SOME PROPERTIES OF RARE EARTH-NITRILOTRIACETATE COMPLEXES

Technical Report · Thu Feb 01 04:00:00 EST 1962

OSTI ID:4815183

Levy, S C; Powell, J E

The stability constants of the 1: 1 and 1: 2 rare-earthNTA (nitrilotriacetate) complexes were measured at 10, 20, 30, and 40 deg C at an ionic strength of 0.10. The thermodynamic functions DELTA F/sup 0/, DELTA /sup 0/, DELTA S/sup 0/ were calculated for the 1: 1 and 1: 2 rare-earth-NTA complexes from the temperature dependence of the stability constants. It was found that the main driving force for chelation was a favorable entropy change. The solid 1: 1 rare-earth-NTA chelates were prepared at temperatures ranging from room temperature to 100 deg C. Analyses were done on all the chelates to determine their composition (waters of hydration), and thermal decompositions were done on the various hydrates found. The solubility of each hydratc of the rare-earth NTA chelates was measured at 25 and 60 deg C. Analysis of the solids in equilibrium with the saturated solutions indicated the most stable hydrate at each of these temperatures. (auth)

• Research Organization: Ames Lab., Ames, Iowa
• DOE Contract Number: W-7405-ENG-82
• NSA Number: NSA-16-022048
• OSTI ID: 4815183
• Report Number(s): IS-421
• Country of Publication: United States
• Language: English

Related Subjects

ACETATES
BINDING ENERGY
CHELATES
CHEMISTRY
CYANIDES
DECOMPOSITION
ENTHALPY
ENTROPY
MEASURED VALUES
NTA
ORGANIC COMPOUNDS
PREPARATION
QUALITATIVE ANALYSIS
RARE EARTHS
SOLIDS
SOLUBILITY
STABILITY
TEMPERATURE
THERMODYNAMICS
WATER