Efficient removal of dyes by a novel magnetic Fe3O4/ZnCr-layered double hydroxide adsorbent from heavy metal wastewater

► Fe3O4/ZnCr-layered double hydroxide adsorbent was produced from wastewater. ► RSM was successfully applied to the optimization of the preparation conditions. ► The maximum adsorption capacity of MO was found to be 240.16 mg/g. ► The MO adsorption mechanism on MFLA was certified. ► MFLA could be recycled after catalytic regeneration by the oxidation technology.