Preparation and characterisation of activated carbon from palm kernel shell by physical activation with steam

Granular activated carbon was produced from palm kernel shell using commercial scale carbonisation and activation systems. Carbonisation was carried out using kiln earth system while activation took place in a commercial scale rotary kiln. Steam was used as oxidising agent during activation process with temperature range from 900oC to 1000oC. Palm kernel shell activated carbon was characterised based on proximate and ultimate analyses, thermal stability, chemical functional groups, and surface area. Scanning electron microscope was used to determine the surface morphology of the carbon products. It was found that palm kernel shell is a suitable material to produce activated charcoal owing to its low ash content (2.3 wt %) but high in carbon and volatile content, 23 wt % and 61.7%, respectively. The maximum thermal stability was observed up to 700oC for palm kernel shell activated carbon and raw palm kernel shell but 600oC for palm kernel shell charcoal. The Brunauer-Emmett-Teller (BET) surface area of palm kernel shell activated carbon produced in this study is 607.76 m2 g-1 with 541.76 m2 g-1 micropore area; this is comparable to commercial activated carbon with BET surface area of 690.92 m2 g-1 with 469.08 m2 g-1 micropore area. From the adsorption experiment, palm kernel shell activated carbon could remove up to 80.7% of chemical oxygen demand with 8.83 mg g-1 adsorption capacity; this is comparable to the performance of commercial activated carbon available in the market. The results of this study proved that good quality activated carbon can be produced from palm kernel shell