The effect of Al addition on the prevention of Ni sintering in bio-ethanol steam reforming for molten carbonate fuel cells

This paper investigates the effect of modifying an Ni catalyst on the prevention of sintering of the catalyst at high temperatures, without causing a reduction in catalytic activity. The Ni catalyst was modified by adding Al through a solid-gas-solid reaction at a low temperature to produce an Ni-Al solid solution. This process allows for low-cost production of the modified catalyst. An activity test of the catalysts was carried out at 650 °C and 1 atm to simulate direct internal reforming of a molten carbonate fuel cell (MCFC). Experimental results showed consistent activity of the Al-modified catalyst, even after aging under severe conditions (900 °C) to simulate accelerated sintering. TEM data did not show any significant physical changes even after aging. Addition of Al appeared to have successfully prevented Ni from sintering without reducing its catalytic activity in reforming bio-ethanol. In addition, an Ni-Al/MgO catalyst, integrated into the anode of an MCFC, was successfully tested for over 2000 h without any significant performance degradation.