Project Summary

Sustainable access to clean, safe drinking water has been a key concern in Ireland in recent years. Many drinking water treatment plants do not have the technical capacity to fully eliminate microbial contaminants such as Cryptosporidium parvum and E. coli or emerging micropollutants of concern, such as pharmaceuticals, personal care products (PPCPs) and hazardous organic pollutants (HOPs). In order to assure water quality, and future proof the potential for reclaimed water use for potable purposes, there is a need for a variety of drinking water (DW) treatment technologies that can remove both microbial and other micropollutants in the same system, particularly for small water supply schemes.

Arising from this identified need, the key output from this project is an innovative drinking water treatment system that can be used for small scale drinking water treatment. This technology is based on combining the adsorption properties of graphene, the biocidal properties of a graphene/copper composite and a modular filtration system that is suitable for drinking water treatment in small- and middle-scale group water schemes, where the small volume of DW supplied per day makes conventional technology less effective and more expensive. This modular, integrated system was tested and validated and shown to remove key pathogens associated with drinking water, eg E. coli and Cryptosporidum as well as PPCPs. Secondary outputs and discoveries include:

• Graphene and graphene oxide were shown to be not biocidal, despite reports in the literature to the contrary, while a combination of copper and graphene as a nanostructured composite was shown to be biocidal
• Positively and negatively charged ultrafiltration membranes with improved characteristics were fabricated using graphene oxide and graphene oxide-TiO2 composites
• Acid-Activated Alginate-Graphene Oxide adsorptive beads were fabricated which exhibited strong potential for use in
  removal of organic pollutants.
• Public awareness of the importance of treatment of contaminated drinking water supplies was created through a mini-symposium, international and national scientific meetings, website and publications in both peer reviewed
  journals, book chapters and industry publications.