Industrial & Engineering Chemistry Research, Vol.56, No.21, 6213-6220, 2017
Nanostructured Carbon Xerogels by Super-Fast Carbonization
Traditional synthesis methods of highly porous carbon [GRAPHIC] xerogels impose many limitations on production in large scale such as low heat and mass transfer and long processing time. In this study, for the first time, recorsinol formaldehyde (RF) xerogels were carbonized by fast heating rates (sigma) in a fluidized bed reactor. The specific surface area (Phi) and pore volume of carbon xerogels were examined in terms of particle size (approximate to 100 and 297 mu m), carbonization temperature (298-1273 K), and sigma (5-50 K min(-1)): The temperature above which Phi. decreases by increasing temperature was shifted to lower values for larger particles. Moreover, Phi and volume of micro- and mesopores increased by increasing sigma. Possible mechanisms to interpret the effects of carbonization temperature and sigma on physical properties of carbon xerogels were finally furnished. Carbonization time was found to be approximate to 25-times faster by fluidization while maintaining the quality of xerogels.