Den viktigste industrielle produksjonsmetoden for å produsere sjeldne jordmetaller ved elektrolyse av smeltet salt. På 1970-tallet hadde omfanget av elektrolyseceller for sjeldne jordartsmetaller nådd 50 000 ampere, med en årlig produksjon på tusenvis av tonn sjeldne jordmetaller, hovedsakelig ceriumblandede sjeldne jordmetaller, etterfulgt av metaller cerium, lantan, praseodym og neodym. I henhold til elektrolysesystemet for smeltet salt av sjeldne jordarter, kan det deles inn i to kategorier: RCl3-KCl (NaCl)-systemet, som elektrolyserer klorider av sjeldne jordarter; Det andre er RF3 LiF BaF2 (CaF2)-systemet, som elektrolyserer sjeldne jordartsoksider. Elektrolytten for kloridsystemelektrolyse er fremstilt fra 35-50% vannfri RCl3 og KCl. Urenhetsinnholdet (%) i råvarene er spesifisert som Fe2O3<0.07, Ca<3, Th<0.03. The electrolysis temperature is higher than the melting point of the metal, and the temperature for producing mixed rare earth metals and cerium by electrolysis is 850-900 ℃; The temperature for electrolytic production of lanthanum is 900-930 ℃; The temperature for electrolytic production of praseodymium neodymium alloy is about 950 ℃. Using a molybdenum rod as the cathode, the current density is 3-5 A/cm2. Using graphite as the anode, the current density is less than 1 ampere/cm2. The slot voltage is 8-9 volts, and the pole spacing is adjustable. The metal yield is 80-90%, and the purity is 98-99.5%. The electrolysis method can also be used to produce alloys of rare earths, aluminum, magnesium, and even transition metals. There are two methods based on their working principles: ① using liquid metals such as aluminum or magnesium as cathodes, electrolyzing Y2O3 or YCl3 in YF3 LiF or YCl3 KCl systems to reduce and precipitate Y3+on the liquid aluminum or magnesium cathode, generating Y-Al or Y-Mg alloys with yttrium content of up to 20% and 48%, respectively; ② Co precipitation of electrolytic alloy components to produce Y-Al and Y-Mg alloys. When producing Y-Al alloy by electrolysis, an electrolyte with a molar ratio of LiF: YF3=1:4 is used. Under the process conditions of electrolysis temperature of 1025 ℃ and cathode current density of 0.6 A/cm2, a mixture of Al2O3 and Y2O3 with an electrolysis content of 14-17% is electrolyzed. Y3+and Al3+are reduced and precipitated together on the cathode to form Y-Al alloy. When producing Y-Mg alloy by electrolysis, the electrolyte of YCl3-MgCl2-KCl system is used for electrolysis at 900 ℃, and Y3+and Mg2+ions are jointly reduced and precipitated on the cathode to form Y-Mg alloy.