CN1003458B

CN1003458B - Anode

Info

Publication number: CN1003458B
Application number: CN87105073.0A
Authority: CN
Inventors: 姚广春; 邱竹贤
Original assignee: Northeastern University China
Current assignee: Northeastern University China
Priority date: 1987-09-01
Filing date: 1987-09-01
Publication date: 1989-03-01
Also published as: CN1030619A

Abstract

The invention provides an electrode for producing aluminum or aluminum-based rare earth alloy, which is made of a carbon material containing a rare earth compound. The invention is used as the anode of the electrode in the prior art, can reduce the overvoltage of the anode by 100-300 millivolts, and saves 300-1000 ℃ of electric energy for producing each ton of aluminum or aluminum-based rare earth alloy.

Description

Anode

The invention relates to an anode for the electrolytic production of aluminium or aluminium-based rare earth alloys.

The present production process of aluminium or aluminium-base rare earth alloy is to electrolyze aluminium oxide in cryolite solution, and the used anode is made up by using pure carbon. During the electrolysis process, the carbon reacts slowly with oxygen ions discharged from the anode, so that the overvoltage of the carbon anode reaches 400-600 millivolts, which accounts for 9-14% of the cell voltage. Therefore, the electric energy wasted by the carbon anode in the existing process accounts for 8-10% of the total electric energy consumed by electrolysis, and the overvoltage of the anode is reduced by an invalid method at present.

The invention aims to overcome the defects, improve the existing carbon anode and provide a novel electrode capable of reducing the overvoltage of the anode.

In order to achieve the above object, the present invention provides an electrode, characterized in that the electrode is made of a carbonaceous material containing 0.5 to 5.0% of a rare earth compound. The concrete method is that the rare earth carbonate or the rare earth oxide is added into the melted asphalt according to the content, and then the mixture is added into the forged coke after being stirred and mixed evenly, and then the mixture is kneaded. This makes it possible to uniformly distribute the rare earth compound on the surface and inside of the electrode. The rare earth carbonate is a mixture of carbonates of light rare earths such as cerium carbonate, lanthanum carbonate and neodymium carbonate, and the rare earth oxide is a mixture of oxides of light rare earths such as cerium, lanthanum and neodymium.

The carbon electrode containing rare earth compound is used as the anode of the electrode, has higher chemical reaction activity, and can accelerate the chemical reaction between carbon and oxygen ions, thereby reducing the overvoltage of the anode. The content of rare earth compounds in the electrode is too low. The catalytic effect is not significant, and an excessively high content may contribute to an increase in the manufacturing cost and an increase in the specific resistance of the electrode. Therefore, the content of the rare earth compound in the carbon of the electrode provided by the invention is within the range of 0.5-5.0%.

The electrode provided by the invention is used as an anode in the process of producing aluminum or aluminum-based rare earth alloy by electrolysis by adopting the existing process, and the overvoltage of the anode can be reduced by 100-300 millivolts, so that the cell voltage is reduced by 3-7% compared with the original cell voltage. Therefore, the method can save 300-1000 ℃ of electric energy for producing each ton of aluminum or aluminum-based rare earth alloy.

Therefore, the electrode provided by the invention is adopted in the existing production process of aluminum or aluminum-based rare earth alloy, so that the obvious economic benefit can be brought to enterprises.

Example 1.

When the electrode contains 0.5% of rare earth carbonate and the rest is carbon, the overvoltage of the anode can be reduced by about 100 millivolts, and the electric energy is saved by about 300 ℃ per ton of aluminum produced.

Example 2.

When the electrode contains 5.0% of rare earth carbonate and the balance of carbon, the overvoltage of the anode can be reduced by 250-300 millivolts. When the rare earth alloy is used for producing aluminum-based rare earth alloy, the rare earth content can reach 0.3-0.5%, and the electric energy can be saved by 800-1000 ℃ per ton of aluminum-based rare earth alloy.

Claims

1. An anode for producing aluminum or aluminum-based rare earth alloy, characterized in that the anode is made of a carbonaceous material containing 0.5-5.0% of a rare earth compound, wherein the rare earth compound can be rare earth carbonate or rare earth oxide.