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Enhancement of methanol combustion in a direct injected Diesel engine using catalytically coated glow plugs was examined for platinum and palladium catalysts and compared to a non-catalytic baseline case. Experiments were performed for 6 and 10 brake Kilowatts (bKW) at 2500 rpm. Comparisons were made based on combustion, performance, and emissions including carbon monoxide (CO), oxides of nitrogen (NOx), unburned hydrocarbons (UHC), unburned methanol (UBM), and aldehydes. Results show a decrease in glow plug temperature of 100 K is achievable using platinum catalysts, and 150 K for palladium. Furthermore, the palladium catalyst was found to provide better combustion characteristics than the platinum catalyst. Also, the use of both catalysts produced lower aldehyde emissions, and the palladium reduced NOx emissions as well. However, unburned methanol increased for both catalytic glow plugs with respect to the non-catalytic case.

The effects of platinum and palladium catalysts on the enhancement of methanol combustion were investigated in a high pressure flow reactor and in a single-cylinder, D.I. Diesel engine. Initial studies were carried out in the flow reactor to determine the effect of catalyst temperature and equivalence ratio on the products of methanol combustion. Afterwards, Diesel engine studies were performed with in-cylinder catalysts applied to the exhaust valves in order to maintain high catalyst temperature required for high reactivity. Comparisons were based on performance, combustion characteristics, and emissions. Results of the flow reactor studies show that the catalytic ignition temperature, found to be 570 K, did not vary significantly with equivalence ratio. The Diesel engine experiments revealed that a decrease in glow plug temperature of 400 K was achievable while providing better performance and reduced emissions, including aldehydes, compared to the non-catalytic case.

Proton exchange membrane (PEM) fuel cells are recognized as a good alternative to the internal combustion engine for automotive applications. During the past several years, many companies around the world have investigated this technology as potential solution in terms of efficiency improvements and emission targets for the future. However to be competitive with the internal combustion engine, the fuel cell must withstand the severe conditions imposed by the automotive environment while being economically affordable. At the current time, most original equipment manufacturers (OEM's) are targeting an allowable cost of about 30 $/kW in the 2010 timeframe. In order to help achieve this cost goal, one potential solution is to reduce the number of components in the fuel cell system. Along with reducing cost, the removal of components can lead to a reduction in system complexity and control.

Arthur D. Little in conjunction with the Department of Energy and the Illinois Department of Commerce and Community Affairs are developing an ethanol fuel processor for fuel cell vehicles. Initial studies were carried out on a 25 kWe catalytic partial oxidation (POX) reformer to determine the effect of equivalence ratio, steam to carbon ratio, and residence time on ethanol conversion. Results of the POX experiments show near equilibrium yields of hydrogen and carbon monoxide for an equivalence ratio of 3.0 with a fuel processor efficiency of 80%. The size and weight of the prototype reformer yield power densities of 1.44 l/kW and 1.74 kg/kW at an estimated cost of $20/kW.

Industrial grade ethanol, in concentrations ranging from 130 proof to 200 proof, can be used as a feedstock for a 50kWe advanced fuel processor developed by Arthur D. Little, Inc. for fuel cell vehicles. At 180 proof concentration, hydrated ethanol showed no performance degradation compared with both 200 proof (pure) ethanol and E95 (95% ethanol and 5% gasoline) at equivalence ratios ranging from 3.0 to 4.0. Environmental benefits associated with the use of ethanol in fuel cell power systems include its production from renewable biological sources, low toxicity in the event of an accidental spill, and recycling of carbon dioxide released by the process back to the plant matter used as ethanol feedstock. Cost savings associated with the use of hydrated ethanol are expected to include lower production costs, lower distribution costs, and lower powerplant costs due to the possibility of system simplification.

The feasibility of fuel cell vehicles has now been verified by virtue of recent and ongoing field experience with both hydrogen and reformer based systems. The key issues regarding the timing and extent of fuel cell commercialization are becoming the ability to reduce costs to acceptable levels and the choice of fuel for the power system. The choice of fuel processing technology can dramatically influence the total power system. The design and development of a multi-fuel reformer/fuel cell system for transportation applications has been demonstrated using both software simulations and hardware demonstrations. Feasibility has been demonstrated through six years of prototype hardware and experimental testing culminating with the reformer and CO clean-up device being integrated with a PEM fuel cell. Recent efforts have focused on improving the performance of the various subsystems and increasing the power density and specific power of the integrated fuel processing subsystem.