Micro-raman spectra research on NaF-AlF3-NaCl melts

Abstract

Raman spectra of NaF-AlF3-NaCl melts with the compositions in aluminum electrolysis practice are recorded by using the ultraviolet laser source. A kind of sealed sample cell was used to improve the measuring precision. The ionic structure of the melts with different cryolite ratio (molar ratio between NaF and AlF3) and NaCl contents was studied. The effect of the composition and temperature was analyzed. The results show that with the addition of the NaCl to the acidic NaF-AlF3 melts, the relative contents of the Al-F entities have been changed greatly. It is thought that the relative contents of the complex ions are also greatly influenced by the temperature.