| Aluminum reduction cells with inert anodes and wettable cathodes have been proved to be of great significance in saving energy, reducing pollution, and increasing efficiency in the process of aluminum electrolysis. While the research on inert anode has achieved great improvement through efforts of researchers, it still cannot meet the demand of corrosion resistance in recent electrolyte system and technological conditions. Aluminum electrolysis at low temperature can improve the working condition of inert anode, reduce the corrosion rate of inert anode, and then bring about the industrialization of inert anode.Funded by the State Key Project of Fundamental Research (973 project:2005CB623703) and National High Technology Research and Development Project (863 project:2008AA030503), and with the aim to explore electrolytic process of NiFe2O4 based inert anode at low temperature, represented by 5Cu/(NiFe2O4-10NiO) cermet inert anode, and based on Na3AlF6-K3AlF6-AlF3 system, the effects of composition and superheat of melts on electrolytic corrosion behavior of this anode are studied systematically. The composition and electrolytic parameters which are beneficial to improve the working condition of inert anodes is pointed out. Meanwhile, the electrical conductance of Na3AlF6-K3AlF6-AlF3 melts is studied systematically. In addition, the effects of LiF on liquidus temperature, dissolving ability of Al2O3(solubility and dissolution), and electrical conductance of melts are studied, which provides theoretical foundation for exploring novel electrolyte with "Low liquidus temperature, Favorable Al2O3 solubility and High electrical conductivity". The main results of the thesis can be summarized as follows:(1) The influence of melt components of Na3AlF6-K3AlF6-AlF3 low temperature electrolyte and superheat of melts on corrosion rate of 5Cu/(NiFe2O4-10NiO) cermet inert anode is indicated. The melt component which is beneficial to reduce the anode corrosion rate is that KR(the weight percent of K3AlF6 in (Na3AlF6+K3AlF6)) is ranging from 20% to 40%, and AlF3 content is ranging from 23% to 28% (correspondingly, liquidus temperature ranging from 830℃to 850℃). In this composition range, the corrosion rate of inert anode is 0.8cm/y while the superheat is 20℃and anode current density is 0.95 A/cm2(Calculation according to all the bottom area of anode), which is significantly decreased by 85%, compared with 5.27cm/y in Na3AlF6-AlF3 electrolyte(the cryolite ratio is 2.3, the liquidus temperature is 951℃, and the superheat is 15℃).(2) The influence of melt temperature, AlF3 content, and KR on electrical conductivity of Na3AlF6-K3AlF6-AlF3 melts is indicated. A regression equation showing the relationship between electrical conductivity of melts and melts composition and temperature is built. The ternary isotherm diagram of Na3AlF6-K3AlF6-AlF3 melts at 20℃superheat is drawn, too. The regression equation is as follow. The correlation coefficient of regression equation is 0.99 and its standard deviation is 0.027Ω-1·cm-1.The electrical conductivity with various compositions can be obtained in regression equation and ternary isotherm diagram, and the compositions range with various electrical conductivity can be obtained, which provides application basis for obtaining an electrolyte with low liquidus temperature, favorable Al2O3 solubility, and high electrical conductivity.(3) The influence of addition of LiF on the liquidus temperature, dissolve ability of Al2O3, and electrical conductivity of melts is indicated. An electrolyte of low liquidus temperature, favorable Al2O3 solubility, and high electrical conductivity are studied and designed. The addition of LiF reduces the liquidus temperature of melts and the solubility of Al2O3 in melts but increases the electrical conductivity of melts. For this low temperature electrolyte, which has low liquidus temperature, favorable Al2O3 solubility, and high electrical conductivity, its compositions at 800 ℃,850℃and 900℃can be described respectively as follows:KR, ranging from 30％to 40％and AlF3 content,ranging from 25.1％to 27.6％,with 2％of LiF(the superheat is ranging from 20℃to 40℃)；KR,ranging from 10％to 30％and AlF3 content,ranging from 24.5％to 27.7％,with 2％of LiF(the superheat is 40℃)；KR,ranging from 10％to 20％and AlF3 content,ranging from 16.7％to 21.3％,with 2％of LiF(the superheat is ranging from 20℃to 40℃).
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