Meso?Macro porous alumina was fabricated using yeast cells as a pore?forming
agent. Alumina powder synthesis was achieved by a low cost process (recrystallisation
of alum).The effect of the pore forming agent on the true porosity, bulk density
and thermal conductivity of porous alumina was characterized. The results show
that the true porosity increased with the increasing addition of yeast cells. The bulk
density and thermal conductivity at room temperature decreased with the increasing
yeast addition. A genetic algorithm method was used to minimize the thermal conductivity
of the macro?porous alumina based on the amount of yeast cells used, the
sintering temperature, and the hold time. The genetic algorithm found that the best
thermal conductivity achievable was equal to 0.152 Watt/m. °C at 20wt% concentration
of yeast, a sintering temperature of 1230°C and 1.5 hours of soaking time. The
experimental value was 0.14 Watt/m. °C and the slight variance between these values
were postulated to be due to experimental error in the measurements.