Production of activated carbon from bagasse and rice husk by a single-stage chemical activation method at low retention times

The production of activated carbon from bagasse and rice husk by a single-stage chemical activation method in short retention times (30–60 min) was examined in this study. The raw materials were subjected to a chemical pretreatment and were fed to the reactor in the form of a paste (75% moisture). Chemicals examined were ZnCl2, NaOH and H3PO4, for temperatures of 600, 700 and 800 °C. Of the three chemical reagents under evaluation only ZnCl2 produced activated carbons with high surface areas. BET surface areas for rice husk were up to 750 m2/g for 1:1 ZnCl2:rice husk ratio. BET surface areas for bagasse were up to 674 m2/g for 0.75:1 ZnCl2:bagasse ratio. Results were compared to regular two-stage physical activation methods.