Superabsorbent Cellulose–Clay Nanocomposite Hydrogels for Highly Efficient Removal of Dye in Water

Toxic dyes have threatened human health through the consumption of polluted water, so removal of dyes from wastewater has become a hot topic in both academic and industrial fields. Herein, we reported a kind of cellulose–clay hydrogel with superabsorbent properties, superior mechanical performance, and high dye removal efficiency. The main strategy for the preparation of superabsorbent hydrogels was chemical cross-linking of cellulose, carboxymethyl cellulose (CMC), and the intercalated clay in NaOH/urea aqueous solution. The as-prepared hydrogels exhibited high absorption capacity for methylene blue (MB) solution through a spontaneous physic-sorption process which fitted well with pseudo-second-order and Langmuir isotherm models. The maximum removal efficiencies of hydrogel samples for MB solutions with concentrations of 10 mg L –1 and 100 mg L –1 were 96.6% and 98%, respectively. These results demonstrated that cellulose–clay nanocomposite hydrogels were effective adsorbents for removal of MB dyes, which would provide a new platform for dye decontamination.