ICRA patents new graphene sponge technology that removes persistent pollutants from water at low cost and without chemicals
The system created by the ICRA team makes it possible to remove PFASs and other emerging pollutants from the aquatic environment at a cost between 60 and 120 times cheaper and in a sustainable way, without using chemical reagents.
The research is led by ICRA researcher Jelena Radjenović, who today will receive the National Research Award for Young Talent 2021 from the Government of Catalonia.
The development of nanostructured graphene sponge electrodes for water treatment is the new technology patented by a team of researchers at the Catalan Institute for Water Research (ICRA), which uses no chemicals and is 60-120 times cheaper than other electrochemical processes. These nanotechnological elements allow, for the first time, an electrochemical treatment of persistent water pollutants without producing toxic compounds from chloride oxidation, which is the main limitation of existing electrode materials.
The research is part of the European Electron4water project led by Jelena Radjenović, ICREA research professor at ICRA, who will be awarded today, Tuesday 7 June, with the National Research Award in Young Talent 2021, granted by the Government of Catalonia and the Catalan Foundation for Research and Innovation (FCRI).
One of the main concerns worldwide is the security of water supply due to climate change and the presence of highly toxic and persistent substances such as perfluoroalkylated compounds (PFAS) in aquatic environments. "In the search for new technologies to remove PFASs and other emerging pollutants, electrochemical processes offer many advantages over other advanced oxidation processes. It uses only current without adding chemical reagents and at the same time has the ability to treat water from any source, from tap water to industrial effluents, or the fact that it breaks carbon-fluorine bonds, C-F, one of the strongest chemical bonds, overcoming one of the biggest obstacles presented in advanced oxidation processes," explains Jelena Radjenović. However, the mass application of these processes has been limited, in part, by the high cost of the electrodes, ranging from €3,000 to €6,000 per m2 and by the generation of highly toxic chlorinated by-products due to the oxidation of chloride during treatment, an ion found in all waters.
These limitations disappear with the advances made by the ICRA team. The graphene sponges developed offer significant advantages over the materials currently used in commercial electrodes. The cost of producing this material is much lower: less than €50 per m2, which makes it highly attractive for large-scale application. In addition, the synthesis process is easily scalable and allows functionalisation of the sponge to attract and degrade certain groups of organic pollutants, thus increasing the efficiency of the process in complex matrices.
For Jelena Radjenović, "New electrochemical systems are the big revolution in water management and treatment (also called water 4.0). It is a breakthrough towards the implementation of decentralised water treatment instead of the current system that has been in place for 100 years. In the future, for example, we will have water treatment and reuse directly in buildings or business parks, instead of having only the wastewater and drinking water system of WWTPs or DWTPs. And it will be able to adapt to population growth or supply more remote areas".
In this sense, Jelena insisted on recalling the advantages of the electrochemical system: "They work only with current and can even be easily coupled to solar panels. They do not require the addition of chemical reagents and there are no production, storage, transport and handling costs, they are small in size (they have a modular design) and can be easily automated.