Green recyclable chitosan/carboxymethyl cellulose/sodium alginate magnetic double-network composite hydrogels for adsorption of MB and Cu2+

In this work, Fe 3 O 4 magnetic particles were in-situ grown on the surface of Montmorillonite (MTT) via co-precipitation method, and a green, recyclable chitosan (CS)/carboxymethyl cellulose (CMC)/sodium alginate (SA)/MMT-Fe 3 O 4 double network (DN) hydrogel (C-M-SD/MMT-Fe 3 O 4 ) was successfully synthesized. The magnetization of MMT-Fe 3 O 4 addition improved the maximum compressive strength of CS/CMC/SA double network hydrogel (C-M-SD), reaching 17.13 kPa. The adsorption capacities of the magnetized DN hydrogel for methylene blue (MB) and Cu 2+ were 224.49 mg/g and 121.15 mg/g, respectively. Moreover, cytotoxicity tests using CCK8 solution showed that the cell activity was >80 % after 24 h culture in the prepared hydrogel extracts, which demonstrated that the prepared hydrogel adsorbent did not release any toxic substances into the water source throughout the adsorption process . It can be concluded from the Vibrating Sample Magnetometer (VSM) that the saturation magnetization of the prepared magnetic double-network hydrogel reaches 15 emu/g and the coercivity is 0, showing the superparamagnetism . The synthesized C-M-SD/MMT-Fe 3 O 4 hydrogel possesses excellent mechanical properties, natural degradability, recyclability and biocompatibility, making it an ideal candidate for wastewater treatment applications.