification