Comparison of different activation methods for activated carbon produced using various methods from Phyllostachys edulis (bamboo moso) biomass

Plant biomass is becoming an increasingly viable alternative for producing activated carbons, compared to fossil sources. The most commonly used biomass sources include agricultural waste, vegetable biomass from the food industry, and biomass waste from the processing of woody materials. Among the biomass that has received attention is bamboo. This grass it is capable of storing large quantities of CO2 during its growth phase, and appears to be a renewable resource with a fast-growing rate that can be utilized as a starting biomass for the production of activated carbon. There are multiple methodologies in the literature for preparing activated carbons from biomass, but each of these methodologies leads to the formation of materials with distinct properties. For this reason, three different pre-activation (two chemical and one physical method) and activation methods (using different KOH ratios and activation temperature) of preparing active carbons were applied and compared with each other. The materials obtained were compared using scanning electron microscopy to assess morphology, infrared spectroscopy to evaluate the surface functional groups, thermogravimetric analysis, and Raman spectroscopy to determine the water contenent and degree of graphitisation of the materials. Finally, through physisorption of nitrogen at 77 K it was possible to determine the surface area and porous volume. The materials produced demonstrated that bamboo can serve as a biomass for the preparation of activated carbons, and that different methodologies lead to the production of materials with different functionalities and chemical-physical properties.