The electrical arc in helium of charred Victorian brown coals from the
Bacchus Marsh, Yallourn, Loy Yang and Morwell mines was studied. Each
char produced fullerenes in 1.9-2.5% yields, except for the 7.7% yiel
d from charred Loy Yang coal. Charred calcium exchanged Loy Yang coal
and lanthanum exchanged humic acid extracted from Bacchus Marsh coal w
ere also studied. The purpose was to investigate the possibility of en
trapping the exchanged metals in fullerenes and to determine the effec
t of these exchanged ions on fullerene yields. Infrared data show that
little or no C60 or C70 fullerenes were produced, nor were there any
metal entrapped fullerenes. Thus, exchanged metal ions suppress the fo
rmation of fullerenes. Charred acid-exchanged Loy Yang coal was also s
tudied with the expectation of producing a higher fullerene yield than
the raw coal after removal of metal cations. Fullerenes were produced
in good yield (4.5%) although significantly lower than the raw coal (
7.7%).