Porosity Evolution of Activated Carbon Fiber Prepared from Liquefied Wood. Part II: Water Steam Activation from 850 to 950 °C

To acquire activated carbon fiber from phenol-liquefied wood (PLWACF) with better developed pore structure and a high proportion of mesoporosity, the porosity evolution of PLWACF activated at temperatures from 850 to 950 degrees C by water steam was detected by the physical adsorption of N-2 at -196 degrees C. Results showed that the pore structure was well developed by prolonging the activation time at 850 to 910 degrees C, and it was easy to obtain PLWACF having exceptionally high surface area (larger than 2560 m(2) g(-1)). However, PLWACF with a specific surface area larger than 3000 m(2) g(-1) could only be obtained in the late activation stages from 850 to 880 degrees C. Using this activation process, the mesoporosity was remarkably developed. The mesopore proportion drastically increased with an increase in activation temperature or time, reaching a maximum of 49.5%. The pore size distribution widened as the activation time increased and appeared to accelerate with the use of a higher activation temperature. The mesopore size distribution was enlarged from 2.8 to 5.8 nm.