Capture and sensing of anionic pollutants from aqueous environmental samples

Abstract

Contamination of water because of pollution is a large issue on a global scale; a problem which has led to the aim of this research -to examine methods for the removal of anionic pollutants from aqueous systems. Within wastewater systems, there are a large number of anionic pollutants that are of interest, however within this work only a few were examined, with a main focus on both phosphate and glyphosate. It is thought that the findings within this work could then be applied towards other pollutants as an appropriate starting point for further applications and research into a wider range of pollutants. A range of novel materials for the capture and sensing of anionic pollutants has been successfully demonstrated. The use of chitosan beads for the removal of phosphate from wastewater systems has been studied as a proof of concept with the ability to remove ~10% of the phosphate present in effluent waste water. The use of MIPs for removal of glyphosate and AMPA from water has been examined in significant detail and polymers have been synthesised with a maximum association constant of 107.2 µmol g-1 for glyphosate and 82.45 µmol g-1 for AMPA. Their application as a colorimetric sensor demonstrated a linear response up to a concentration of 2 mM. Finally, a range of novel squaramide based receptors have been examined for their ability to bind anions, which would provide a solid foundation for future work into their application. A series of novel cyclic squaramide receptors were developed that demonstrate a high affinity towards anions, with a potential application in fluoride sensors being explored due to a visible colour change from red to green in the presence of fluoride, while a second series of squaramide receptors containing a dopamine moiety were examined for a potential application in surface coatings.

Thesis embargoed until 31 July 2027

Date of Award	Jul 2022
Original language	English
Awarding Institution	Queen's University Belfast
Sponsors	Northern Ireland Department for the Economy
Supervisor	Panagiotis Manesiotis (Supervisor) & John McGrath (Supervisor)