The effect of the surface roughness and ageing characteristics of boehmite on the removal of biological particles from aqueous solution

Abstract

Two-dimensional (2D) and one-dimensional (1D) quantum-sized γ-AlOOH structures were deposited onto siliceous and cellulosic substrates in a one-step, aqueous, and moderate temperature process. Low cost, large scale manufacturing of siliceous and cellulosic substrates coated with 2D and 1D arrays of γ-AlOOH crystallites of 2.7 ± 0.5 nm in diameter, with an average height of 3 ± 2 nm and 250 ± 50 nm, respectively was demonstrated. Direct measurement of streaming potentials in NaCl aqueous electrolyte was accomplished in order to characterize the zeta potentials of the as mentioned surfaces. It was shown that the isoelectric point value of rough nanostructured surface is three pH units higher as compare to the flat crystalline γ-AlOOH surface, resulting in a high removal efficacy of submicron particles from aqueous suspension by the surfaces with combined microscale and nanoscale structures. Furthermore, ageing characteristics of the 2D and 1D γ-AlOOH crystallites were presented, which showed great removal efficiencies after seven to fourteen years of manufacturing.

Keywords

• two-dimensional (2d)
• one-dimensional (1d)
• point of zero charge (pzc)
• isoelectric point (iep)
• zeta potential
• electrical double layer (edl)
• electrokinetic phenomena (ekp)