Biomass activated carbon derived from pine sawdust with steam bursting pretreatment; perfluorooctanoic acid and methylene blue adsorption.

• Steam bursting was used to pretreat sawdust to prepare activated carbon. • The carbon had specific surface area of 962 m2/g, micropore volume of 0.327 cm3/g. • The surface area and micropore volume decrease with the increase of pressure. • This carbon achieved a high adsorption capacity of 223 mg/g PFOA and 332 mg/g MB. Using waste biomass to prepare various products by environmentally benign processes is a good way to practice green and sustainable development. In this paper, high porosity and surface area biomass activated carbon was obtained by pyrolysis of pine sawdust without using any chemicals after steam bursting pretreatment. Under hydrothermal conditions at 160 ℃, the differences of steam bursting at 300, 500, or 700 psi pressures on the structure and surface chemical groups of the final activated carbons product were compared. The characterization showed that the specific surface areas and micropore volumes decreased with the increase of pressure, while the relative content of oxygen-containing functional groups changed slightly. The sample obtained following 300 psi pretreatment (HPB300) offered the highest BET surface area and pore volume, 962 m2/g and 0.526 cm3/g respectively, and which also achieved the highest adsorption amounts for both methylene blue (MB) and perfluorooctanoic acid (PFOA). [ABSTRACT FROM AUTHOR]