Pilot-Scale Synthesis of Activated Carbons from Vetiver Roots and Sugar Cane Bagasse

Abstract

The main objective of this study was to produce, under pilot conditions, activated carbons (AC) from two different Caribbean by-products, specifically, sugarcane bagasse and vetiver roots. The produced activated carbons under both physical and chemical activation processes were characterised with respect to their texture and surface chemistry. The textural and chemical analyses showed that the nature of the precursor played a crucial role in determining the main characteristics of the activated carbon that was produced. Indeed, under the pilot production chemical activation conditions, bagasse-derived AC (“Bag-pilot”) showed the highest specific surface area (i.e. Brunauer, Emmett and Teller surface, SBET) with 1,030 m2/g compared to 555 m2/g for vetiver-derived AC (“Vet-pilot”). Porous texture analysis revealed that “Bag-pilot” developed more volume (0.807 cm3/g) than “Vet-pilot” (0.352 cm3/g), whereas “Vet-pilot” displayed more micropores (27 %). As for the surface chemistry, results showed that “Bag-pilot” contain more acidic and basic groups than “Vet-pilot” which makes it more interesting for adsorption purposes. The cost estimate of producing AC from vetiver roots in Haiti revealed that the chemically activated carbon presented the lowest cost at $1.17 per kg compared with 1.46$ per kg for physically activated carbon.