Oxygen-rich hyper-cross-linked polymers with hierarchical porosity for aniline adsorption

Herein oxygen-rich hyper-cross-linked polymers with hierarchical porosity were developed via two continuous Friedel-Crafts reactions. Their aniline adsorption was evaluated from aqueous solution. It indicated that the first Friedel-Crafts reaction introduced plentiful oxygen (O) on the polymers with the O content of 12.53 wt%. The second Friedel-Crafts reaction produced predominated micropores with micropore area over the Brunauer-Emmett-Teller (BET) surface area of 56.8%, the hierarchical porosity including micropores, mesopores, and macropores were characteristic for the as-fabricated polymers. The aniline adsorption was largely improved on the synthesized polymers, in which the maximum capacity was 178.4 mg/g at 303 K as the introduced O and the manufactured micropores were greatly beneficial for the adsorption. The Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy demonstrated that the introduced O as a functional of the C O, C O, and O H groups strongly interacted with aniline. More importantly, 80 min was sufficient to reach the equilibrium, 0.6 g the polymers made the aniline solution (<40 mg/L) meet the discharge requirement of Chinese environmental protection authorities (<5 mg/L).