Effect of hydrogen on the mesopore development of pitch-based spherical activated carbon containing iron during activation by steam

In the present paper, pitch-based spherical activated carbon (PSAC) was act ivated by steam under various carrier gases such as nitrogen, mixture of ni trogen and hydrogen (H-2/N-2: 1/3 mol/mol) and pure hydrogen. The results s howed that hydrogen inhibited the uncatalyzed C-H2O reaction while accelera ted the iron-catalyzed one. Furthermore, the effects of hydrogen became muc h more remarkable as the proportion of hydrogen increased. In this case, th e ratio of mesopore volume of the resultant PSAC increased, but the micropo re volume and micropore surface area decreased remarkably. The ratio of mes opore could reach more than 90%, and the mesopore mainly distributed at 10- 50 nm. Thus, the PSAC with higher ratio of mesopore can be prepared by the aid of hydrogen as well as iron. (C) 1999 Elsevier Science Ltd. All rights reserved.