HIGH-PURITY VAPOR-PHASE PURIFICATION OF C-60

A method is described which utilizes the difference in vapor pressure between C60 and heavier fullerenes to produce ultrahigh purity C60. Fu llerene extract is introduced into one end of a distillation column wi th a series of evenly spaced perforated baffles inside. The extract is heated to 970 K under high vacuum, and a linear temperature gradient is established along the column. As the mixed fullerene vapor effuses down the column, it becomes enriched in the more volatile species. C60 with a purity of 99.97% has been obtained. This method shows promise in the purification of more exotic fullerene compounds.