Thermal and structure analysis on reaction mechanisms during the preparation of activated carbon fibers by KOH activation from liquefied wood-based fibers

In this study, wood-based fibers were used as raw materials to prepare activated carbon fibers (ACFs) by carbonization at 500 degrees C followed KOH activation at 850 degrees C process. The structure of the fibers was characterized by Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analyses. Besides, the volatiles of the final products were determined by thermogravimetry-mass spectrometry (TG-MS) and titration. The reaction mechanisms were consequently deduced. In the first carbonization process, it was mainly related to substitution, scission, and oxidization reactions of methylene. And in the second activation process, KOH and carbon began to react at 530 degrees C, resulting in potassium compounds, which further reacted with carbon. Meanwhile, temperature elevation caused polycyclic reactions, which made the ACFs a graphite-like microcrystalite structure. (C) 2015 Elsevier B.V. All rights reserved.