The production of chemically-activated carbon

In an attempt to optimise the microporosity in an activated carbon, controlled heating of sucrose chars and other precursor materials was carried out in an inert environment with an excess of potassium or sodium hydroxide. Initially, the precursor materials were subjected to a regulated temperature time profile to elevated temperatures (400-900 degrees C) and subsequently cooled. The products were then exposed either to an atmosphere of methanol vapour or to the air. Micropore volumes exceeding 1.0 mL g(-1) were obtained at temperatures between 750 and 800 degrees C for carbons that were produced from sucrose, High yields of good microporous activated carbons were made at activation temperatures as low as 540 degrees C. Other precursor materials were also tested for their ability to yield microporous carbon by potassium hydroxide activation. These included coffee ground carbon, macadamia nut shell carbon and various polymer carbons such as polyvinylidene chloride (Saran A homopolymer) carbon, and furan-based polymer carbons. (C) 1999 Elsevier Science Ltd. All rights reserved.