I want to dissolve tie nitrate salts (such as nickel nitrate hexahydrate) in toluene, and I tried but failed by stirring and heat. Does anyone have good ideas for this?
Rather than in pure toluene, where (anhydrous) nickel nitrate is quite insoluble, this salt is expected to dissolve, to some extent, in a few mixed solvents that may include toluene (a non-solvent for this salt) and at least another miscible solvent able to dissolve the salt. The salt can be then precipitated from a saturated mixed solution by further toluene addition. Also to be considered is the expected salting-out effect of the salt in solvent miscibility. Either the binary solvent mixture acetone–toluene, or the acetone–toluene–water (*) ternary solvent mixture could be considered for this purpose. Both water and acetone dissolve this salt; 2-propanol could substitute for acetone.
(*) Cf.: Article A STUDY OF THE TERNARY SYSTEM, TOLUENE-ACETONE-WATER