Influence of tension during oxidative stabilization on SO2 adsorption characteristics 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 degrees C following carbonization. The prepared carbon fibers were tested for their SO2 adsorption capacity using a thermogravimeter. The magnitude of tension during stabilization and gas environment were varied to study their effects on SO2 adsorption capacity. It was found that the tension during the stabilization and the gas atmosphere during activation affect the carbon fiber properties, which are closely related to the SO2 adsorption capacity. The influence of stabilization tension and activation atmosphere on the SO2 adsorption capacity appear to arise 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 activated under steam. (C) 1997 Elsevier Science Ltd.