Experimental studies of interaction between water and albite melts

Abstract

On the basis of FTIR and Raman spectra studies on hydrous albite glasses, it is found that there exist two water solubility mechanisms in albite melts simultaneously. On the one hand, water interacts with Al —O°—Al to produce the Q 3 Al—OH, leading to depolymerization, and this results in the appearance of 4500 cm -1 in FTIR spectra and 900 cm -1 in Raman spectra. On the other hand, the exchange of H + in water with Na + in albite melt as charge-balancing cation occurs at the same time. In the initial stage, the production of Al —OH is the dominant solubility mechanism, at the stage of higher water contents, the exchange of H + with Na + becomes the important dissolution mechanism. The dissolution of water into albite melt can be expressed as H 2 O+ 3NaAlSi 3 O 8 = 2NaAl(OH)Si 3 O 7.5 +HAlSi 3 O 8 +NaOH.