REGENERATION STRATEGIES OF DEACTIVATED CATALYSTS FOR THERMO-CATALYTIC DECOMPOSITION PROCESS IN A FLUIDIZED BED REACTOR P. Ammendola 1 , R. Chirone 1 , G. Ruoppolo 1 , and G. Russo 2 1 Istituto di Ricerche sulla Combustione – CNR, Napoli, Italy 2 Dipartimento di Ingegneria Chimica, Universita ` degli Studi di Napoli Federico II, Napoli, Italy The present article addresses on the possibility of carrying out a two-stage operation for hydrogen production from methane Thermo-Catalytic Decomposition (TCD) in a fluidized bed, consisting into first operating the reactor for methane decomposition, until a defined catalyst deactivation degree is approached, and then operating the fluidized bed as a com- bustor or a gasifyer for catalyst regeneration by carbon removal. Three different strategies of catalyst regeneration, carbon combustion in air, CO 2 gasification and steam gasification, have been analyzed. The regeneration strategies have been compared on the basis of the efficiency of carbon removal and the performances of regenerated catalyst with respect to the TCD process. The effect of multiple cycles of decomposition and regeneration steps has been also quantified. A reasonable cyclic process has been simulated switching between two different feeds, the first containing CH 4 and the second containing air. The effect of different air regeneration times on the product distribution in the CH 4 decomposition phase has been tested to individuate its optimal value. Keywords: Carbon combustion; Carbon gasification; Catalyst regeneration; Fluidized bed; Methane thermo-catalytic decomposition INTRODUCTION The Thermo-Catalytic Decomposition (TCD) of methane is an attractive and promising process towards the production of hydrogen with reduced CO 2 emissions (Muradov et al., 2006; Muradov and Vezirog ˘lu, 2005) and it could be an important step towards the realization of more effective and environmental friendly processes for hydrogen production. In this framework, fluidized bed reactors have been recently proposed (Muradov et al., 2005, Lee et al., 2004, Dunker et al., 2006) as a useful alter- native solution to fixed bed reactors to operate with lower pressure drops, to optimize the energy balance due to the relatively high efficiency in heat transfer mechanism and to make possible a continuous production of hydrogen as a result of a continuous catalyst regeneration due to deposited carbon attrition (Ammendola et al., 2006). The consideration of carbon attrition as a favourable mechanism during TCD process is a peculiar aspect being attrition phenomena commonly considered a Address correspondence to G. Ruoppolo, Istituto di Ricerche sulla Combustione, CNR, P. Le Tecchio 80, 80125 Napoli, Italy. E-mail: ruoppolo@irc.cnr.it 869 Combust. Sci. and Tech., 180: 869–882, 2008 Copyright # Taylor & Francis Group, LLC ISSN: 0010-2202 print/1563-521X online DOI: 10.1080/00102200801894174