oxidized lignin cross-linked o-carboxymethyl chitosan /aminosilane modified ldh for enhanced tetracycline removal

Alkyl-lignin and o-carboxymethyl chitosan (o-cmc) are biodegradable polymers, potentially applied as an antibiotic adsorbent. however, hydrogels prepared from these natural polymers have very low durability even in weak acids. for improving the stability, a novel dual-crosslinked nanocomposite hydrogel (dcnh; imine bond and nanoparticle crosslinking) was prepared by combination of aminosilane modified mg-al ldh (aldh) , oxidized alkyl-lignin (oxi-lignin) and o-cmc. oxidation of lignin was performed with sodium periodate to prepare lignin dialdehyde (ld) and used as crosslinking agent. the ftir peaks indicated the cross-linking reaction of the active aldehyde of ld and the amin groups of carboxymethyl chitosan (cmc) and of aldh. the nanocomposite adsorbent shows a stable adsorption and resistance under acid. the nanocomposite adsorbent was stable under hcl 1 m. the thermos-stability of dcnh samples is also performed with of dta-tga. the dcnh adsorbent was stable up to 600°c. the hydrogel can be used as an adsorbent of tetracycline antibiotic (tc) in water. the optimum ph for adsorption of tc was reached at ph 5 with 98.3% efficiency and adsorption capacity of 65.51 mg/g.