International Journal of Hydrogen Energy, Vol.36, No.1, 421-431, 2011
Interaction between a bimetallic Ni-Co catalyst and micrometer-sized CaO for enhanced H-2 production during cellulose decomposition
An SBA-15 supported Ni-Co catalyst and micrometer-sized CaO were used as additives in cellulose decomposition in the presence and absence of injected H2O. A thermogravimetric analyser coupled to a mass spectrometer (TG-MS) was used to examine the different roles of the Ni-Co catalyst and CaO in tuning the kinetics of decomposition and the distribution of the gaseous products. There existed optimal additive/cellulose ratios beyond which H-2 generation could not be enhanced by using more of a single additive. However, the combination of both the additives dramatically promoted selective H-2 generation. The mechanism of their interaction is discussed. When the catalyst, CaO, and 1 vol.% H2O were present, a stable sustained (interval of > 150 degrees C) high-rate (max > 80 vol.%) H-2 output resulted. The cumulative H-2 yield (250-550 degrees C) reached 688 ml/g cellulose and the H-2 selectivity during this period was nearly 70 vol.%. The char yield was also minimized, at 5.2%. (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.