Nanopore structures, surface morphology, and adsorption capacity of tabah bamboo-activated carbons

The adsorption capacity of activated carbon is largely determined by its pore structure characteristics such as its surface area, pore volume, and pore size distribution. The purpose of this study is to investigate the pore structures and surface morphology characteristics of tabah bamboo (Gigantochloa nigrociliata) activated carbons that carburized up to a temperature of 800 °C over 2 h and physically activated at 820 °C under nitrogen flow and different activation times (50, 100, and 150 min). The activated carbons produced are expressed as 50M-FA, 100M-FA, and 150M-FA for the activation times of 50, 100, and 150 min, respectively. Pore structures and morphology characterizations were carried out by applying a nitrogen adsorption isotherm at 77.3 K and scanning electron microscope (SEM), respectively. The results reveal that the surface area, pore volume, and N2 adsorption capacity increased with increasing activation time and reached a peak at 150 min with a surface area of 210.200 m2/g, a pore volume of 0.090 cm3/g, and N2 adsorption capacity of 81.645 cm3/g. Surface morphologies showed that pore structures in micropore and mesopore sizes have been formed on the surface of activated carbons. The pores size distribution types of 50M-FA, 100M-FA, and 150M-FA were monomodal, multimodal, and bimodal distributions, respectively. The most adsorption occurs in the micropores area (0.248–2 nm) and mesopores area (2.042–14.838 nm) for 100M-FA, meanwhile, almost all adsorption occurs in the mesopores area of 2–47.581 nm and 2.459–47.581 nm for 50M-FA and 150M-FA respectively.