Patent ID: 7351390
Filing Date: 2008-04-01
Classification: D01F

Abstract:
1. A method for continuously purifying a carbon fiber body by heat treating the carbon fiber body to remove sodium contained in carbon fibers, the method comprising the steps of: placing the carbon fiber body to be treated in an oven having a gas inlet and an effluent gas outlet connected to an exhaust pipe; heating the carbon fiber body in the oven at a temperature at which sodium contained in the carbon fibers is sublimed, under an atmosphere of inert gas supplied through the gas inlet; continuously extracting a gaseous effluent containing said inert gas and sodium in sublimed form from the oven through the effluent gas outlet and via the exhaust pipe, while maintaining within the oven a pressure lower than atmospheric pressure, and injecting at least one sodium-neutralizing agent continuously into the gaseous effluent extracted from the oven during heat treatment at a location immediately downstream from the gas effluent outlet while maintaining any sodium contained in the gaseous effluent in sublimed form at the location of injection.