Effect of NaCl and LiF on liquidus temperature of molten cryolite-based aluminum electrolyte

Abstract

A new method for measurement of liquidus temperature of aluminum electrolyte system with one meter connected to COM port of a computer is introduced.Liquidus temperature is determined based on cooling curve by using thermal analysis method.Liquidus temperatures of NaF and NaCl are measured for comparison.The results prove the method to be reliable and accurate.The range of error is about 1-1.5 ℃ from 801 ℃ to 995 ℃.The effects of NaCl and LiF on liquidus temperature of molten cryolite-based aluminum electrolyte are studied and the mathematical model is established based on the experimental results obtained by this method.The mathematical model obtained is T=947.588-5.907×w(LiF)-6.223×w(NaCl).The experiments show that the mix addition of NaCl and LiF into molten cryolite-based aluminum electrolyte not only reduces effectively the liquidus temperature of electrolyte but also decreases the production cost and increases the economic benefits.