Direct glycerol fuel cell

Direct Glycerol Fuel Cell State-of-Art, Challenges and Patents... 

In direct glycerol fuel cells, the fuel and the oxidant used are glycerol (from biodiesel fabrication, for example) and oxygen from the air, respectively. In such fuel cells, the complete reaction taking place at the anode and cathode are represented by the equations ... 

Fig. 4.5 Representation of a direct glycerol fuel cell for generation of clean electric eneigy and co-generation of heat and commercially interesting chemicals, such as propanediol, ethylene...

Direct Glycerol Fuel Cells Comparison with Hydrogen and Direct Ethanol Fuel Cells... 

From a perasal of Fig. 24, it is apparent that the Pd/MWCNT anode is particularly suitable for the oxidation of ethanol which shows the highest open circuit voltage (OCV, 0.74 V) and peak power density (18.4 mW cm at 0.2 V) out of the three fuels investigated. Notably, the performance trend in the passive DAFC is different from that observed in the half cell where glycerol provides the highest peak current density (Fig. 13). On the other hand, the lower performance of both the direct methanol fuel cell (DMFC) and the direct glycerol fuel cell (DGFC) as compared to the DEFC is in line with the chronopotentiometric experiments illustrated in Fig. 13. 

In fuel cells working with a liquid fuel, usually an alcohol such as methanol (a direct methanol fuel cell - DMFC), ethanol (a direct ethanol fuel cell - DEFC), glycerol (a direct glycerol fuel cell - DGEC), etc., in addition to the necessity to activate the ORR at the cathode, the alcohol oxidation reaction at the anode also involves a high overpotential. This high overpotential is mainly due to the formation, after dissociative adsorption of the alcohol at the catalyst surface, of poisoning species which block the catalytic surface the main one adsorbed is carbon monoxide. ... 

Fuels cells are of interest both from energetic and environmental considerations. When methanol is fed directly to an anode, as in Direct Methanol Fuel Cells , electric power is generated, making the devices suitable for small and lightweight uses [53], Alternative fuels such as polyhydric alcohols like ethylene glycol and glycerol are much less volatile and toxic, on the one hand, and electrochemically oxidizable on the other [54]. Therefore, the electrochemical oxidation of various polyhydric alcohols has been investigated in acidic as well as in alkaline conditions. 

The dilution of Pd with non-noble metals in a smart catalytic architecture capable of rapidly and stably oxidizing alcohols on anode electrodes would knock down the main barriers to the commercialization of direct alcohol fuel cells (DAFC), especially those fed with primary alcohols, hi er than methanol, and polyalcohols. Indeed, apart from methanol for which there exist platinnm based catalysts capable of prodncing cnrrent densities of several tens of mW cm, the higher alcohols like ethanol and polyalcohols like glycerol are difficnlt to oxidize on platinum or platinum alloyed with either noble or non-noble metals. 

Matsuoka et al. [8] tested ADAFCs formed by Pt-Ru/C as anode catalyst, Pt/C or Ag/C as cathode catalyst, and the AHA membrane by Tokuyama Co. The cells operated at 50 °C and were fuelled with four polyhydric alcohols and methanol for comparison. These alcohols (1 M) were dissolved in 1 M KOH aqueous solution. The maximum power densities were in the order of ethylene glycol > glycerol > methanol > erythritol > xylitol. The direct ethylene glycol fuel cell showed the highest power density. AlkaUne direct alcohol fuel cells using silver as a cathode catalyst showed good performance however, the open-circuit voltage of a cell with... 

Bambagioni V, Bianchini C, Marchionni A, Filippi J, Vizza F, Teddy J, Serp P, Zhiani M (2009) Pd and Pt-Ru anode electrocatalysts supported on multi-walled carbon nanotubes and their use in passive and active direct alcohol fuel cells with an anion-exchange membrane (alcohol = methanol, ethanol, glycerol). J Power Sources 190(2) 241-251... 

Bambagioni, V, Bianchini, C., Marchionni, A., et al. (1990). Pd and Pt-Ru Anode Electrocatalysts Supported on Multi-waUed Carbon Nanotubes and their Use in Passive and Active Direct Alcohol Fuel Cells with an Anion-exchange Membrane (Alcohol = Methanol, Ethanol, Glycerol), J. Power Sources, 190, pp. 241-251. 

Anode Catalysts for Direct Polyol Fuel Cells (Ethylene Glycol, Glycerol) Cogenerate Electricity 179... 

The growth of interest in DMFC and DEFC seems to have reached a steady state during the last years with almost a factor 5 more works on methanol respect to ethanol. It can be also observed an incipient interest for ethylene glycol and propanol as a direct fuel in PEM fuel cell since 2000, and a small but raising number of studies exploring glycerol as a new liquid fuel since 5 years ago. 

Hie A, Simoes M, Baranton S, Coutanceau C, Martemianov S (2011) Influence of operational parameters and of catalytic materials on electrical performance of direct glycerol solid alkaline membrane fuel cells. J Power Sources 196 4965-4971... 

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