Comparison of surface properties of wood biomass activated carbons and their application against rhodamine B and methylene blue dye

Chemical agents and activation atmosphere have a pretty good influence on the formation of activated carbons, surface characteristic, and its adsorption properties. In this experiment, the effect of activating agents (H3PO4, ZnCl2, KOH, and CaO) on Acacia mangium wood under nitrogen and carbon dioxide gas atmosphere were evaluated. The obtained activated carbons were characterized by percent burn-off, field emission scanning electron microscopy (FESEM), energy dispersive x-ray spectroscopy (EDX), image analysis, textural properties, Fourier transform infrared spectroscopy (FTIR), powder x-ray diffraction (XRD), thermogravimetric analysis (TGA), proton adsorption capacity, and pHzpc. The results revealed that the chemical activation increased the yield and oxygen-free atmosphere created by nitrogen gas was more efficient in producing significant surface area, and large pore volume activated carbons with a pore size in the range of 2 nm–50 nm. Among the activating agents, the H3PO4 was observed to be most appropriate in the presence of N2 activation atmosphere for the production of the large surface area (BET surface area, 1161.29 m2/g) activated carbons (AMH1) from Acacia mangium wood. The adsorption capacity of AMH1 against rhodamine B and methylene blue were found to be 76.66 mg/g and 159.89 mg/g, respectively.