Potentiometric studies on the binary complexes of N-[tris(hydroxymethyl)methyl]glycine with Th{sup 4+}, Ce{sup 3+}, La{sup 3+}, and UO{sub 2}{sup 2+} and medium effects on a Th-tricine binary complex
- Minia Univ., El-Minia (Egypt)
- Assiut Univ. (Egypt)
The stability constants for M{sup n+}-tricine binary complexes (1:1 and 1:2), where M{sup n+} = Th{sup 4+}, Ce{sup 3+}, La{sup 3+}, and UO{sub 2}{sup 2+} have been determined pH-metrically in aqueous media at 25 C and in the presence of 0.10 mol dm{sup {minus}3} (KNO{sub 3}). The binary Th-tricine (1:1) complex was studied in the presence of different organic solvents as well as in the presence of different ratios of dioxane and at different temperatures. The calculated stability constants have been discussed in terms of the nature of both the metal ion and tricine. It is suggested that tricine may act as a tridentate as well as a bidentate ligand. Solvent basicity and proportion in addition to the differences in stabilization of the free base by hydrogen bonding with solvent molecules as well as the electrostatic effect are the major factors responsible for the observed high stability of the Th-tricine binary complex. The thermodynamic parameters ({Delta}H, {Delta}G, and {Delta}S) for the formation of 1:1 Th-tricine complex in the presence of 40% (w/w) dioxane at different temperatures (5--45 C) were calculated.
- OSTI ID:
- 509418
- Journal Information:
- Journal of Chemical and Engineering Data, Vol. 42, Issue 3; Other Information: PBD: May-Jun 1997
- Country of Publication:
- United States
- Language:
- English
Similar Records
Complexation of lithium ion by the cryptand 4,7,13-trioxa-1,10-diazabicyclo(8. 5. 5)eicosane (C21C sub 5 ) in a range of solvents. A sup 7 Li nuclear magnetic resonance and potentiometric titration study
The rates and mechanisms of water exchange of actinide aqua ions: A variable temperature {sup 17}O NMR study of U(H{sub 2}O){sub 10}{sup 4+}, UF(H{sub 2}O){sub 9}{sup 3+}, and Th(H{sub 2}O){sub 10}{sup 4+}