Oxygen-Rich Activated Carbon Fibers with Exceptional Cu(II) Adsorptivity and Recycling Performance

Activated carbon fiber felts (ACFFs) have abundant micropores and excellent physical adsorption properties but have a lower adsorptivity for Cu(II). A novel reactivation process, which introduced sonication in the traditional chemical-activation process, was utilized to prepared oxygen-enriched ACFFs with high surface oxygen content, high specific surface area, and high Cu(II) adsorptivity. In addition, the sonication-assisted pickling regeneration process is researched to realize the cyclic utilization of oxygen-rich ACFFs. Ultimately, the oxygen content, specific surface area, and micropore volume of the oxygen-rich ACFFs can reach 24.21%, 2674.7 m2·g–1, and 0.9593 cm3·g–1 respectively. The Cu(II) adsorption value of oxygen-rich ACFFs can reach 35.24 mg·g–1, which is 6.94 times that of pristine felts. Its regeneration rate can always be greater than 100% after five adsorption–regeneration cycles by the sonication-assisted pickling regeneration process.