Detoxifying water without solvents

Materials World magazine
9 Jul 2020

Researchers from Swansea University, UK, claim they have developed an environmentally friendly water treatment method that is solvent-free and scalable.

‘The harmful organic molecules are destroyed by a powerful oxidising agent, ozone, which is boosted by a catalyst,’ explains Richard Palmer, Professor at The Institute for Innovative Material, Processing and Numerical Technologies (IMPACT) at Swansea University. ‘Usually such catalysts are manufactured by chemical methods using solvents, which creates another problem – how to deal with the effluents from the manufacturing process?

‘The Swansea innovation is a newly invented machine that manufactures the catalyst by physical methods, involving no solvent, and therefore no effluent. The new technique is a step change in the approach to water treatment and other catalytic processes.’

To make the catalysts, which are clusters of silver atoms, a vacuum-based process is used. The machine, Matric Assembly Cluster Source (MACS), has tackled the previous problems of inadequate cluster production rate and the limited research on them. MACS scales up the intensity of the cluster beam to produce enough grammes of cluster powder for practical testing. Ozone is then added to the powder to destroy pollutant chemicals in water, in this case nitrophenol.

‘It is now possible to produce enough clusters for study at the test tube level, with the potential to then scale up further to the level of small batch manufacturing and beyond,’ notes Palmer.

‘The MACS approach to the nanoscale design of functional materials opens up completely new horizons across a wide range of disciplines - from physics and chemistry to biology and engineering. Thus, it has the power to enable radical advances in advanced technology – catalysts, biosensors, materials for renewable energy generation and storage.

‘It seems highly appropriate that the first practical demonstration of Swansea’s environmentally friendly manufacturing process concerns something we are all concerned about – clean water!’