Caustic leaching of fine particles of Fe2Al5 alloy to produce skeletal Fe catalysts was studied using a 24 factorial experimental design, in which alloy particle size, aqueous NaOH concentration, temperature and stirrer speed were varied. Analysis of the results from the design showed that the BET surface area of the skeletal iron increased with decreases in temperature, caustic concentration and particle size according to SBET = 222.7 − 0.461 · T − 2.35 · cNaOH − 0.0245 · D p. An Avrami–Erofeev model −ln(1 − α) = kt with an activation energy of 55 ± 5 kJ mol−1 and a shrinking core model for volume contraction 1 − (1 − α)1/3 = kt and an activation energy of 56 ± 5 kJ mol−1 provided the best fit to the kinetic data for leaching.