FREMGANGSMAATE FOR FREMSTILLING AV VANNFRITT MAGNESIUMKLORID UT FRA MG-HOLDIGE SULFATER OG/ELLER KLORIDER

摘要

Anhydrous MgCl2 and KCl is recovered from carnallite mineral ore by (a) dissolving the one in the minimum amount of water required to obtain complete solubility (b) filtering out any residual precipitates (c) adding ethylene glycol to the filtrate of (b) to solubilize all MgCl2 present in the filtrate, (d) dehydrating the resultant solution of step (c) by distillation to obtain an anhydrous solution of MgCl2 in ethylene glycol and an anhydrous KCl precipitate and removing the precipitate (e) adding anhydrous NH3 to the MgCl2 solution forming MgCl2.6NH3 precipitate filtering off the precipitate, washing with a low molecular weight solvent for ethylene glycol, the solvent having previous been saturated with anhydrous NH3 and (f) heating the washed precipitate to drive off NH3. Alternatively the MgCl2 and K2SO4 are recovered by (a) dissolving a mixed double salt of Mg and K sulphates in water at 50 to 90 DEG C and filtering off the residue (b) adding KCl to the filtrate, (c) heating solution of (b) at 50 to 90 DEG C, (d) adding ethylene glycol to resultant solution from (c) to fully dissolve all MgCl2 and removing precipitated K2SO4 (e) distilling water from the solution of (d) to form an anhydrous MgCl2 solution in ethylene glycol and a precipitate of K2SO4 and removing the precipitate (f) combining the K2SO4 precipitate of steps (d) and (e) and washing with water and (g) treating the anhydrous solution of MgCl2 in ethylene glycol as in steps (e) and (f) of the first embodiment.