Pitch-free bonding cathode carbon block material for aluminium electrolysis cell and production method of pitch-free bonding cathode carbon block material

Abstract

The invention discloses a pitch-free bonding cathode carbon block material for an aluminium electrolysis cell and a production method of the pitch-free bonding cathode carbon block material. The production method of the pitch-free bonding cathode carbon block material comprises the following steps: carrying out dry blending on 60%-98% of calcined coke with different grains and 2%-50% of artificial graphite in weight percentage until the mixture is uniform, then adding 7%-13% of modified phenolic resin in weight percentage, carrying out wet mixing until the mixture is uniform and then discharging; ageing the wetly mixed material for 24-48 hours at room temperature and then placing the aged material into a normal-temperature moulding die for vibration moulding, or directly placing the wetly mixed material into the moulding die for moulding without aging; and carrying out roasting, machining and the like, so that the finished cathode carbon block product is obtained. The production method of the pitch-free bonding cathode carbon block material has the advantages that modified phenolic resin is adopted as a bonding agent, so that harm to a human body and environment pollution caused by a pitch bonding agent in the prior art are alleviated; the production method of the pitch-free bonding cathode carbon block material realizes that material mixing and moulding operation are carried out at room temperature; the cathode carbon block produced by the production method has the characteristics of high strength, good thermal conductivity, high electrical conductivity and molten salt corrosion resistance, and the service life of the aluminium electrolysis cell with the cathode carbon block can be effectively prolonged.

Description

technical field [0001] The invention relates to a cathode carbon block for an aluminum electrolytic cell, in particular to a cathode carbon block without asphalt combination and a production method thereof. Background technique [0002] The part in the aluminum electrolytic cell that is in contact with the aluminum liquid and the electrolyte is made of cathode carbon blocks. During the electrolysis process, the cathode carbon blocks are not only the cathode, but also directly contact the aluminum liquid and the electrolyte. The life of the cathode carbon blocks directly affects the For the life of the electrolyzer, the cathode carbon block must have the characteristics of high temperature resistance, molten salt corrosion resistance, good electrical and thermal conductivity, high mechanical strength, and strong corrosion resistance to sodium and fluoride salts. [0003] At present, the cathode carbon blocks in the industry are divided into three categories: anthracite cathod...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a kind of pitch-free bonded cathode carbon block material and its production method for aluminum electrolytic cells, to solve the problem of using pitch or modified pitch as a binder in the production of cathode carbon blocks in the prior art. The technical problem that kneading and vibration forming need to be carried out at a temperature greater than 100°C; at the same time, it reduces the porosity left by the volatilization of the existing binder during the heating process, and improves the strength of the cathode carbon block and its resistance to molten salt erosion.