ABSTRACT

In this study, the solubilities and densities of a ternary system (NaH2PO4 + CO(NH2)2 + H2O) at 298.15 K was investigated using isothermal solution saturation and moist residues. According to the experimental results, the phase diagram and the diagram of densities versus composition were plotted. It turned out that there were one cosaturated point (CO(NH2)2 + NaH2PO4*2H2O), two univariant curves, and two crystallization regions corresponding to NaH2PO4*2H2O and CO(NH2)2 in this ternary system. The system belonged to a simple eutectic type, in which no double salt was formed. This research filled the blank of phase diagram in this ternary system and demonstrated the absence of double salt in the system.

Compounds

#	Formula	Name
1	CH4N2O	urea
2	H2NaO4P	sodium dihydrogen phosphate
3	H2O	water

Datasets

The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type	Compound-#	Property	Variable	Constraint	Phase	Method	#Points
POMD	1 2 3	Mass density, kg/m3 ; Liquid	Mass fraction - 2; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 1	Pycnometric method	10
POMD	1 2 3	Mass density, kg/m3 ; Liquid	Mass fraction - 2; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid Crystal - 1	Pycnometric method	9
POMD	1 2 3	Mass density, kg/m3 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal - 1 Crystal of intercomponent compound 1	Pycnometric method	1
POMD	1 2 3	Mass fraction - 1 ; Liquid	Mass fraction - 2; Liquid	Pressure, kPa; Liquid Temperature, K; Liquid	Liquid Crystal of intercomponent compound 1	Titration method	10
POMD	1 2 3	Mass fraction - 1 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal of intercomponent compound 1 Crystal - 1	Titration method	1
POMD	1 2 3	Mass fraction - 1 ; Liquid	Mass fraction - 2; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid	Liquid Crystal - 1	Titration method	10
POMD	1 2 3	Mass fraction - 2 ; Liquid	Temperature, K; Liquid Pressure, kPa; Liquid		Liquid Crystal of intercomponent compound 1 Crystal - 1	Titration method	1

Thermodynamics Research Center / ThermoML | Journal of Chemical and Engineering Data

Phase Equilibrium in the Aqueous Ternary System NaH2PO4 + CO(NH2)2 + H2O at 298.15 K

Liu, M.[Mei], Tang, J.-h.[Jian-hua], Cui, C.[Chi], Li, C.[Cheng], Chen, X.-z.[Xi-zhou]

ABSTRACT