Properties： It is a white crystal or powder with relative density of 2.882(25℃). It is insoluble in most organic solvents, hydrofluoric acid and liquid HF. It is stable, even doesn't react with liquid ammonia and concentrated sulfuric acid by heating to fuming, isn't changeable when co-melted with KOH and can't be reduced by hydrogen. It doesn't decompose through heating, but sublime. The sublimation temperature is 1291℃. It decomposes partly to HF and aluminium oxide at 300-400℃. It is toxic.
Usages：It is used in electrolyzing bath in the aluminium production to decrease the melting point and increase the conductivity of electrolytes, as a zymotic inhibitor in the alcohol production, as a flux for glaze and enamel of pottery, also as a flux for non-iron metal, in fluxing solution of metal jointing, in the manufacture of optical lens. It is also used as catalyst in organic synthesis, as material of synthetic cryolite.
Execute standard：GB/T4292-1999