The activation processes of activated carbon include gas activation, chemical activation, and chemical physical activation.
So what are the differences between these three activation methods?
The three activation methods each have their own characteristics, requirements for raw materials, and the properties and applications of the produced activated carbon are also different.
The chemical activation method is generally carried out under acidic conditions, which can cause corrosion to production equipment. At the same time, due to improper treatment of wastewater and exhaust gas generated during the production process, it can cause significant environmental pollution. Therefore, the material of the chemical activation method equipment almost always requires corrosion resistance. The manufacturing equipment is expensive, the manufacturing process is complex, and it is difficult to produce in large quantities. There are many production and device engineering issues, and the production process is also difficult to strictly control.
The chemical activation method is generally carried out under acidic conditions, which can cause corrosion to production equipment. At the same time, due to improper treatment of wastewater and exhaust gas generated during the production process, it can cause significant environmental pollution. Therefore, the material of the chemical activation method equipment almost always requires corrosion resistance. The manufacturing equipment is expensive, the manufacturing process is complex, and it is difficult to produce in large quantities. There are many production and device engineering issues, and the production process is also difficult to strictly control.
The gas activation method is carried out at high temperatures, and the waste gas generated during the production process is discharged in the form of carbon dioxide and water vapor. At the same time, there is basically no wastewater generated during the production process, so the pollution to the environment is minimal. The pore size range of activated carbon produced by gas activation method is relatively large, and the product has a wide range of applications. Due to the need to first carbonize the raw materials, gas activation method is basically suitable for the production process of activated carbon from all carbon containing materials, especially for the production of activated carbon from anthracite and bituminous coal. Gas activation method is not only very suitable, but also has a high product yield. Activated carbon is produced using gas activation method with anthracite and bituminous coal as raw materials, and the yield of activated carbon products (relative to the raw materials) is generally as high as 30% to 50%. At present, domestic and foreign manufacturers producing activated carbon from anthracite, bituminous coal, and exposed coal generally use gas activation method.
https://www.naturecarbon.com/high-performance-activated-carbon/koh-impregnated-activated-carbon.html
