Influence of activation on the pore structure of adsorbents obtained from coal–alkali mixtures

Abstract

The activation of carbon sorbents in CO₂ is investigated. The sorbents are produced by the thermolysis of naturally oxidized SS coal steeped in potassium hydroxide, with an alkali/coal ratio R_KOH = 0.01 and 0.05 g/g. The influence of CO₂ activation on the texture of the sorbents obtained is established. After 10-min activation, the increase in specific surface area of the sorbents is a maximum (about 100%). Longer activation increases the loss of material. The pore volume formed on activation is proportional to the proportion of carbon-bearing material removed. The volume of adsorbing pores formed in the sorbents is greatest when the loss of material is 25–35%.