AN EVALUATION OF THE DIFFERENTIAL PARTITIONING AND SEPARATION OF C-60 AND C-70 FULLERENES IN A BIPHASIC SYSTEM USING CENTRIFUGAL PARTITION CHROMATOGRAPHY (CPC)

摘要

The partition coefficients of C-60 and C-70 fullerenes were measured in several different organic, 2-phase (liquid-liquid) systems using centrifugal partition chromatography (CPC). The partition coefficients of C-60 and C-70 were sufficiently different in some biphasic solvent systems to provide a CPC separation of these fullerenes. A phase diagram was made of the best 2-phase system for fractionating C-60 and C-70 fullerenes. This system contained the solvents 1,2-dichlorobenzene, isooctane, and dimethylformamide (DMF). The separation times, selectivity, and efficiency are affected by the ratios of the major solvent components, the addition of small amounts of a quaternary solvent, and the temperature (in addition to the usual instrumental parameters). Preparative separations of fullerenes were done and a maximum batch production was calculated for one solvent system. It appears that a significantly greater amount of fullerenes can be purified per run in this system than in corresponding HPLC systems. The rather unusual organic biphasic solvent systems developed for the fractionation of fullerenes may be useful for future separation and purification of more conventional organic compounds.