RESTRUCTURING OF DISORDERED CARBON MATERIALS BY THERMAL ANNEALING

The aim of the present work is the production of nanocarbons with properties suitable for practical applications starting from sundry kinds of carbon materials restructured in mild conditions (temperature <= 1000 °C). Specifically, carbons employed include cheap materials such as pitches, soot and tarry carbon, produced from high temperature combustion/pyrolytic processes. The thermal annealing has been performed in different operative conditions and the study of the heat-induced structural changes has been accomplished by high level chemical and nanostructural analyses of nanocarbons produced. The array of techniques, specifically developed, includes: size exclusion chromatography and mass spectrometry, thermogravimetry and elemental analysis, UV-Visible absorption, X-Ray diffraction, infrared, fluorescence and Raman spectroscopy. It has been found that part of the loaded carbon material was subjected to evaporation and deposition on the top of the annealing reactor (upper fraction), experiencing a treatment with thermal history in lower temperature range with respect to the part inside the reactor (bottom fraction). A graphitization process at different extent has been found to occur to both upper and bottom fractions of carbon materials in dependence of the chemical composition and structure of the starting material and the experimental conditions employed for the annealing.