Influence of activation temperature on surface and adsorption properties of PAN-based activated carbon fibers/phenolic resin matrix composites

PAN-based activated carbon fibers/phenolic resin matrix composites (ACFCs) were manufactured via molding process with oxidized carbon fabrics (plain-type) and phenolic resin (resole-type) compounded by 70: 30 wt%. The green body (as molded) was submitted to carbonization (at 1000 °C) in an inert environment and activation (at 700, 800, 900 and 1000 °C) in a CO² environment. In this work, the influence of activation temperatures was investigated in surface properties, such as pH, acid- and base-values by titration method, and in adsorption properties, i.e., specific surface area and pore structures by BET-method of the composites. Also, the pressure drops of the specimens were calibrated by ASTM. As a result, the activation temperature influenced the surface property of ACFCs. When the activation temperature was higher than 900 °C, the surface was gradually developed in basic nature. And, the evolutions of specific surface area, total pore volume and pore size distribution of ACFCs could be easily confirmed the dependence on the activation temperature. Among them, well-developed pore structure from adsorption characteristics was changed of the ACFCs activated at 900 °C. Also, the pressure drop was slightly decreased with increasing the temperature due to increasing the burn-off with heat treatment temperature of ACFCs.