Carbon Black, Acetylene Black

Acetylene carbon black is a high-purity acetylene obtained through the decomposition of by-products from calcium carbide or naphtha (crude gasoline) pyrolysis, followed by continuous pyrolysis to produce the carbon black. The reaction furnace is heated to above the decomposition temperature of acetylene, which is 800°C, and then acetylene is introduced to begin the thermal decomposition process. As it is an exothermic reaction, it can proceed automatically. To maintain stable quality, the reaction temperature should be kept around 1800°C. The furnace temperature can be controlled through the external water-cooled jacket of the reaction furnace. Acetylene carbon black is used as an anode material in manganese dry batteries, alongside manganese dioxide and electrolyte. Compared to furnace black, it has developed crystalline and secondary structures, thus exhibiting superior conductivity and wettability. Due to the low presence of heavy metals and other impurities, it has low self-discharge losses and good storage properties. Acetylene black has almost occupied the entire market and is expected to continue along with the demand for dry batteries in the future.

Acetylene carbon black is a very fine black powder, with a relative density of 1.95 (determined by nitrogen displacement method). The apparent density is 0.2 to 0.3 g/cm3. The average particle size is 30 to 45 nm. The specific surface area is 55 to 70 m2/g. The iodine adsorption value is 60 to 80 gI2/kg. Acetylene carbon black has a high purity, with carbon content greater than 99.5%, hydrogen content less than 0.1%, and oxygen content between 0.07% and 0.26%. The pH value is 5 to 7. It has a low resistivity, offering excellent conductivity, thermal conductivity, and resistance to static effects.