TY - JOUR
T1 - The effect of HCl and NaOH treatment on structural transformations in a ball-milled anthracite after thermal and chemical processing
AU - Lueking, Angela D.
AU - Gutierrez, Humberto R.
AU - Jain, Puja
AU - Van Essandelft, Dirk T.
AU - Burgess-Clifford, Caroline E.
N1 - Funding Information:
Deepa Narayanan, and Apurba Sakti have participated at various stages in the preparation of these samples. Dr. John Badding and Mr. Jacob Caulkins of the PSU Chemistry Department provided equipment time and assistance to obtain the Raman Images. Dr. Peter Eklund has provided valuable discussion for interpretation of the Raman data. Drs. Harold Schobert and John Larsen suggested the possibility of the Diels Alder condensation reaction. Funding for the project has been provided by the Consortium for Premium Carbon Products from Coal (DEFC2603NT41874, Internal Agreement No. 2875-TPSU-DOE-1874), with partial support from PSU’s Energy Institute and Material Research Institute.
PY - 2007/10
Y1 - 2007/10
N2 - Nanocrystalline diamond (NCD) was observed after reactive ball milling of anthracite coal with cyclohexene, a high-temperature (1400 °C) thermal anneal, and a 4 M HCl treatment followed by a 10 M NaOH treatment. A crystalline carbon region was also observed when the thermal anneal was omitted. This crystalline region is highly unstable and converts to NCD and carbon onions via electron irradiation in the TEM. X-ray diffraction, Raman, ash content, and temperature-programmed oxidation (TPO) data suggest that tetrahedral amorphous carbon is formed during milling, iron carbides are formed during the thermal anneal step, and both the HCl and NaOH purification steps lead to changes in carbon structure. NaOH oxidizes metal carbides and this process may contribute to NCD formation.
AB - Nanocrystalline diamond (NCD) was observed after reactive ball milling of anthracite coal with cyclohexene, a high-temperature (1400 °C) thermal anneal, and a 4 M HCl treatment followed by a 10 M NaOH treatment. A crystalline carbon region was also observed when the thermal anneal was omitted. This crystalline region is highly unstable and converts to NCD and carbon onions via electron irradiation in the TEM. X-ray diffraction, Raman, ash content, and temperature-programmed oxidation (TPO) data suggest that tetrahedral amorphous carbon is formed during milling, iron carbides are formed during the thermal anneal step, and both the HCl and NaOH purification steps lead to changes in carbon structure. NaOH oxidizes metal carbides and this process may contribute to NCD formation.
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U2 - 10.1016/j.carbon.2007.04.027
DO - 10.1016/j.carbon.2007.04.027
M3 - Article
AN - SCOPUS:34548458070
VL - 45
SP - 2297
EP - 2306
JO - Carbon
JF - Carbon
SN - 0008-6223
IS - 11
ER -