Study on the ion-exchange properties of the activated carbon black nanoparticles of ACBNPs20_17 code using sodium hydroxide solution

Abstract

Ion-exchange properties of the fabricated activated carbon black nanoparticles of ACBNPs20-17 code have been properly studied using several various concentrations of 0.001, 0.003, 0.005, 0.007 and 0.009 M sodium hydroxide (NaOH) solutions. The study was performed by mean of measuring both hydroxyl anions (OH-) quantity and electrical conductivity of the NaOH solution before and after it flowed down through the ACBNPs20-17 material at 1 drop per second flow rate due to gravitation force for four cycle's time. The study was aiming to correlate between the properties of anion-exchange and capability of adsorption of the ACBNPs20-17 material compared to that of the pristine carbon black (CB) powder. This research recorded that there was a competition between hydroxyl anion-exchange and hydroxyl anion adsorption. It was clearly known just the concentration of 9 mM NaOH provided hydroxyl anion-exchange on both ACBNPs20-17 material and CB, whereas the lesser concentrations of 1, 3, 5 and 7 mM NaOH provided hydroxyl anion adsorption rather than anion-exchange. In this case, anion-exchange capacity of the ACBNPs20-17 material was higher than that of the pristine CB materials. Ultimately, it can be concluded that adsorption process happened first before anion-exchange process, and the later would precede when the concentration of NaOH solution feed higher enough, i.e. about equal or more than 0.009 M.