FULLERENES FROM BROWN (LIGNITE) COAL

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% yield from charred Loy Yang coal. Charred calcium exchanged Loy Yang coal and lanthanum exchanged humic acid extracted from Bacchus Marsh coal were also studied. The purpose was to investigate the possibility of entrapping the exchanged metals in fullerenes and to determine the effect 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 formation of fullerenes. Charred acid-exchanged Loy Yang coal was also studied 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%).