This paper describes the effects of hydrogen halide (hcl or hbr) concentration and temperature on the solubility and hydration state of alcl3, cacl2, cocl2, licl, mgcl2, nicl2, kcl, nacl, albr3, cobr2, pbbr2, mnbr2, kbr, and nabr. Saturated aqueous solutions of the chloride and bromide salts were sparged with hcl and hbr gas, respectively, until acid saturation was reached. All salts except cobr2 and mnbr2 were sparged at 20 deg, 40 deg, and 60 deg c; cobr2 and mnbr2 were sparged only at 20 deg c. Increased acid concentration caused the salts to crystallize out because of the common ion effect for all investigated halides except pbbr2. Cobr2 and cocl2 crystallized out and had minimum solubilities at intermediate acid concentrations, and then increased in solubility because of the formation of bromide and chloride complexes at higher acid concentrations. PBbr2 was minimally soluble in water and increased in solubility as hbr concentration increased. The data agree with literature values obtained from long-term equilibrium tests. Hydration states of the salted-out chlorides and bromides were determined by a wet-residue method and depended on temperature and acid concentration.
Paper in Crystallization & Precipitation. Pergamon, Elmsford, New York, 1987, PP. 89-98