Removal of Micro and Nano Plastics from Waters by Foam Fractionation and Froth Flotation

Micro and nanoplastics (MNPs) enter the ecosystems due to coastal, industrial, and domestic pathways, and are a threat to the environment. Developing a reliable and fast MNP synthesis method is vital for conducting quality experiments to understand the fate, behaviour, and impact of these plastics in the environment. Unfortunately, the current reference materials that are available for instrument calibration purposes do not accurately mimic particles produced in nature. The initial scope of the research is on finding and developing a suitable methodology for producing synthetic MNPs in the laboratory environment. One way for micro and nanoplastics to enter the environment is through wastewater treatment plants. The by-product of wastewater treatment is a mixture of water and organic materials which is then dumped directly into landfills. Unfortunately, during this process micro and nanoplastics that were present in the wastewater are also deposited into landfills and leach chemicals which eventually find their way back into the wastewater treatment systems. This closed-loop and cyclic process results in a continuous increase of MNPs loading into the wastewater treatment system. Unfortunately, there is a lack of comprehensive study on the removal efficiency of MNPs from the leachate treatment plants, hence a reliable and efficient separation process is necessary to decrease this load. Similarly, stormwater is considered a major land-based MNP source to the water bodies. Currently, there is no active system for stormwater treatment, and untreated stormwater feeds directly to creeks and rivers, depositing a large amount of plastic into the environment. This research aims to look at a suitable treatment process for stormwater.

Due to their low density and water-repelling properties, the foaming systems are seemingly low-cost treatment systems for the removal of MNPs from stormwater and landfill leachates. Although significant studies are available on microplastic removal through this technique, no clear explanation exists on the bubble-plastic particle adhesion and their transport in the foaming system. The overall aim of this research is to understand the application of foam flotation for the removal of micro and nano plastics from contaminated water systems and develop the experimental conditions to improve the flotation performance.

Research Outputs

Buckley, T., Karanam, K., Xu, X., Shukla, P., Firouzi, M. and Rudolph, V., 2022. Effect of mono-and di-valent cations on PFAS removal from water using foam fractionation–A modelling and experimental study. Separation and Purification Technology286, p.120508.

Buckley, T., Karanam, K., Han, H., Vo, H.N.P., Shukla, P., Firouzi, M. and Rudolph, V., 2023. Effect of different co-foaming agents on PFAS removal from the environment by foam fractionation. Water Research230, p.119532.

Buckley, T., Vuong, T., Karanam, K., Vo, P.H., Shukla, P., Firouzi, M. and Rudolph, V., 2023. Using foam fractionation to estimate PFAS air-water interface adsorption behaviour at ng/L and µg/L concentrations. Water Research239, p.120028.


Project members

Kavitha Karanam

PhD Candidate

Prof Kevin Thomas

QAEHS Director
and Theme Leader, Environmental Health Toxicology

Dr Elvis Dartey Okoffo

Research Fellow