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

Technical Report · Mon Jan 01 04:00:00 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
• OSTI ID: 5123836
• Report Number(s): FE-2030-TR-12
• Country of Publication: United States
• Language: English

Related Subjects

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