Apparatus for the production of a metal by electrolyzing halides in a molten salt bath, by a simultaneous continuous double deposit

• US 4,686,025 A
• Filed: 02/10/1986
• Issued: 08/11/1987
• Est. Priority Date: 03/12/1984
• Status: Expired due to Fees

• Current Assignee: Pechiney SA
• Original Assignee: Pechiney SA
• Inventors: Cohen, Joseph, Lorthioir, Gerard
• Primary Examiner(s): Williams, Howard S.
• Application Number:
  US06/827,535
• Time in Patent Office: 547 Days
• Field of Search: 204/245, 204/246, 204/247, 204/64
• US Class Current: 204/245
• CPC Class Codes: C25C 3/00 Electrolytic production, recovery or refining of metals by electrolysis of melts C25C5/00 takes precedence
• CPC Class Codes: C25C 3/26 of titanium, zirconium, hafnium, tantalum or vanadium
• CPC Class Codes: C25C 7/005 of cells for the electrolysis of melts C25C7/02 - C25C7/06 take precedence

Abstract

This invention relates to a cell for producing a metal by electrolyzing halides in a molten salt bath. It consists of using one cathode in the form of a basket, simultaneously passing a current I₁ between this cathode and an anode in such a manner as to carry out a first deposit of crude metal in the basket and a current I₂ between the said basket and complimentary cathodes for depositing the final metal thereon. The cell consists of a central anodic system, a tubular cathodic basket surrounding the anode and a series of cathodes surrounding this basket, a positioning which cathodes can be reversed in relation to the basket.

Claims

1. An electrolytic cell for electrolyzing halides, of a metal to be deposited, contained in a molten halide bath, said cell comprising a vat structured to contain the bath in a non-reactive atmosphere, an anodic system consisting of at least one cylindrical-shaped anode (10) plunging in the bath (4), a cathode (14) in the form of a metal lattice basket suspended in the bath and comprising two vertical coaxial cylinders comprising an exterior wall (15) and an interior wall (16) connected to a base (17), extending to the axis of the cell, a halide feed system (19) positioned at the upper part of the cathode, means (9) within the two cylinders for drawing off the released halogen by suction, means joining (11) and (20), the upper parts of the anodic system and the cathode respectively to the positive and negative poles of a source of direct current, wherein the anode is positioned at the center of the cell and is surrounded symmetrically by the basket, and wherein at least one complimentary cathode (22) is jointed at its upper part to a source of current with a more strongly negative potential than that of the basket, said at least one complimentary cathode being positioned in the compartment demarcated by the interior walls of the cell and the exterior wall of the basket in a symmetrical manner, and means for withdrawing said at least one complimentary cathode from the bath.

2. A cell according to claim 1 wherein the base of the basket is double walled.

3. A cell according to claim 2 wherein the region between the double walls communicates with the interior of the basket.

4. An electrolytic cell for electrolyzing halides of a metal to be deposited, contained in a molten halide bath, said cell comprising a cylindrical vat structured to contain the bath in a non-reactive atmosphere, an anodic system consisting of at least one cylindrical-shaped anode (10) plunging in the bath (4), a cathode (14) in the form of a metal lattice basket suspended in the bath and comprising two vertical coaxial cylinders connected to a base (17) extending to the axis of the cell, a halide feed system (19) positioned at the upper part of the cathode and a means (9) within the two cylinders for drawing off the released halogen by suction, means joining (11) and (20), the upper parts of the anodic system and the cathode respectively to the positive and negative poles of a source of direct current, wherein at least one complimentary cathode (22), joined at its upper part to a source of current with a more strongly negative potential than that of the basket is positioned towards the center of the cell and is surrounded symmetrically by the basket, and wherein the anodic system is positioned in the compartment demarcated by the interior wall of the basket.

5. A cell according to claim 4 wherein the base of the basket is double walled.

6. A cell according to claim 5 wherein the region between the double walls communicates with the interior of the basket.