Abstract: Long-sphere like hierarchical γ-AlOOH was prepared by a facile template-free hydrothermal method at 180 ℃ for 12 h with aluminum nitrate (Al(NO3)3·9H2O) as an aluminum source and urea as a homogeneous precipitation solvent.The obtained sample was characterized by X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy and N2 adsorption desorption technique, respectively.The possible formation mechanism of the long-sphere like γ-AlOOH was discussed.The adsorption properties for Cr(VI), Methyl orange, Congo red were also examined.The results indicate that the size of the obtained long-sphere like hierarchical γ-AlOOH is an average length of 1.5 μm and an avarege width of 1 μm.The sample has the specific surface area of 146.33 m2/g and an average pore volume of 0.37 cm3/g.Also, the hierarchical γ-AlOOH shows the superior removal efficiency for Cr(VI), Methyl orange and Congo red with the maximum adsorption capacities of 14.36, 84.93 and 258.02 mg/g, respectively.

Key words: boehmite;long-sphere like;hydrothermal method;adsorption