1. Prophase
Early deashing refers to deashing the raw coal before the production of activated carbon, and treating the raw coal with high ash content to ultra pure coal that meets the requirements to directly produce low ash carbon. The removal of inorganic mineral components with catalytic activity will reduce the reactivity of treated coal and reduce the gas-solid reaction rate. High quality activated carbon with highly developed micropores and large pore volume can be prepared.
However, the disadvantage of the pre-treatment process is that the treatment capacity is large, and more deashing agents are required if the chemical law is used. In addition, minerals in the carbonization process is a material that promotes the transformation of carbonized materials to high specific surface area carbon. Minerals are basically removed before carbonization, which is still unfavorable to the production of activated carbon.
2. Metaphase
The medium-term treatment method refers to deashing the semi-finished carbonized material, and then activating it to obtain activated carbon.
3. Later period
Post treatment is deashing of activated carbon, which is generally deashing with dilute acid pickling. This is a widely used process in the industrial production of activated carbon. Proper treatment process can indeed reduce the ash content of activated carbon by 25% - 40%. However, acid pickling and deashing of activated carbon will usually reduce the specific surface area of finished carbon and change the pore size distribution and porosity of carbon.
