Preparation and characterization of functionally antibacterial multi-layer lignin core-shell structure material with adsorption and high efficiency of photocatalysis for Cr(Ⅵ)

Wastewater with chromium is a common heavy metal pollution in industrial pollution, affecting health of human seriously, while adsorption and photocatalysis are efficient for Cr(Ⅵ) removal. The multi-layer lignin core-shell structure materials were prepared with kraft lignin/polydopamine core-shell structure material, using non-covalent bonding to induce the in-situ induction of TiO 2 . The hydroxyl group of kraft lignin and the amino group of polydopamine provided abundant adsorption active sites with adsorption capacity being 299 mg/g at pH of 2. The adsorption process conformed to the Freundlich isotherm model and the pseudo-second-order kinetic model. The removal rate of Cr(Ⅵ) reached more than 99.9 % within 10 min under simulated solar light with influence of adsorption and photocatalysis. The multi-layer lignin core-shell structure materials presented excellent antibacterial activity, with the inhibition rate against S.aureus and E.coli being 40 % under dark conditions and 99 % under simulated solar light because h + or ·OH producing by TiO 2 . The antibacterial multi-layer lignin core-shell structure materials showed good universality in water pollution treatment.