An inert electrodd refers to an electrode that is not easy to gain or lose electrons and generally does not react with the electrolyte. It consists of an inert material such as platinum, gold or graphite, and a solution containing soluble oxidized and reduced substances.

In the selection of inert electrodes, the main considerations are the physical, chemical and electrochemical interactions between the components in the electrolyte (including aluminum electrolyte and metal Al, Na) and the electrodes, and the physical and chemical properties of the electrode products themselves (such as electrical conductivity, heat vibration resistance, and machinability, etc.). It is generally believed that the performance of the inert electrode material should meet the following requirements:

(1) It is chemically inert to the molten electrolyte, that is, it does not dissolve, does not chemically react with the molten salt electrolyte, is not subject to penetration and erosion, and can resist air oxidation;

(2) Good electrochemical stability, that is, as an anode, no anodic dissolution occurs during anodic polarization, and it can resist electrochemical oxidation. It is very stable to the new ecological oxygen on the electrode and does not form an oxide film; as a cathode, it does not form compounds or alloys with cathode products, or do not undergo reduction by themselves;

(3) Good electronic conductivity;

(4) Excellent mechanical properties;

(5) Raw materials are easy to obtain;

(6) Easy to manufacture and process;

(7) The cost is not high.

The application of inert electrode materials has two advantages, one is economical and the other is environmental protection.

In terms of economy, it can replace carbon electrodes to save a large amount of high-quality carbon materials and save labor costs for electrode replacement. It can reduce the pole distance of electrodes, especially if the inert anode and inert cathode are used at the same time, it can greatly reduce the cost of electrolytic aluminum production. Energy consumption is expected to save up to 35%. At the same time, oxygen can be used as a by-product of the anode in the electrolytic aluminum production process, and its economic benefits can reach 3% of the primary aluminum production benefits.

In terms of environmental protection, the use of inert electrodes can eradicate the CO2 gas that produces the greenhouse effect, as well as the emission of other harmful gases such as CF4, C2F6, etc. in electrolytic aluminum, which is beneficial to the health of electrolytic aluminum production operators and national environmental protection requirements. Therefore, the application of inert electrode materials in production is bound to be of great significance to the progress of electrolytic aluminum production technology and the improvement of its economic benefits.