Boreskov Institute of Catalysis SB RAS, Novosibirsk, Russia

OP-3-6H 2 PRODUCTION BY STEAM REFORMING OF BIOETHANOLIlenia Rossetti, Cesare Biffi, Gian Franco Tantardini, Lucio ForniDip. Chimica Fisica ed Elettrochimica, Università degli Studi di Milano, v. C.Golgi 19,I-20133 Milano, Italy. Fax: +39-02-50314300, e-mail: ilenia.rossetti@unimi.itNi-based catalysts have been produced by flame pyrolysis (FP) and tested for thesteam reforming (SR) of ethanol. The catalysts have been supported on Al 2 O 3 (forcomparison with commercial samples), TiO 2 and La 2 O 3 , with metal loading between5 and 15 wt%. Two sets of samples have been prepared: the former by impregnationof a Ni precursor on the FP-prepared support, the latter by direct FP synthesis. Thecatalysts were characterised by XRD, N 2 adsorption-desorption, TPD-TPR-TPO,SEM. The activity tests were performed at atmospheric pressure and at threedifferent temperatures (500-750°C) in a continuous tubular reactor on 0.5 g ofcatalyst, pre-activated at 800°C in H 2 flow. Water and ethanol have been fed in 3:1molar ratio, with variable VHSV. Data have been collected for up to 100 h on-streamon each sample, to check for catalyst deactivation.The FP synthesis led to nanosize particles (20-60 nm), characterised by suitablethermal resistance for this high temperature process. Independently of thepreparation route, all the samples showed higher reducibility with respect to literaturedata. The activity tests showed full ethanol conversion at 750°C, with carbon balanceclosing to ±6 mol%. H 2 molar fraction in the products was usually higher than 0.70,whereas CO and CO 2 were strongly dependent on the operating conditions andcatalyst formulation. At low temperature a contribution of the water gas shift reactionis indeed expected, increasing H 2 yield and lowering CO concentration in the outletgas. This is especially desired for two reasons. On one hand, a low operatingtemperature decreases the thermal input to the process. On the other hand, if H 2 is tobe fed to fuel cells, careful purification from CO is required, particularly if a PEM-FCis used, so that the lowering as much as possible the CO concentration in thereformate gas is welcome.Some undesirable by-products such as acetaldehyde and methane wereobserved occasionally at low temperature only and their concentration was virtuallyabsent when increasing contact time. By increasing again reaction temperature a fullrecovery of activity and optimal carbon balance were always obtained.74