Water Resources Research Act Program

Details for Project ID 2017RI127B

Water Purification via Hydrogels with Voltage-Controlled Electrodynamic Properties

Institute: Rhode Island
Year Established: 2017 Start Date: 2017-03-01 End Date: 2018-02-28
Total Federal Funds: $22,067 Total Non-Federal Funds: $60,135

Principal Investigators: Samantha Meenach, Stephen Kennedy

Project Summary: Rhode Island’s industrial and commercial bases present high potentials for water contamination. Accordingly, many municipalities have strict restrictions on the types and amount of contaminants that can be discharged to wastewater treatment facilities. These include restrictions on heavy metal ions, organics, metals, solvents, and oils. Therefore, there is a strong demand for new water pre-treatment strategies. While hydrogel-based water treatment strategies are promising in that these materials are capable of retaining and transporting high concentrations of water-carried contaminants, there are a number of aspects requiring improvement for wastewater treatment applications. Namely, hydrogel-based strategies for removing specific contaminants must be developed. This proposal presents a novel hydrogel material that will be capable of presenting variable electrical charge in a voltage-controlled manner for the sequestration and removal of model contaminants. We believe that the ability to flexibly modulate the hydrogel’s charge in real time will enable selective sequestration and release of specific contaminants. The objectives of this project are to develop a voltage-responsive hydrogel system and demonstrate its ability to sequester and release contaminants with specific charge profiles. This hydrogel system will be composed of a neutral poly(acrylamide) (p(AAm)) matrix that is covalently cross-linked with poly(ethylene glycol) dimethacrylate (PEGDM). The poly(AAm) matrix will entrap a network of PEDOT polymers that are capable of carrying charge in response to applied voltages. For the added ability to sequester and release contaminants, the hydrogel system will be cryopolymerized to provide it with a highly porous structure. We hypothesize that the ability to dynamically present various polymeric charges within a porous hydrogel structure will allow us to selectively sequester, store, and release specific wastewater contaminants. The proposed studies leverage the PIs’ unique combined backgrounds in hydrogel-based materials, polymer chemistry, and electromagnetics, thus making them particularly well suited to execute the work. To test our hypothesis and develop the proposed system, we propose to complete the following goals: Goal 1: To determine how the structure and polymeric charge of hydrogels influence their ability to sequester, store, and be cleansed of various water impurities. Goal 2: To design a hydrogel system capable of exhibiting a variable polymeric charge as initiated by an applied voltage. Goal 3: To evaluate how the polarity, intensity, and temporal variation of the applied voltage influence the ability to selectively sequester, store, and release various impurities to/from the hydrogel system. The proposed work will result in a hydrogel-based system that is highly adaptable to a wide range of potential contaminants while being simple and inexpensive to produce, straightforward to implement, and reusable. Such a flexible and dynamic water treatment system will not only be highly beneficial to the state of Rhode Island and its surrounding industrial areas but to industries and municipalities worldwide, owing to the flexibility, tunability, and specificity for certain wastewater contaminants.