NANOSYSTEMS: PHYSICS, CHEMISTRY, MATHEMATICS, 2013, 4 (3), P. 344–351
PRE-CHROMATOGRAPHY CRUDE SEPARATION OF LIGHT FULLERENES BY POLY-TERMICAL (RE)CRYSTALLIZATION METHOD
V. A. Keskinov – Saint-Petersburg State Technological Institute (Technological University), Saint Petersburg, Russia; ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia; keskinov@mail.ru
N.A. Charykov – ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia; Saint-Petersburg State Technological Institute (Technological University), Saint Petersburg, Russia
M.V. Keskinova – ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia
Yu.V. Murashkin – Saint-Petersburg State Technological Institute (Technological University), Saint Petersburg, Russia; ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia; keskinov@mail.ru
A. A. Blokhin – Saint-Petersburg State Technological Institute (Technological University), Saint Petersburg, Russia; ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia; keskinov@mail.ru
K.N. Semenov – Saint Petersburg State University, Saint Petersburg, Russia; ILIP Ltd. (Innovations of Leningrad Universities and Enterprises), Saint Petersburg, Russia
The pre-chromatography method of crude separation of light fullerenes (C60 and C70) 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 °C) and crystallization of solid solutions from saturated liquid solutions at low temperature (–20 °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 C60 fullerene and the second, considerably enriched by the C70 fullerene. In this separation process, the concentrate enriched by C60, is also enriched in C84. In that process, 98.6 mass % of C60 was contained in the C60-enriched concentrate (from the sum content of C60 in the initial extract), simultaneously, 65.9 mass % of C70 contained in the C70-enriched concentrate (from the sum content of C70 in the initial extract).
Keywords: light fullerenes, heavy fullerenes, o-xylene, separation, solution, (re)crystallization, temperature, counter-current, pre-chromatography, high efficiency.
PACS 61.48.+c