Solubility and solution mechanisms of chlorine and fluorine in aluminosilicate melts at high pressure and high temperature

The solubility and solution behavior of F and Cl in peralkaline aluminosilicate compositions in the systems Na2O-Al2O3-SiO2 and K2O-Al2O2O3-SiO2 have been determined for glasses quenched from melts equilibrated at 1400 and 1600 degrees C in the 1.0-2.5 GPa pressure range. With Al/(Al+Si) increasing from 0 to 0.33 in sodium aluminosilicate melts, F solubility (saturation concentration) increases from 3.3 to 7.4 mol%, whereas Cl solubility decreases from 5.7 to 2.5 mol%. There is no difference in F solubility in sodium or potassium aluminosilicate melts. However, the Cl solubility in potassic aluminosilicate melts is 40-60% lower than in sodic melts with the same AU(Al+Si) and Na or K mole fraction.