Variation of char structure during anthracite pyrolysis catalyzed by Fe{sub 2}O{sub 3} and its influence on char combustion reactivity

Journal Article · Tue Sep 15 04:00:00 EDT 2009 · Energy and Fuels

DOI:https://doi.org/10.1021/ef900550w· OSTI ID:21261579

Gong, Xuzhong; Guo, Zhancheng; Wang, Zhi ^[1]

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1. Chinese Academy of Sciences, Beijing (China). State Key Laboratory of Multiphase Complex Systems

Effects of Fe{sub 2}O{sub 3} on the pyrolysis reactivity of demineralized anthracite were investigated by a thermo-gravimetric analyzer, indicating that pyrolysis reactivity of Fe{sub 2}O{sub 3}-loaded demineralized anthracite was higher than that of raw demineralized anthracite when temperature is over 500{sup o}C. Chars were prepared from the two coal samples in muffle with heating progress, and their structures were analyzed using SEM, FTIR, XRD, and Raman. FTIR results showed that absorption peaks of functional groups on the surface of char from catalytic pyrolysis at 700{sup o}C were more than that of char from noncatalytic pyrolysis. Raman results demonstrated values of (I{sub D3} + I{sub D4})/IG of chars from catalytic pyrolysis and noncatalytic pyrolysis were 4.76 and 3.86, respectively, indicating that ordering of the char was decreased by Fe{sub 2}O{sub 3}. XRD analysis revealed that diffraction angle of the 002 peak did not shift; however, L{sub a} and L{sub c} decreased, indicating degree of graphitization for microcrystalline structure of char from catalytic pyrolysis was decreased. The results of FTIR, XRD, and Raman of the char showed that catalytic pyrolysis improved the formation of free radicals, while hindered polymerization and forming of basic structure units. Finally, combustion reactivity of the three chars, including char of raw demineralized anthracite (char-A), char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite (char-B), and char of Fe{sub 2}O{sub 3}-loaded demineralized anthracite washed by HCl (char-C), was investigated using TG and indicated that their active order was char-B > char-C > char-A. The results corroborated that Fe{sub 2}O{sub 3} changed structure of anthracite char and improved combustion reactivity.

• OSTI ID: 21261579
• Journal Information: Energy and Fuels, Journal Name: Energy and Fuels Journal Issue: 9 Vol. 23; ISSN ENFUEM; ISSN 0887-0624
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
ANTHRACITE
CATALYSIS
CATALYTIC EFFECTS
CHARS
COMBUSTION PROPERTIES
GRAPHITIZATION
IRON OXIDES
MICROSTRUCTURE
PYROLYSIS
REACTIVITY
THERMAL GRAVIMETRIC ANALYSIS