1994 Volume 1994 Issue 164 Pages 199-205
Activated carbon fiber (ACF) is used as an adsorbent for water purification, and the application field and the amount will be expanded by improving the property. So, we tried to make the surface of ACF hydrophobic by heat-treating in hydrogen flow (H2) up to 1000°C and by treating with low temperature plasma of carbon tetra fluoride (CF4). And from the view point of keeping good handling quality of ACF, the change of its mechanical properties, due to surface treatment, such as tensile strength, was investigated in this paper.
Followings are the results: (1) By heat treatment in H2 flow, weight of ACF decreased, while there were both cases where the diameter decreased and where the diameter did not change. It depended on the kind of ACF.(2) Tensile strength of heat-treated ACF became higher and had maximum point between 500 and 750°C of heat treatment temperature. The temperature for the peak point depended on the kind of original fibers.(3) By the heat treatment at 900°C in H2 flow, decrease in containing oxygen groups on the surface was confirmed from the ESCA results. It was also confirmed from the measurement of equilibrium adsorbed water that the surface of ACF was made hydrophobic.(4) By CF4 plasma treatment, the mechanical properties and the equilibrium adsorbed water of ACF were not changed substantially.
