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

V. A. Keskinov ; N. A. Charykov ; M. V. Keskinova ; Yu. V. Murashkin ; A. A. Blokhin ; K. N. Semenov

Nanosistemy: fizika, himiâ, matematika, Tome 4 (2013) no. 3, pp. 344-351

Résumé

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).

Détail

Keywords: light fullerenes, heavy fullerenes, o-xylene, separation, (re)crystallization, temperature, counter-current, pre-chromatography, high efficiency.
Mots-clés : solution