Hall-Hdroult process

Despite millions of dollars being spent on new processes, there is no alternative process able to take over for the Hall-Hdroult process in the next decades. 

Cryolite (Na3AlFg) is the main component of the bath used in the aluminium electrowinning by the Hall-Hdroult process. Alumina (AI2O3) is dissolved in the bath as the source of aluminium and the operating temperature is usually varied from 940 to 960 °C. The structure of cryolitic melts has been widely studied using different techniques such as cryoscopy [1], thermodynamic calculations [2] or Raman spectroscopy [3], Recently, high-temperature (HT) NMR spectroscopy became a powerful tool to determine in situ the structure of molten cryolitic systems [4-7],... 

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