EXFOLIATION AND TEXTURAL MODIFICATION OF ANTHRACITES

Two anthracites (La Mure, France and Hongay, Vietnam) have been exfoli ated after intercalation in a perchloric and nitric acid solution foll owed by a thermal shock treatment. The anthracites are extensively exf oliated as shown by scanning electron microscopy, and this treatment i s responsible for a significant development of mesoporosity and a grea t increase of specific surface area. Hongay anthracite was then steam activated, and specific surface areas of 1200 m(2)/g have been obtaine d with a well developed mesoporous texture. Moreover, after exfoliatio n, the anthracite reactivity with water vapour during steam activation is increased by a factor of 3. This shows that anthracites may be an important source of raw materials for the production of active carbons with a large pore size distribution. Copyright (C) 1996 Elsevier Scie nce Ltd.