Equilibrium and Structural Studies of Silicon(IV) and Aluminium(III) in Aqueous Solution. 28. Formation of Soluble Silicic Acid--Ligand Complexes as Studied by Potentiometric and Solubility Measurements.

Abstract

Amorphous silica solubilities in the presence of organic (mannitol, oxalate, citrate, catechol) and inorganic (SO 4 2− ) ligands have been studied in 0.6 M Na(Cl) medium at 25 o C. Apart from the catechol system, the experiments were performed at neutral pH with an equivalent ligand concentration of ≤0.6 M. In the presence of mannitol, the solubility of SiO 2 (am) was found to decrease with increasing ligand concentration. With oxalate, citrate and sulphate, an increased solubility was observed