Preparation and characterization of spherical activated carbons from oil agglomerated bituminous coals for removing organic impurities from water

A new and simple method of producing of spherical activated carbons (SACs) from different bituminous coals, i.e.. gas coal, gas-coking coal and orthocoking coal. is presented. Coal agglomerates of spherical shape obtained by oil agglomeration using rapeseed oil and linseed oil, were subjected to carbonization and activation with steam at 850 degreesC. The SACs prepared from gas-coking coal (hvAb) agglomerates were characterized by the best developed Porous structure with surface area S-BET of about 800 m(2)/g and pore volume of 0.40 cm(3)/g. The adsorption capacity of the produced SACs was determined in terms of substituted phenolic compounds, The adsorption of 2-chlorophenol (OCP), 4-chlorophenol (PCP) and 4-nitrophenol (PNP) from aqueous solutions was Studied under a static conditions on the SAC prepared from gas-coking coal agglomerated using rapeseed oil. At high concentrations Of the Solute the adsorption behavior of OCP was found to be different in comparison to PCP and PNP. The adsorption of the two last phenolic Compounds on the selected SAC is very well described by Langmuir adsorption model. For OCP a two-stepped adsorption isotherm was obtained. The Langmuir isotherm equation fits very well only for the first stage of the OCP adsorption. (C) 2002 Elsevier Science Ltd. All rights reserved.