Adsorption of polyethylene microplastics using Fe3O4 nanoparticles from Tulungagung ilmenite sand

Plastic waste pollution in rivers is an environmental problem caused by the lack of public awareness and concern about throwing waste in waterways. One of the consequences is that plastic waste is difficult to degrade in waters for a long time until microplastics are formed. The type of microplastic waste often found in river waters comes from plastic-based beverage packaging, which is generally polyethylene. The presence of microplastic waste can endanger living things and their environment. Therefore, handling and controlling microplastics in the environment is necessary and urgent. The adsorption method is more appropriate and efficient regarding time, implementation, and cost, and it is environmentally friendly in eliminating microplastics. The material that has the potential to adsorb microplastics is Fe3O4 nanoparticles. This material can be obtained by extracting Tulungagung ilmenite sand through coprecipitation. This simple, inexpensive method uses room temperature and makes it easier to control the size of sample particles. The synthesized Fe3O4 nanoparticles with 15, 17, 19, 21, and 23 mg/ml concentrations were tested for 150 minutes in artificial seawater and mineral water dissolved with low-density polyethylene. The results showed that the removal of polyethylene microplastics in artificial seawater was more efficient than in mineral water, with the highest adsorption efficiency in artificial seawater reaching 97.5% and in mineral water reaching 90.5% at a concentration of Fe3O4 nanoparticles of 23 mg/ml. Thus, Fe3O4 nanoparticles from Tulungagung ilmenite sand can be candidates for microplastic removal applications with a simple technique and have specific application prospects.