Plasma-assisted production of carbon black and carbon nanotubes from methane by thermal plasma reform

Abstract

Thermal plasma processing of carbon sources using a plasma jet with high heat capacity is one of the most promising methods for the synthesis of new materials. A method for obtaining carbon black (CB) and carbon nanotubes (CNT) through the pyrolysis of methane using a thermal plasma direct current (DC) system is reported herein. The cracking operation is performed in the absence of oxygen using an external power source, i.e., a plasma jet generated by an argon plasma torch. The obtained carbonaceous materials were characterized by Raman spectroscopy, scanning, and transmission electron microscopy. The results showed that CNT are produced in the presence of a catalyst while CB formation occurs without a catalyst. The Raman ID/IG ratio indicated that the sample obtained using a 5%Ni/Al2O3 catalyst contains a higher quantity of pure CNT than the other catalysts tested (10%Ni/Al 2O3 and 10%Ni-5%Ce/Al2O3). © 2014 Sociedade Brasileira de Química.