Molten salts
HEAT TRANSFER FLUIDS - PROPERTIES

The most common molten salts are formed from sodium nitrite (NaNO₂), sodium nitrate (NaNO₃) and potassium nitrate (KNO₃). Their main advantages are that they can operate at atmospheric pressure for temperatures between 150 and 550°C. Taken separately, these salts are only liquid above 300°C, but eutectics with significantly lower melting points can be produced.

The most common eutectics are in mass composition:

• a mixture of 40% sodium nitrite, 53% potassium nitrate and 7% sodium nitrate. This mixture, known as HTS1 (Heat Transfer Salt 1 ), is a white granulate in the solid state and a pale yellow liquid above its melting temperature of 142°C. Used between 150 and...