Fig. 1. Schematic illustration of purification of microplastics (0.5–125 μm) suspension in water. Polystyrene (PS)/polyethylene (PE) beads are used as a model of the microplastics. The surface of the microplastics is treated with chitosan and tannic acid to form surface phenolic microplastics. Then, Fe3+ triggers the coagulation of the microplastics by Fe3+-phenolic coordinate bonds. The coagulated microplastics are filtered for the removal of microplastics, results in purified water.
