Continuous polyethylene pyrolysis for hybrid flame/CVD synthesis of carbon nanotubes.

摘要

A system was designed to integrate the continuous feeding of polyethylene for pyrolysis into the hybrid flame/CVD carbon nanotube (CNT) synthesis process previously developed in this laboratory. Following the completion of the stainless steel design and machining operations, the polyethylene dispenser, screw conveyor, pyrolysis chamber, venturi flame holder, particle filter, synthesis chamber and dual]zone heating system were successfully integrated for full operation. A water cooling unit was incorporated with the screw conveyor to ensure flawless delivery of polyethylene to the pyrolysis chamber, as well as a support system to suspend the CNT catalyst within the synthesis chamber. As with the previously developed process, the intended use of combustion effluent within the apparatus was to synthesize multi]walled CNTs using stainless steel wire mesh. This was facilitated by an extensive study of the effluent produced with this continuous feeding system at varying system settings and in comparison to the previous apparatus, followed by a determination of the system parameters, which result in conditions most favorable to multi walled CNT growth.