PLASMA OXIDATION: ACCELERATED THROUGHPUT AND REDUCED ENERGY CONSUMPTION FOR CARBON FIBER CONVERSION PLANTS

The oxidation step of the polyacrylonitrile (PAN) carbon fiber conversion process has traditionally been the bottleneck of the entire process due to the required long processing times – typically 80-120 minutes. Any method of cutting this processing time in half or more would dramatically improve the cost economics of the carbon fiber market. This was the impetus for an investigation that led to the development of an atmospheric pressure plasma-based oxidation process that now has been successfully demonstrated to reduce the oxidation time down to 20-30 minutes. The equipment and process are being scaled to industrial levels, with multiple projects underway to qualify the process for a variety of applications. This paper presents the theory of operation and physics behind the plasma oxidation of carbon fiber precursor. The specific engineering and physics of utilizing atmospheric pressure nonthermal plasma to both generate and deliver highly oxidative chemistry to the fiber (or any other workpiece) is discussed.