Characterization of Carbonaceous Gel and Gel Beads

Abstract

Carbonaceous gel was prepared from the alkaline solution dissolving amphiphilic carbonaceous material. Gelation of the amphiphilic carbonaceous materials dependedon concentration of the amphipihlic carbonaceous material and the alkaline solution. This so-called carbonaceous gel showed a reversible transformation between sol and gel with temperature. That is, this gel has a quasi-stable structure like agar.Moreover, a carbonaceous dry gel was prepared by drying the carbonaceous gel. This carbonaceous dry gel gave a different thermal behavior from that of the original amphiphilic carbonaceous material.Carbonaceous gel beads were prepared by a new method termed “water in oil emulsion method” using the alkaline aqueous solutions dissolving the amphiphilic carbonaceous materials. These beads had spherical shape and smooth surface. However, the surface morphology and area of the beads were changed by heat-treatment. Especially, by heat-treatment at 900°C the gel beads prepared from aqueous solution of potassium hydroxide became rough surface and had over 400 times larger surface area than as-prepared.