Metal electrode for aluminum electrolysis, coating composition thereof, and preparation method therefor

Abstract

A metal electrode for aluminum electrolysis, a coating composition of the metal electrode for aluminum electrolysis, and a method for preparing the metal electrode for aluminum electrolysis. The coating composition, by mass fraction, includes: NiFe 2 O 4 : 65%-75% and a metal component: 25%-35%. The chemical constituents of the metal component include: Ni, Fe, and Y.

1 . A coating composition of a metal electrode for aluminum electrolysis, comprising, by mass fraction, NiFe 2 O 4 : 65%-75% and a metal component: 25%-35%, wherein chemical constituents of the metal component comprise: Ni, Fe, and Y. 
     
     
         2 . The coating composition according to  claim 1 , wherein the chemical constituents of the metal component, by mass fraction, comprise: Ni: 55%-65%, Fe: 35%-45%, and Y: 0.5%-1.5%. 
     
     
         3 . The coating composition according to  claim 1 , wherein the coating composition is in a granular form; optionally
 a volume particle size of the coating composition ranges from 55 μm-70 μm.   
     
     
         4 . A metal electrode for aluminum electrolysis, comprising a substrate and a coating attached to the substrate, wherein a composition of the coating comprises the coating composition according to  claim 1 . 
     
     
         5 . The metal electrode for aluminum electrolysis according to  claim 4 , wherein a thickness of the coating ranges from 250 μm-350 μm; and/or
 the substrate is a NiFe metal anode. 
 
     
     
         6 . A method for preparing a metal electrode for aluminum electrolysis, comprising:
 obtaining a NiFe 2 O 4  powder;   obtaining a metal component powder;   mixing the NiFe 2 O 4  powder and the metal component powder to obtain a coating composition; and   coating the coating composition to a surface of a substrate to obtain a metal electrode for aluminum electrolysis.   
     
     
         7 . The method for preparing the metal electrode for aluminum electrolysis according to  claim 6 , wherein the obtaining the NiFe 2 O 4  powder, comprises:
 mixing NiO and Fe 2 O 3 , and then calcining to obtain a NiFe 2 O 4  powder;   optionally, a molar ratio of the NiO and Fe 2 O 3  is 1:1;   optionally, a temperature of the calcining ranges from 900° C.-1050° C.;   optionally, an atmosphere of the calcining is an air atmosphere.   
     
     
         8 . The method for preparing the metal electrode for aluminum electrolysis according to  claim 6 , wherein the obtaining the metal component powder, comprises:
 smelting Ni, Fe, and Fe—Y intermediate alloy, and then granulating to obtain the metal component powder;   optionally, the granulating is performed in a way of a vacuum atomization;   optionally, a volume particle size of the metal component powder ranges from 44 μm-60 μm.   
     
     
         9 . The method for preparing the metal electrode for aluminum electrolysis according to  claim 6 , wherein the mixing the NiFe 2 O 4  powder and the metal component powder to obtain a coating composition, comprises:
 dispersing the NiFe 2 O 4  powder and the metal component powder in a solvent, and then performing a spray granulation to obtain a coating composition;   optionally, the solvent is a deionized water;   optionally, a volume particle size of the coating composition ranges from 55 μm-70 μm;   optionally, process parameters of the spray granulation comprise: a processing capacity ranging from 45 kg/h-55 kg/h, an atomization pressure ranging from 3 MPa-5 MPa, and a discharge temperature ranging from 85° C.-95° C.   
     
     
         10 . The method for preparing the metal electrode for aluminum electrolysis according to  claim 6 , wherein the coating is performed in a way of a spraying;
 optionally, the spraying adopts a plasma spraying process;   optionally, process parameters of the plasma spraying process comprise: a powder-feeding gas flow rate ranging from 0.5 m 3 /h-0.6 m 3 /h, a spray gun moving speed ranging from 900 mm/min-1000 mm/min, and a spraying distance ranging from 80 mm-100 mm;   optionally, a coating thickness of the coating ranges from 250 μm-350 μm.