High adsorptivity and recycling performance activated carbon fibers for Cu(II) adsorption.

In order to develop adsorbent materials with high Cu(II) adsorptivity and renewable recycling for Cu(II), nitric acid oxidation process is optimized and ameliorated by microwave and sonication to obtain an efficient modification and regeneration processes. Microwave-assisted nitric acid oxidation process has the most significant enhancement effect to the Cu(II) adsorptivity of activated carbon fiber felts (ACFFs), which can reach 23.13 mg/g and 4.55 times of pristine felts. It is due to this process can greatly increase the ultramicropore volume and polar oxygen-containing groups. In addition, sonication-assisted-pickling regeneration process achieves efficient regenerations and enhancements of Cu(II) adsorptivity for ACFFs. The Cu(II) adsorptivity and regeneration rate of ACFFs are still up at 25.51 mg/g and 379.59% after five times recycling by the process of sonication-assisted pickling regeneration process.