Dye Adsorption on Mesoporous Activated Carbon Fiber Obtained from Pitc Containing Yttrium Complex and tha Acid Treatment Effects

Abstract

The adsorption isotherms of various acid, direct, and basic dyes on mesoporous activated carbon fibers (Y-ACF) obtained from pitch containing Y (acac) ₃ were measured and the influence of their acid treatment was examined. TheY-ACF highly adsorbed dyes with large molecular size, whereas microporous activated carbon fiber scarcely adsorbedthese dyes. Electron probe X-ray microanalysis indicated that yttrium oxide in Y-ACF, which was produced from theyttrium complex, was thoroughly eluted by acid treatment of Y-ACF. The adsorption amounts of acid and direct dyeswith large molecular size on Y-ACF decreased by acid treatment. On the other hand, the adsorbed amount of basic dye increased by acid treatment. The adsorption characteristics was associated with the electrostatic properties of theactivated carbon fibers.