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Stepwise chlorination–chemical vapor transport (SC–CVT) reaction has been investigated for the rare earth oxide mixtures Gd2O3–Tb4O7, Tb4O7–Dy2O3 and Dy2O3–Ho2O3 mediated by vapor complexes LnAlnCl3n+3 (where Ln=rare earth elements). The results show selective deposition of lighter elements at higher temperatures. The separation factors are 5.84 for Gd/Tb, 3.72 for Tb/Dy and 3.13 for Ho/Dy when using CO as the CVT carrier gas. A combination of enhanced separation factor with reduced total transport yield is also observed for the Tb4O7–Dy2O3 system when using argon as the CVT carrier gas. [Copyright &y& Elsevier]