Investigation of Activation Time on Pore Size Distribution of Activated Carbon Determined with Different Methods

Document Type: Original Research Paper


Chemical Engineering Department, University of Shahid Bahonar, Kerman, I.R. Iran


Three activated carbons are synthesized in a rotary reactor at different activation times. The adsorption isotherms of the samples are measured The pore size distribution of the samples is determined using combined Saito and Foley method, BJH method. An average potential function has been determined inside the cylindrical pores. The effect of activation time on the pore size distribution samples was investigated. In the micropore size range, as the reaction started, the SF method show the initial micropore was generated. As the activation reaction progress, the micropore volume is developed and widened and therefore area under the PSD curve is increased. Improving the reaction, the pore overlapping was carried out and this occurrence causes decreasing in micropore volume. In the mesopore size range, mesopore volume is increased as the reaction progress. It is acceptable because both developing and overlapping of pores causes improvement of mesopore (and macropore) volume


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