Colorless monoclinic or hexagonal crystals; transforms to cubic form at 500°C; refractive index 1.465; density 2.221 g/cm3; sublimes at 845°C; soluble in water, solubility decreases with an increase in temperature (26.1 and 23.2 g at 0 and 100°C, respectively); insoluble in absolute ethanol and acetone.
The monohydrate constitutes colorless monoclinic crystals; refractive index 1.465; density 2.06 g/cm3; loses water of crystallization at 130°C; soluble in water, (more soluble than the anhydrous salt (34.9 and 29.2 g/100g at 25 and 100°C), respectively; insoluble in acetone and pyridine.
Lithium sulfate monohydrate is used in making a special type of high strength glass. It also is used in medicine as an antidepressant,used in preparation of lithium standard solutions.
Lithium sulfate monohydrate is used in solar panels and potential for a new class of battery. It is also used to treat bipolar disorder and in ultrasound-type non-destructive testing. It is also used as an additive for portland cement to speed up the curing. It is also involved as a catalyst in the elimination reaction for the conversion of n-butyl bromide to 1-butene.
Lithium sulfate monohydrate may be used in the preparation of Cu(II) doped lithium sulfate monohydrate (LSMH) crystal.
Lithium sulfate is prepared by neutralization of lithium hydroxide or lithium carbonate with sulfuric acid followed by crystallization:
2LiOH + H2SO4 → Li2SO4 + H2O
Li2CO3 + H2SO4 → Li2SO4 + CO2 + H2O
The product obtained from crystallization in a concentrated solution is the monohydrate, Li2SO4•H2O. Anhydrous salt is obtained by heating the monohydrate in a vacuum.
