2D Materials-Enhanced Hydrogels for Membrane Water Purification

Abstract

In this work, sodium alginate-polyacrylic acid hydrogels were investigated as draw agents in forward osmosis. The hydrogels were synthesized using the chemical crosslinking method, which combined a crosslinker and an initiator. This work was carried out in 3 phases—the first phase was the synthesis, optimization, and characterization of sodium alginate-polyacrylic acid hydrogels. In this phase, different ratios between the crosslinker and the initiator were used, and the hydrogels were tested for water production. Furthermore, the H1 hydrogel showed the highest water draw performance, and it was selected for the next phase of experiments. The second phase involved incorporating 2D materials (i.e., graphene oxide, MXene, and MoS2) to investigate if these materials will enhance the hydrogels’ properties and their water production. The graphene oxide composite hydrogel showed the highest water performance and significant improvement in mechanical properties; hence graphene oxide was selected for the next set of experiments. The third phase involved optimizing the graphene oxide content within the hydrogels and using these hydrogels as draw agents in forward osmosis desalination of groundwater. In this phase, the hardness ions (i.e., Ca2+ and Mg2+) and salinity ions (Na+ ) were removed. This work lays a strong foundation for using 2D materials to enhance the properties of polymeric hydrogels used as draw agents in forward osmosis desalination.

Date of Award	2025
Original language	American English
Supervisor	Maryam Alshehhi (Supervisor)