Grantee Research Project Results

Electrified titanate nanowire membrane for point-of-use water purification

EPA Grant Number: SU841125
Title: Electrified titanate nanowire membrane for point-of-use water purification
Investigators: Chen, Wensi
Institution: Texas A & M University
EPA Project Officer: Page, Angela
Phase: I
Project Period: March 1, 2025 through February 28, 2027
Project Amount: $75,000
RFA: 21st Annual P3 Awards: A National Student Design Competition Focusing on People, Prosperity, and the Planet Phase I (2024) RFA Text
Research Category: Drinking Water , Clean Water , Water Quality , Human Health , Water , P3 Awards , P3 Challenge Area - Safe and Sustainable Water Resources , P3 Challenge Area - Sustainable and Healthy Communities , Environment , Water Treatment

Description:

We aim to develop a rationally designed titanate membrane for EAOP-based water treatment. The titanate membrane will be fabricated through the modification of a membrane substrate with titanate nanowires with excellent conductivity. The ultrathin and porous nanowire network can work as an active layer for electrocatalytic reactions but not block the mass transfer through the membrane. As the contaminated water containing micropollutants and pathogens flows through the electrified reactor equipped with such a membrane, all the titanate nanowire surfaces are potentially reactive for direct electron transfer and radical production for pollutant degradation and microbial inactivation. To achieve this goal, the research team will work on four main 
research tasks: (i) synthesis of ultrathin and conductive titanate nanowires, selection of the optimal porous membrane substrate, and fabrication of the titanate nanowire membrane; (ii) development of lab-scale electrified flow reactor and evaluation of the treatment performance for micropollutant degradation and microbial inactivation, respectively; (iii) integration of the treatment system and investigation of the water matrix impact under prolonged treatment period; and (iv) techno­ economic analysis for real-world application scenario assessment. This project directly contributes to the clean and safe water research goal by developing a small-scale EAOP for drinking water treatment. The method potentially targets a wide range of contaminants in drinking water. In addition, the electrified flow reactor design overcomes the limitations of conventional AOPs. With a focus on point-of-use applications, the project will potentially provide on-demand access to clean and safe drinking water in resource-limited settings for underserved communities.
 

Objective:

Ensuring access to safe and affordable drinking water remains a global challenge. Even with centralized water supply systems, issues such as poor water quality, the presence of emerging contaminants, and the threat of pathogenic microbes persist in both developing and developed countries. Advanced oxidation processes (AOPs) have proven effective for large-scale water and wastewater treatment, but still face challenges in small-scale application scenarios. Electrochemical advanced oxidation processes (EAOPs) offer a promising solution, utilizing electric current for pollutant degradation without the need for complex instruments or continuous chemical supplies. However, long-term operability and cost-effective electrode materials remain critical challenges for EAOP methods. The overarching goal of this study is to develop a small, off-grid, and easily applicable electrified flow-through treatment system equipped with a conductive titanate nanowire-modified membrane for feasible and cost-effective point-of-use water purification and disinfection.

Expected Results:

The proposed research aims to address critical gaps in point-of-use EAOP-based water treatment technology and advance our knowledge by (i) introducing a novel strategy to fabricate the titanate nanowire membrane as the electrode material, (ii) designing a compact flow-through electrified treatment reactor to enhance mass transfer, improve treatment efficiency, and reduce energy consumption, (iii) understanding the roles of complex water matrix in EAOP based water treatment, and (iv) providing insights for implementation of the electrified membrane technique for real-world water treatment applications. The anticipated outcomes include the successful fabrication of titanate nanowire membrane products, the development of a lab-scale electrified flow reactor, and the demonstration of effective micropollutant removal and microbial inactivation performance. The titanate nanowires can potentially be produced in large quantities at low cost, which leads to the feasibility of scaling up the electrified membrane fabrication in the future. Since the electrified membrane technique can achieve the desired treatment performance by simply applying electricity, it will not require any chemicals or complex instruments and not produce any brine or solid wastes. Therefore, the development and implementation of the electrified membrane can realize a sustainable water treatment technique to address the urgent global health concerns associated with water scarcity and poor water quality.

Supplemental Keywords:

Conductive membrane, titanate nanowires, electrochemical advanced oxidation processes (EAOPs), emerging contaminants, pollutant mineralization, microbial inactivation.