Abstract: The distributions of Al species in different Al-ligands solutions were studied systematically bYUsing a microcolumn packed with weakly acidic cation-exchange resins coupled with ICP-AES. At pH=6.0, all labile monomeric Al species were retained on the microcolumn while non-labile monomeric Al species were directly passed through the column. The Al-ligands systems studied include Al-fluoride, Al-phosphate, Al-citrate, Al-oxalate and Al-EDTA. The effects of different Al-to-ligand molar ratios on the speciation were studied at a certain pH value, and some practised rules were obtained.

Key words: LMW-Al, Speciation, Cation-exchange microcolumn, ICP-AES