6 research outputs found
Système ternaire : H<sub>2</sub>O–Fe(NO<sub>3</sub>)<sub>3</sub>–Co(NO<sub>3</sub>)<sub>2</sub> isotherme : 30 °C
No full textSolubility Modeling of the Binary Systems Fe(NO<sub>3</sub>)<sub>3</sub>–H<sub>2</sub>O, Co(NO<sub>3</sub>)<sub>2</sub>–H<sub>2</sub>O and the Ternary System Fe(NO<sub>3</sub>)<sub>3</sub>–Co(NO<sub>3</sub>)<sub>2</sub>–H<sub>2</sub>O with the Extended Universal Quasichemical (UNIQUAC) Model
No full textSolvation phenomena and revision of solid–liquid equilibria in aqueous solutions of two precursors of mixed oxides, the hydrates of cobalt and nickel nitrates
No full textInternational audienc
Widespread Solid Solutions of Hexahydrated Cobalt and Nickel Nitrates: Solid–Liquid Equilibria at 273.15 and 303.15 K and Characterization of Mixed Crystals of Homogeneous Composition
No full textThe isothermal solubility curves
of the H<sub>2</sub>O–Co(NO<sub>3</sub>)<sub>2</sub>–Ni(NO<sub>3</sub>)<sub>2</sub> ternary
system were studied at 273.15 and 303.15 K, using a synthetic method
based on conductivity measurements. The analysis of the equilibrium
phases’ composition was conducted by UV–visible spectroscopy.
The solid phases were first characterized by powder X-ray diffraction,
which showed the formation of two substitutional solid solutions:
Co<sub>(1−σ)</sub>Ni<sub>σ</sub>(NO<sub>3</sub>)<sub>2</sub>·6H<sub>2</sub>O, which has a monoclinic structure,
and Ni<sub>(1−ω)</sub>Co<sub>ω</sub>(NO<sub>3</sub>)<sub>2</sub>·6H<sub>2</sub>O, which has a triclinic structure.
Then the evolution of the lattice parameters of the crystals at 303.15
K, depending on the solid solution composition, was studied by single-crystal
X-ray diffraction. The shrinkage of the monoclinic lattice increases
with the increase of the nickel ions in the structure. The stability
area of this solid solution is very wide as more than 7 cobalt ions
in 10 could be replaced by nickel ions. However, the variation of
the lattice parameters of the triclinic solid solutions remains limited,
although a small shift of the diffraction peaks is observed. This
is consistent with a limited composition area of the triclinic solid
solution, where less than 1 nickel ion in 10 could be replaced by
cobalt ions
