Microplastics removal from natural surface water by coagulation process

The present study aimed to compare the efficiency of microplastic removal from natural surface water by coagulation with ferrous and aluminum sulfate in the presence and without the selected coagulant aids. Coagulation with Fe(II) and Al(III) sulfates at doses conventionally used for drinking water treatment (10 – 80 mg.L−1) was effective in polystyrene and polyvinyl chloride removal. Fe(II) salts showed up to 5 % efficiency higher in microplastic removal under the conditions of the experiment. The addition of the flocculating agent to support the aggregation of flocs allowed for the improvement of microplastic removal efficiency at the same dose of up to 10 %. Based on the results, flocculating agents are recommended for microplastic removal. Coagulation without flocculating agent amendment is enough to remove most microplastics if filtration is applicable.