Abstract:

Alcohol, presented in the hydrolysis of ferric chloride at elevated temperature, inhibits the phase transformation from β-FeOOH to α-Fe_2O_3, reduces the supersaturation of the precipitated species α-F_2O_3, decreases the number of nucleation and therefore favours the formation of much larger uniform α-F_2O_3 particles. With increasing amount of alcohol, the sizes of particles increase, while the shapes of them change gradually from sphere to cube.

Key words: Phase-transformation, Inhibitor, Supersaturation, Nucleation