A system that combines electrochemical oxidation and membrane microfiltration could improve the removal of microscopic plastic particles present in water.

Micro- and nanoplastic pollution is one of the most concerning emerging environmental challenges for ecosystems and human health. Various international and European official organizations (UN, European Commission, EEA, ECHA, WHO, FAO) have published assessments of their environmental incidence and potential impact on human health. For instance, the European Chemicals Agency (ECHA, 2021) estimated that 176,000 tonnes of unintentionally generated microplastics are released annually into European surface waters as a result of the abrasion and wear of plastic products. In addition, another 42,000 tonnes of microplastics intentionally added to products are released into the environment each year.

A new scientific study involving the Electrochemical Processes and Photoactivated Processes units at IMDEA Energy, in collaboration with Rey Juan Carlos University (URJC) under the European project HYSOLCHEM (FET-Open), proposes an innovative technology capable of effectively removing microscopic polyethylene particles—one of the most widely used plastics—present in water.

The research explores, for the first time, the combination of electrochemical anodic oxidation with membrane microfiltration to remove micro- and nanoplastics in aquatic systems.

Micro- and nanoplastics are tiny fragments resulting from the degradation of plastic products. Due to their extremely small size, they can pass through many conventional water treatment systems and accumulate in aquatic ecosystems, organisms, and food chains. Several studies have detected these particles in oceans, rivers, and even in human tissues.

An invisible but growing problem

In the proposed method, anodic oxidation generates highly reactive species capable of degrading or modifying plastic particles, thereby facilitating their subsequent removal through filtration. Integration with membrane microfiltration allows the transformed particles to be retained, increasing the overall efficiency of the process. This combined approach aims to overcome the limitations of traditional water treatment technologies, which often struggle to capture particles of nanometric size.

According to the researchers, the development of integrated electrochemical processes could enable more efficient and scalable water treatment systems capable of addressing one of the most difficult emerging contaminants to remove.

The combination of electrochemical oxidation and membrane filtration thus opens new perspectives for the design of advanced purification technologies. If optimized at pilot and industrial scale, this approach could help improve drinking water quality and reduce the environmental impact of microplastics.