The purification of commercial Alizarin Red S for the determination of aluminium in silicate minerals

Abstract

Sephadex G-10 has been used to isolate sodium alizarin sulphonate from commercial samples of Alizarin Red S that contained variable and large amounts of inorganic salts. Aluminium in silicate minerals can be reliably determined with the purified reagent, which gives a linear response up to 180 µg of aluminium.