The System Lithium Sulphate – Ammonium Sulphate – Water

Abstract

The binary eutectics Li3S04 .H?O -ice and (XI-I.i)?SOd -ice as \veil as tlie ternary eutectics LilSOl .HIO -Li?SD, .(KH4)1S04-ice and (NHr)2SOi-Li!S04.(NH,)?SOd-ice have been determined as to temperature arid composition. The colnplete solubility isotherms a t O.lO, 71.g0, and '35.2OC. have been investigated. l'he enthalpies of solution of lithium s~~l p h a t e monohydrate, of ammonium sulphate, and of double salt have been determined (in water .at room temperature), and from these data, as well as frorn tlie solubility isotherms, it has been sho\\:ll that the temperature of the transition of the double salt, LizSO.!. (NHl)PSOd, to its component single salts (in Lhe presence of water) is approached by lo\vering the temperat~~re, but this transition temperature is still far fro111 reached when the system freezes completely.