Viscose‐based porous carbon fibers: improving yield and porosity through optimization of the carbonization process by design of experiment

In this study, the production of porous carbon fibers from viscose fibers was investigated. The effects of final carbonization temperature (600–1000 °C) and heating rate (6–600 °C h−1), which determine the carbonization process, on carbon yield, and specific surface area were investigated using a central composite design. The statistical models found were then used to optimize both the yield and the porosity of the carbonized fibers, which are the most important factors for further use as precursors for activated carbon fibers. Despite the contrary effects, porous carbon fibers with a yield of 21.2% could be produced, which at the same time have a specific surface area of 175 m2 g−1. The fibers produced were also characterized by SEM, FTIR and Raman spectroscopy, XRD and CHNS analysis.