Citric acid-incorporated cellulose nanofibrous mats as food materials-based biosorbent for removal of hexavalent chromium from aqueous solutions.

Nanoscale biomass materials derived from food materials (e.g., polysaccharide, protein, organic acid) have shown great promises with regard to the removal of heavy metal in wastewater treatment. Herein, we have developed the functionalized cellulose nanofibrous mats as an environment-friendly biosorbent via electrospinning of cellulose acetate solution, followed by deacetylation and citric acid modification. The morphology, chemical, and structural characterizations of the cellulose nanofibrous mats were examined by SEM, FTIR, XRD, DSC, and TGA to follow each stage of the preparation process of them. The effect of the incorporation of citric acid in the cellulose molecule on the adsorption performance of the naofibrous mats was then studied by batch adsorption experiments. Consequently, citric acid-modified cellulose nanofibrous mats with reasonably high absorption selectivity for Cr(VI) can be readily prepared. Results from this study may provide a promising food materials-based biosorbent that can be used as an emerging material in wastewater treatment application.