Pore Structure and Adsorption Properties of Coal-Based Activated Carbons Prepared by Thermal-Shock Alkaline Activation

The adsorption of phenol, 4-chlorophenol, methylene blue, and Pb(II) by coal-based activated carbons prepared by a thermal shock alkaline activation was studied for the first time. The adsorption kinetics and isotherms were measured and compared with those of carbons obtained by a temperature-programmed activation. The adsorption rate was determined to be limited by the interaction of adsorbate with surface centers, and not by the diffusion into pores. Thermal shock increases adsorption rates by 1.18 – 3.16 times and equilibrium capacities by 1.13 – 2.08 times, depending on the adsorbate and the coal type. The carbons prepared by thermal shock were found to be more effective adsorbents for water purification from ecotoxicants.