The separation of aluminum(III) ions from the aqueous solution on membrane filter using Alizarin Yellow R

The membrane filtration was examined as an effective and selective method for collection of Al(III) ions from aqueous solutions using Alizarin Yellow R, one of a pH-indicator, as a precipitating reagent. For preparation of aqueous solutions without precipitate or turbidity, a non-ionic surfactant, Triton X-100, was used as a solubilizing reagent for insoluble materials. Three metal ions, Al(III), V(III) and Cu(II) ions, were able to be collected as yellow-orange precipitates from aqueous solutions controlled in a range of pH 4–7, pH 4–9, and pH 5.5–12, respectively, on a membrane filter by filtration under suction. Hydrogen peroxide and o-phenanthroline were found to be capable of masking V(III) and Cu(II) ions in a range of pH 5.5–8 in which Al(III) ions were collected. This membrane filtration was applied to selective separation and determination of Al(III) ions in tap water.