Adsorption property and kinetic studies of activated carbon fibers prepared from tissues by CO2 activation

Well-developed micro and mesoporous activated carbon fibers (ACFs) with fiber structure were prepared from tissue by CO2 activation. The XRD patterns and Raman spectrum indicated ACFs had a graphitic and amorphous structure. The SEM results indicated that the sample exhibited fiber structure with lots of mesoporous, with an average pore size of 2-5 nm. The specific surface area of 1517 m2 /g, micro surface area of 412.9 m2 /g, and total pore volume of 1.194 cm3 /g were obtained at 900°C with CO2 activation for 2 hours. ACFs showed relatively high methylene blue adsorption properties with an equilibrium adsorption capacity of 526 mg/g. The kinetic model of the Pseudo-second-order equation was more suitable for MB adsorption than the Pseudo-first-order equation and Intraparticle diffusion kinetics, with a high correlation coefficient value (R>0.999). The present research provided a new idea of bionics for the manufacture of ACFs and brought forward a creative prospect for achieving energy-related CO2 emissions to net-zero and mitigating global warming.