Separation of Nickel and Chromium by Porous Glass Packed Column Using Acetic Acid as Eluent

Abstract

Batchwise adsorption experiments showed that nickel and chromium were adsorbed from aqueous acetic acid solution on powdery porous glass in the pH 5.0 to 6.5 region and in the pH 2.2 to 3.3 regions respectively, at 298 K. In addition, the separation of nickel and chromium by porous glass packed column using acetic acid as an eluent was examined out at 298 K. The retention volumes of these metals decreased and the degree of overlap of the elution curves increased with increasing concentration of acetic acid. The retention volume of these metals was the maximum in the pH 2.2 to 3.0 region, due to low concentrations of both hydrogen ion and acetate ion. In this situation, the degree of overlap of the eluent curves was near zero when the acetic acid concentration of eluent was 1 mol/dm³ in the pH 2.0 to 2.2 region, 0.5 mol/dm³ at pH 2.7 or 0.1 mol/dm³ in the pH 2.2 to 4.5 region. Post-treatments with 3N hydrochloric acid for nickel and with 1 mol/dm³ acetic acid for chromium were effective to recover these metals completely when the retention volumes were large.