Role of KCl in activation mechanisms of KOH-chemically activated high surface area carbons

Abstract

Activated carbons from different precursors have been synthetized using KOH and mixtures of KOH and KCl as activating agents. The results revealed an increase of surface area and yield of activation related with KCl addition in all the samples. Thermodynamic and mass spectrometry studies reveal that KCl do not act as an activating agent, but promotes the solubilisation of secondary products of the reactions such as carbonates, enhancing the contact of KOH and carbon particles, therefore increasing the efficiency of the activation. Based on mass spectroscopy results, combined with thermodynamic calculations, we proposed four reactions as the most likely responsible for the pore development during activation.