Abstract:The initial crystal temperature of electrolyte increases with the increase of molecular ratio of aluminum electrolyte. On the contrary, the primary crystal temperature decreases. The accurate determination of molecular ratio of aluminum electrolyte has important guiding significance for the production. Among several methods of molecular ratio determination, X-ray diffraction (XRD) is widely used in electrolytic aluminum enterprises due to its advantages of simple sample preparation and fast analysis speed. However, with the complexity of aluminum electrolyte components, many companies have found that the molecular ratio determined by XRD could not well guide the production, and the determination results have great difference from those obtained by chemical analysis. Because the principle and influencing factors of molecular ratio determination by XRD are not clear enough, it is difficult to find out the reason for the difference. In view of the above problems, the determination principle of molecular ratio by XRD was analyzed. The theoretical formula for the determination of molecular ratio of complex aluminum electrolytes by XRD was derived, and the phase and diffraction peak were given. The reasons of inaccurate measurement results were investigated, which had a certain guiding role for the industrial development.
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