Silicon carbide ramming paste for cathode of aluminum electrolysis cell and preparation method of silicon carbide ramming paste

Abstract

The invention discloses a preparation method of cathode silicon carbide ramming paste for an aluminum electrolysis cell, wherein the cathode silicon carbide ramming paste conducts heat, does not conduct electricity, is slightly shrunk in a using process and can effectively solve the problem that a cathode material is damaged due to unstable current and structural expansion in a working process ofa current electrolysis cell. According to the silicon carbide ramming paste for the cathode of the aluminum electrolysis cell, raw materials are silicon carbide fine powder, fine silicon powder and high-aluminum homogenized material fine powder; the raw materials are uniformly mixed for 36-48 h through ball milling, and ramming forming is performed by taking PAMA-6000 resin as a binding agent. Thecathode ramming paste prepared by the method has the characteristics of heat conduction, non-electric conduction, micro-shrinkage and the like, and perfectly solves a series of problems of cathode carbon blocks.

Description

technical field [0001] The invention relates to the technical field of a refractory material for smelting nonferrous metals, in particular to a cathode silicon carbide ramming paste for an aluminum electrolytic cell and a preparation method thereof. Background technique [0002] Aluminum is a good low-density conductive material, because of its excellent ductility and plasticity, in light structural materials such as automobiles, aviation and aerospace, construction industry materials such as aluminum alloy profiles, food packaging materials such as warehouse storage tanks, packaging Aluminum foil and other fields have been widely used. The method of producing aluminum in modern industry generally adopts the cryolite-alumina molten salt electrolysis method, and its main equipment is an aluminum electrolytic cell; that is, alumina is dissolved in the molten cryolite melt to form a uniform melt with good conductivity. Carbon materials are used as electrodes, electrochemical r...

AI Technical Summary

Problems solved by technology

[0005] The present invention aims to overcome the problem of damage caused by electrical conduction and expansion that often occurs in existing cathode carbon pastes for aluminum electrolytic cells. Preparation method of cathode silicon carbide ramming paste for aluminum electrolytic cell due to current instability and structural expansion during the process

In the present invention, since silicon carbide with excellent thermal conductivity and low electrical conductivity is used to replace the current conductive carbon material, the problem of current instability in the currently used materials is solved; at the same time, a small amount of high aluminum is added to the material. The chemical material makes the prepared material shrink slightly during use, which solves the problem of structural damage caused by expansion during the working process of the material; when silicon carbide is partially oxidized, a low melting point glass phase SiO will be generated 2 , the Al in the high-alumina homogenized material added at this time 2 o 3 It can react with it to form mullite with a high melting point, which can improve the high temperature performance of the material; in addition, due to the use of a new type of resin binder, it solves the conductive problem of the currently used materials due to the binder

Due to the adoption of the above targeted measures, the cathode ramming paste prepared by the present invention has the characteristics of heat conduction, non-conduction, micro-shrinkage, etc., which perfectly solves a series of problems that occurred before the cathode carbon block