Efficient removal and recycle of acid blue 93 dye from aqueous solution by acrolein crosslinked chitosan hydrogel

In this study, we developed a novel chitosan-based adsorbent with low cost, high adsorption capacity and marvelous reusability. The adsorbent was prepared in one pot by crosslinking chitosan with acrolein, which was the first attempt to use acrolein as a crosslinking agent to achieve chitosan-based hydrogel (A/CS hydrogel). The A/CS hydrogel not only had the high swelling ratio as many as approximately 1300 times the dry hydrogel, but also has excellent adsorption property for the anion dye acid blue 93 (AB93). Under the optimal adsorption conditions, the adsorption capacity of the adsorbent on AB93 reached up to 1839 mg/g, which realized the ultra-high adsorption capacity. After 12 times of adsorption-desorption cycle, the adsorption rate of the adsorbent to AB93 was still about 90%, which revealed marvelous stability and reusability. The purpose of the present study was to provide a new choice of the elimination and recycle of AB93 and have potential for industrial application.