A novel CO₂ utilization technology for the synergistic co-production of multi-walled carbon nanotubes and syngas

Dry reforming of methane (DRM) is a well-known process in which CH₄ and CO₂ catalytically react to produce syngas. Solid carbon is a well-known byproduct of the DRM but is undesirable as it leads to catalyst deactivation. However, converting CO₂ and CH₄ into solid carbon serves as a promising carbon capture and sequestration technique that has been demonstrated in this study by two patented processes. In the first process, known as CARGEN technology (CARbon GENerator), a novel concept of two reactors in series is developed that separately convert the greenhouse gases (GHGs) into multi-walled carbon nanotubes (MWCNTs) and syngas. CARGEN enables at least a 50% reduction in energy requirement with at least 65% CO₂ conversion compared to the DRM process. The second process presents an alternative pathway for the regeneration/reactivation of the spent DRM/CARGEN catalyst using CO₂. Provided herein is the first report on an experimental demonstration of a 'switching' technology in which CO₂ is utilized in both the operation and the regeneration cycles and thus, finally contributing to the overall goal of CO₂ fixation. The following studies support all the results in this work: physisorption, chemisorption, XRD, XPS, SEM, TEM, TGA, ICP, and Raman analysis.