Plastics that we use daily don't exactly leave our lives when we are done with them. Our wastewater carries high concentrations of microplastics into the environment, harming marine life and sometimes finding their way back to humans, as this case of microplastics being revealed in the placentas of unborn babies can attest. While this is a serious issue, limited studies have been conducted on the degradation of microplastics.
A new technique, however, that uses diamonds and titanium seems to have the potential to remove microplastics in the wastewater directly at the source.
The researchers were able to decompose these plastic microfibers into naturally occurring molecules that are non-toxic to the ecosystem.
The research has been published in Environmental Pollution.
Wastewater treatment method
Microfibers from our clothes are one of the biggest contributors to this problem. Clothes made out of plastics release plastic microfibers when washed, entering the wastewater and making their way into our waterways if not removed. According to Professor Patrick Drogui, who led the study, there are currently no approved degradation methods to handle this problem during wastewater treatment.
The professor and his team devised a method that not only catches these fibers but also deconstructs them. "Using electrodes, we generate hydroxyl radicals (·OH) to attack microplastics, This process is environmentally friendly because it breaks them down into CO2 and water molecules, which are non-toxic to the ecosystem," he explained.
The researchers also stated that targeting the commercial laundry water before it arrives at the wastewater treatment is important since it gets mixed with water and becomes more difficult to degrade when diluted.
The laboratory tests
They conducted the experiments using boron-doped diamond and titanium electrodes on water that was artificially contaminated with polystyrene.
The results seem to be incredibly promising. After six hours, the water showed a degradation efficiency of 89 percent.
The researchers now want to move on to experiments on actual wastewater. The process will be more complicated, however, since water contains materials that can affect the degradation process.
While some drawbacks are present, such as using diamond being costly, the team hopes to overcome these problems and integrate this technique into commercial laundries in the future.