A 2 kW solar furnace was used to vaporize a graphite target for fullerene synthesis. Tests were performed in a wide range of vaporization rates (0.1–4 g/h), under variable pressure and argon flow rate. Experimental results are interpreted with numerical simulation to define key parameters for large-scale synthesis of fullerenes with solar energy. We demonstrate that the vaporization process is controlled by diffusion in the temperature and pressure ranges 3000–3700 K and 70–250 hPa respectively.
Experimental data and numerical simulation suggest that in the solar reactor, fullerene yield is governed by the dilution of carbon vapor in argon and by the temperature gradient in the cooling zone. Criteria for both parameters are suggested. Consequently, these data, combined with the numerical model accounting for heat, mass and fluid flow inside the reactor, may be used for the design of large-scale solar process.