Solubility measurement of zirconium(IV) hydrous oxide

Abstract

The solubility of zirconium(IV) hydrous oxide was measured in the hydrogen ion concentration (pH

Hydrolysis Constant and Coordination Geometry of Zirconium(IV)

“…2,3) In our recent study, for example, the solubility of zirconium hydrous oxide was investigated by considering the presence of colloidal species. 4,5) The formation of polynuclear and colloidal species, of which a steady-state size distribution was reached within a few months, was observed in oversaturation experiments. From the size distributions of the apparent solubility data, it was found that mononuclear, polynuclear and colloidal species under 3 kDa in size might be present, even in acidic solution.…”

Solubility of Thorium(IV) in the Presence of Oxalic and Malonic Acids

“…In the present study, the mononuclear species of Th 4þ , ThOH 3þ , Th(OH) 2 2þ , Th(OH) 3 þ , and Th(OH) 4 (aq) were treated inclusively as a monomeric unit in the model similarly to our previous study on the Zr hydrolysis species. 14) The total number, Nðl 1 ; l 2 Þ, of monomeric units comprising the chain molecules in the range l 1 to l 2 in size is given by…”

Detection of Polynuclear Zirconium Hydroxide Species in Aqueous Solution by Desktop ESI-MS

“…Immediately after the preparation of the solution, the hydrolysis reaction and polymerization process began, depending on the pH and the aging period. 7) Samples aged for 3 months were used for measurements unless otherwise stated. The spectrum of the samples aged at pH c > 3 could not be obtained due to the low Zr solubility.…”

“…7,8) For instance, the formations of polynuclear and colloidal species, for which a steady state size distribution was reached after a few months, were observed in oversaturation experiments. 7) From the observed size distributions, it was found that 3 kDa mononuclear, polynuclear, and colloidal species (Microcon Centrifugal Filter, Millipore) might exist even in an acidic solution. It is interesting to note that further polymerization would occur very slowly after reaching a nearly steady state in 3 months.…”

“…[3][4][5][6] For instance, measuring the size distributions of such species by ultrafiltration (at 3 kDa), Sasaki et al proposed that mononuclear, polynuclear, and colloidal species coexist in weakly acidic and neutral pH solutions. 7) On the other hand, Cho et al developed a method by combining laserinduced breakdown detection (LIBD) with slow coulometric titration in order to sensitively detect the formation of tiny zirconium colloids (>5 nm in size) without the ultrafiltration process. 8) They detected a certain point corresponding to the formation of a $5 nm compound, which they regarded as the solubility limit.…”