Biomass polyamine-functionalized nanocellulose-loaded covalent organic framework to construct composite aerogels for highly efficient removal of Cr (VI) and methyl orange

Abstract

Heavy metal ions and organic dyes cause ecological pollution, which is a problem that needs to be solved urgently. In this study, a novel biomass polyamine-functionalized nanocellulose loaded-covalent organic framework (COF) successfully constructed a hybrid aerogel (TDB). Due to the synergistic effect of biomass polyamines and COF, a vast number of active sites are present on the surface of TDB aerogel. This made the TDB aerogel have the largest adsorption capacity (470.67 mg/g, 488.22 mg/g) and the highest removal efficiency (98.49 %, 99.51 %) for Cr (VI) or MO (methyl orange). In the binary pollutant system, TDB aerogel also showed excellent removal efficiency for Cr (VI) and MO (91.29 %, 82.84 %). The adsorption process and adsorption mechanism of TDB aerogel were analyzed by adsorption kinetics, adsorption isotherms, thermodynamics, FTIR, and XPS. Its crystalline structure also didn't change. Fixed-bed column adsorption experiments showed that TDB aerogel could effectively purify 4510 mL of wastewater that contained Cr (VI) or 4681 mL of wastewater that contained MO. Therefore, TDB aerogel can be considered a promising adsorbent for the treatment of heavy metal ions and organic dyes in wastewater.