Carbon black processing by thermal plasma. Analysis of the particle formation mechanism

An original plasma process for carbon black and hydrogen synthesis is prese nted. A pilot scale (100 kW) reactor is developed to obtain new carbon blac k grades from hydrocarbon cracking. Even if three populations of particles are observed, the plasma carbon black is mainly characterised by spherical nanoparticles with a high degree of turbostratic organisation. A particle f ormation mechanism is proposed on the basis of a multiscale analysis of the plasma reactor accounting for: heat and mass balance, RTD measurement and internal flow modelling and particle characterisation by TEM. The mechanism is characterised by two steps: first, a low temperature particle growth an d second, a high temperature annealing. As a result, particle structure is strongly related to internal mixing phenomena. (C) 2001 Elsevier Science Lt d. All rights reserved.