The leaching of celestite in sodium carbonate solution

Exchange of SO42? ions with F? ions in mineral celestite under hydrothermal conditions

“…It was found that the exchange of SO 4 2 À ions with CO 3 2 À in large bulk celestite crystals plates proceeds by a leaching process at low temperature (90 jC) [3]. Recently, Yoshino et al [4] found the first evidence that even under hydrothermal conditions, the conversion of celestite to strontianite is achieved by a solid state ion exchange mechanism.…”

Dry mechanochemical conversion of SrSO4 to SrCO3

“…Previous works [7][8][9] have showed that a superstoichiometric amount of sodium carbonate led to enhanced conversion of celestite to strontium carbonate. Obut et al [20] also showed that beyond a 20% excess of Na 2 CO 3 no significant increase in the conversion occurred.…”

“…The sulfide is then leached in hot water and strontium carbonate is precipitated using soda ash, ammonium bicarbonate and/or CO 2 [3,5,6]. In the second process, finely powdered celestite is reacted with hot sodium carbonate solution (>90 • C) to obtain SrCO 3 and by-product sodium sulfate by a double decomposition reaction [7][8][9]. Although the black ash method produces a higher purity SrCO 3 product it is more energy intensive than the double decomposition process.…”

The aqueous processing of minerals and materials

“…86 Iwai and Toguri concluded that a sodium carbonate leaching process for converting strontium sulfate (celestite) to strontium carbonate was thermodynamically and kinetically feasible. 87 The process appears to be competitive with the current commercial production process of high-temperature reduction of the sulfate using carbon, followed by leaching of the resultant strontium sulfide by sodium carbonate or carbon dioxide.…”