Abstract: Tiron (1,2-dihydroxy-3,5-benzenedisulfonic acid sodium salt) was used as a dispersant for nano-sized alumina suspensions. Surface chemistry of the suspensions
was evaluated via isotherm adsorption and ζ potential measurements. FTIR was used to probe the adsorption mechanism. It was found that the strong adsorption
should be due to the formation of an inner sphere complex between metal ions on the surfaces and alcohol groups of Tiron. With two sulfate groups, Tiron addition in the suspension led to a higher density of negative charge. The rheological
measurements of Al₂O₃ suspensions indicated that the optimum content of Tiron was 0.8wt% at pH=8.5.

Key words: alumina, l, 2-dihydroxy-3, 5-benzenedisulfonic acid sodium salt, adsorption, FTIR