The fabrication and arsenic removal performance of cellulose nanocrystal-containing absorbents based on the "bridge joint" effect of iron ions.

• The adsorbents were synthesized based on the "bridge joint" effect of iron ions. • The adsorbents are suitable for a wide pH range when removing As(III)/As(V). • The addition of Fe(II) can't promote the adsorption of As(III)/As(V). • The prepared CNC-PEI-Fe(III) expended the application of CNC. By using the "bridge joint" effect of iron ions, cellulose nanocrystal-containing high-performance adsorbents were synthesized via coprecipitation method, which enhanced the cross-linking action of cellulose nanocrystal and polyethyleneimine. The morphology, specific surface area, surface chemistry and chemical valence of the adsorbents were characterized by SEM, FTIR, BET and XPS. According to the results, the iron ions successfully connect the two dispersed polymers together, inducing a large number of O-Fe-O bonds and, providing more adsorption active sites for the removal of seriously polluted and high-toxicity As(III)/As(V). Furthermore, the arsenic removal performance of the adsorbents was studied, and the adsorption mechanism was revealed according to the spectral characteristics of the chemical components. Of note, the synthesized iron-containing adsorbents are suitable for a wide pH range, which may offer a new application for nanocellulose in the treatment of arsenic pollution. [ABSTRACT FROM AUTHOR]