The cathode carbon block of electrolytic aluminum is a carbon block made of high-quality anthracite, coke, graphite and other raw materials, which is used as the cathode of aluminum reduction cells. It is built at the bottom of the electrolytic cell, also called the bottom carbon block. The cathode carbon block of electrolytic aluminum is a carbon block made of highquality anthracite, coke, graphite and other raw materials, which is used as the cathode of aluminum reduction cells. It is built at the bottom of the electrolytic cell, also called the bottom carbon block. The cathode carbon block is an important part of the aluminum electrolysis cell, which is conducive to energy saving and cell life improvement in aluminum electrolysis production. The cathode carbon block plays a dual role of conducting electricity and forming the inner lining of the electrolysis cell. The aluminum electrolysis production requires that the cathode carbon block be resistant to high temperature. The cathode carbon block in the electrolytic cell is in direct contact with the high temperature aluminum solution and highly corrosive electrolytes (NaF, AlF3) for a long time, which leads to the penetration and corrosion of the electrolyte to the cathode carbon block. Therefore, after 3-6 years of operation of a new electrolytic cell, the maintenance of the electrolytic cell should be carried out, and the waste cathode carbon block inside should be cleaned and replaced.