INFLUENCE OF TENSION DURING OXIDATIVE STABILIZATION ON SO2 ADSORPTIONCHARACTERISTICS OF POLYACRYLONITRILE (PAN) BASED ACTIVATED CARBON-FIBERS

PAN-based carbon fibers were stabilized under various tensions in the presence of air at 230 degrees C and sequentially activated at 950 deg rees C following carbonization. The prepared carbon fibers were tested for their SO2 adsorption capacity using a thermogravimeter. The magni tude of tension during stabilization and gas environment were varied t o study their effects on SO2 adsorption capacity. It was found that th e tension during the stabilization and the gas atmosphere during activ ation affect the carbon fiber properties, which are closely related to the SO2 adsorption capacity. The influence of stabilization tension a nd activation atmosphere on the SO2 adsorption capacity appear to aris e from their effects on the amount of oxygen functional groups and the surface area of carbon fiber. The highest SO2 adsorption capacity and improved mechanical strength were observed when PAN fibers were activ ated under steam. (C) 1997 Elsevier Science Ltd.