ABSTRACT

This study explores the possibility of using inorganic salts for temperature calibration of Differential Scanning Calorimeters (DSC) on cooling. The crystallization and melting of sodium nitrate, potassium nitrate, and rubidium nitrate has been studied at several cooling and heating rates. It has been found that these salts crystallize at almost the same temperature, at which they melt, meaning that they do not practically supercool. The DSC data have indicated that the median value of the supercooling is around 0.4-0.8 .C. The study suggests that the process of crystallization of these and possibly other inorganic salts can be considered for developing new standards to calibrate DSC on cooling.

Compounds

#	Formula	Name
1	NNaO3	sodium nitrate
2	KNO3	potassium nitrate
3	NO3Rb	rubidium nitrate

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	Phase	Method	#Points
POMD	1	Normal melting temperature, K ; Crystal	Crystal Liquid Air at 1 atmosphere	DTA:corrimp	1
POMD	1	Molar enthalpy of transition or fusion, kJ/mol ; Crystal	Crystal Liquid Air at 1 atmosphere	DSC	1
POMD	2	Normal melting temperature, K ; Crystal	Crystal Liquid Air at 1 atmosphere	DTA:corrimp	1
POMD	2	Molar enthalpy of transition or fusion, kJ/mol ; Crystal	Crystal Liquid Air at 1 atmosphere	DSC	1
POMD	3	Normal melting temperature, K ; Crystal	Crystal Liquid Air at 1 atmosphere	DTA:corrimp	1
POMD	3	Molar enthalpy of transition or fusion, kJ/mol ; Crystal	Crystal Liquid Air at 1 atmosphere	DSC	1

Thermodynamics Research Center / ThermoML | Thermochimica Acta

Crystallization of ionic salts for calibration of differential scanning calorimeters

McCulley, C.[Calla], Vyazovkin, S.[Sergey]

ABSTRACT