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A mesoporous boehmite (γ-AlOOH) synthesis and vanadate (V(V)) ion adsorption and desorption on the mesoporous γ-AlOOH were investigated. The synthesis and adsorption studies showed that the mesoporous γ-AlOOH with a BET surface of 442 m2 g-1 and a pore size of 2.75 nm possessed a maximum V(V) ion adsorption capacity of 3.28 mmol g-1. The adsorption mechanism results showed that the mesoporous γ-AlOOH liberated surface hydroxyls to form coordinatively unsaturated AlVI centres to adsorb V(V) ions which connected oxygen of the coordinatively unsaturated AlVI centres with mono-oxo, VvO terminal double bonds. The desorption studies showed that the V(V) ions could be desorbed by NH3·H2O easily. In the cleaner production application of chromate, the mesoporous γ-AlOOH was synthesized in the Na2CrO4-NaAlO2-NaVO3-H2O solutions of the chromate production and then in situ adsorbed the V(V) ions. The results showed that the V(V) ions were removed effectively, so that the highly carcinogenic CaCrO4 containing Ca(VO3)2 residue which was obtained by the typical process of chromate production was eliminated. Therefore, green separation of V(V) ions to reduce waste pollution ensuring economy and feasibility could be expected. [ABSTRACT FROM AUTHOR]