Preparation of carbon fibers from liquefied wood

Carbon fibers are prepared from liquefied wood by adding hexamethylenetetramine and soaking in a solution containing hydrochloric acid and formaldehyde as main components. Structure evolution of carbon fibers from liquefied wood (LWCFs) is investigated by using FTIR and XRD. The results show that the structure of the precursor fibers from liquefied wood has been completely changed after carbonization. The apparent crystallite size (L _c(002)) and the apparent layer-plane length parallel to the fiber axis (L _a(100)) gradually increase during carbonization. Carbon fibers with the maximum tensile strength of 1.7 GPa are obtained under certain carbonization conditions. At the same time, it is also found that 600–800°C is the critical stage at which the specific surface area of LWCFs changes.