Patent · US Expired

Process for producing aluminum

US3996117A · kind A · utility

20Cited by
7References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 27, 1974
Grant dateDec 7, 1976
Priority date
Expiry dateMar 27, 1994

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC25C3/18
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

In a process for producing aluminum, which process conventionally includes electrolytically decomposing alumina to aluminum metal in a molten electrolyte bath between a carbon anode and a cathodic interface formed between a molten aluminum metal pad and sides electrolyte bath, the bath PA1 A. being predominantly NaF and AlF.sub.3, PA1 b. containing CaF.sub.2 and Al.sub.2 O.sub.3, and PA1 C. being covered by a frozen crust, The improvement including providing in the bath 5 to 10 weight-% LiF, while maintaining in the bath a weight ratio NaF to AlF.sub.3 of 1.04 to 1.15, and while maintaining a frozen layer bounding the sizes of the aluminum metal pad and bath.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.