ABSTRACT

Equilibrium data of the NaOH NaBO2 Na2CO3 H2O quaternary system at 30 deg C, 60 deg C, and 100 deg C were measured by an isothermal method. The phase diagrams at 30 deg C and 100 deg C were constructed, and the crystallization zones were discussed. In the phase diagram, the quaternary system has two invariant points, five univariant curves, and four crystallization zones corresponding to NaBO2*4H2O (NaBO2*2H2O at 100 deg C), NaBO2*2H2O (NaBO2*1/3H2O at 100 deg C), Na2CO3*H2O, and NaOH*H2O (NaOH at 100 deg C). In addition, the solubility isotherms of NaBO2 in Na2CO3-saturated NaOH solution and the solubility isotherms of Na2CO3 in NaBO2-saturated NaOH solution were plotted. The solubility of Na2CO3 in NaOH solution was compared with that in NaBO2-saturated NaOH solution. On the basis of the solubility data, a strategy for the effective separation of NaBO2 and Na2CO3 from the NaOH NaBO2 Na2CO3 H2O quaternary system was proposed.

Compounds

#	Formula	Name
1	HNaO	sodium hydroxide
2	CNa2O3	sodium carbonate
3	BNaO2	sodium metaborate
4	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	2 4 3	Mass fraction - 2 ; Liquid	Temperature, K; Liquid Mass fraction - 3; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 1	titration + spectroscopy	3
POMD	1 4 3	Mass fraction - 3 ; Liquid	Temperature, K; Liquid Mass fraction - 1; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 1	titration + spectroscopy	3
POMD	1 4 3	Mass fraction - 3 ; Liquid	Temperature, K; Liquid Mass fraction - 1; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 2	titration + spectroscopy	3
POMD	2 1 4	Mass fraction - 4 ; Liquid	Temperature, K; Liquid Mass fraction - 1; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 2	titration + spectroscopy	3
POMD	2 1 4	Mass fraction - 4 ; Liquid	Temperature, K; Liquid Mass fraction - 1; Liquid	Pressure, kPa; Liquid	Liquid Crystal of intercomponent compound 2	titration + spectroscopy	3

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

Phase Equilibria of the NaOH-NaBO2-Na2CO3-H2O System at 30 deg C, 60 deg C, and 100 deg C

Qin, S.[Shiyue], Yin, B.[Baowen], Zhang, Y.[Yifei], Zhang, Y.[Yi]

ABSTRACT