Electrified Membranes for Water Purification, and Membrane Fouling Control

Abstract

Microplastics and nanoplastics (MNPs) are plastic particles of sizes less than 5 mm and 100 nm respectively, found in a wide range of water sources such as oceans, rivers, tap water, and in treatment plants. They can persist in water for hundreds of years and their presence and accumulation in water bodies and treatment plants can potentially harm aquatic as well as human life. Membrane technology, such as ultrafiltration (UF), can play a key role in the removal, but fouling can be a major concern. Electrified membrane technology uses a low voltage electric potential to enhance the separation process, and has the potential to be energy efficient, versatile, cost-effective, and easy to maintain, but its capability and potential for removing MNPs has yet to be fully developed. MXenes have high surface area, good mechanical properties, high hydrophilicity, low density, and ability to withstand harsh conditions, making it attractive for water treatment. Their high electrical conductivity also gives it potential in electrified membranes. Ti3C2Tx and Nb2CTx are to date, the only two types of MXenes explored for water treatment. Hence, this work suggests a novel hybrid electrocoagulation-membrane filtration system by utilizing the unique properties of MXenes, particularly Ti3C2Tx and Nb2CTx, and their integration into an electrified membrane system.

We first present a detailed exploration of the innovative process and proof-of-concept, from material selection and membrane fabrication to the innovative use of machine learning models for performance prediction. The findings underscore the efficacy of MXene electrified membrane process in improving water filtration efficiency. Building on the theoretical groundwork, the performance of composite MXene-integrated electrified membranes is investigated. Through a series of tests and characterizations, the significant advantages of incorporating Ti3C2Tx and Nb2CTx with PES/SPES for enhanced MNP fouling mitigation and overall removal efficiency is proved. The experimental results also confirm the proposed hybrid technology based on electrified MXene membranes, offering enhanced MNP separation by applying electric field. Finally, the scalability study of the MXene-based electrified membrane technology evaluates the practical implications of the research findings.

Date of Award	9 Dec 2024
Original language	American English
Supervisor	SHADI Hasan (Supervisor)