Pre-chromatography crude separation of light fullerenes by poly-termical (re)crystallization method

The pre-chromatography method of crude separation of light fullerenes (C$_{60}$ and C$_{70}$) is based on multistage processes of (re)crystallization – the solution of fullerenes solid solutions in liquid solvent (o-xylene) or in liquid o-xylene solutions at high temperature (85$^\circ$C) and crystallization of solid solutions from saturated liquid solutions at low temperature (–20$^\circ$C). As a result, for example, the initial standard fullerene extract may be efficiently divided into two different solid solutions — the first, considerably enriched in C$_{60}$ fullerene and the second, considerably enriched by the C$_{70}$ fullerene. In this separation process, the concentrate enriched by C$_{60}$, is also enriched in C$_{84}$. In that process, 98.6 mass % of C$_{60}$ was contained in the C$_{60}$-enriched concentrate (from the sum content of C$_{60}$ in the initial extract), simultaneously, 65.9 mass % of C$_{70}$ contained in the C$_{70}$-enriched concentrate (from the sum content of C$_{70}$ in the initial extract).