Summary

Innovative Point-of-Use Water Purification System: Portable, Scalable, Efficient, Easy-Use Fresh water in lakes and rivers have supported societies for centuries, unfortunately most water in nature is not drinkable due to the presence of various disease-causing pathogens. Modern cities have extensive infrastructures to supply purified natural water for a functional society. When major hurricanes and floods occur, their access to drinkable water is disrupted, diminishing their resilience. In 2023 so far, 25 catastrophic flood have occurred, each costing the US well over a billion dollars. This is highest number of consecutive events recorded since 1980 by the National Oceanic and Atmospheric Administration (NOAA). The 2021 Texas winter storm resulted in ~14.9 million people experiencing water disruptions. It is critical to develop innovative technologies to provide easy access to drinkable water for individual citizens. Reverse osmosis (RO) and chemical oxidant disinfection are the main approaches for point-of-use (POU) water treatment in the commercial domain. However, the former requires pressurized water and is susceptible to membrane fouling, and the latter employs oxidants, such as ozone, chlorine, and chlorine dioxide, which could generate carcinogenic byproducts affecting people’s health. Recently, solar steaming (SS) has become promising for POU renewable water purification; nevertheless, such devices depend on weather and geographic locations and have limited accountability during extreme weather. The overall project aims to develop a novel electric powered POU water treatment system that can directly fish out live bacteria and remove toxic metal ions, such as Lead and Mercury, in natural water to reach the drinkable level. The device will utilize the enhanced interactions between bacterial cells and a designed high-frequency electric (E) field applied via highly-branched graphite foams to remove bacteria. In a low-frequency E-field, the foam electrodes will generate electroomosis flows in water to readily augment their absorption of toxic metal ions. As a step towards this goal, in this phase-I project, we will exploit an economic, rational approach to fabricate an innovative highly branched graphite foam, and validate and optimize its dual functions towards bacterial disinfection and metal-ion removal in designed AC electric fields. The fabrication of the branched graphite foams will be carried out in a robust manner via leveraging our patent-awarded technique (#11,858,816, 2023) to endow the foams with (a) densely branched structures for bacterial alignment, propulsion, and capture, as well as (b) enhanced ionic absorption capability for the removal of toxic ions. Once successful, this project will deliver a portable, scalable, all-weather, easy-use water purification solution for individual citizens. Fresh water in lakes and rivers has supported societies for centuries; unfortunately, most water in nature is not drinkable due to the presence of various disease-causing pathogens. Modern cities have extensive infrastructures to supply purified natural water for a functional society.

Reverse osmosis (RO) and chemical oxidant disinfection are the main approaches for point-of-use (POU) water treatment in the commercial domain. However, the former requires pressurized water and is susceptible to membrane fouling, and the latter employs oxidants, such as ozone, chlorine, and chlorine dioxide, which could generate carcinogenic byproducts affecting people's health. Recently, solar steaming (SS) has become promising for POU renewable water purification; nevertheless, such devices depend on weather and geographic locations and have limited reliability during extreme weather.

The overall project aims to develop a novel electric-powered POU water treatment system that can directly remove live bacteria and toxic metal ions, such as lead and mercury, from natural water to reach drinkable levels. The device utilizes the enhanced interactions between bacterial cells and a designed high-frequency electric (E) field applied via highly-branched graphite foams to remove bacteria. In a low-frequency E-field, the foam electrodes generate electroosmosis flows in water, readily augmenting their absorption of toxic metal ions.

As a step toward this goal, in this phase-I project, the researchers exploit an economic, rational approach to fabricate an innovative highly-branched graphite foam, and validate and optimize its dual functions toward bacterial disinfection and metal-ion removal in designed AC electric fields. The fabrication of the branched graphite foams is carried out in a robust manner by leveraging the research team's patent-awarded technique (#11,858,816, 2023), endowing the foams with (a) densely branched structures for bacterial alignment, propulsion, and capture, as well as (b) enhanced ionic absorption capability for the removal of toxic ions. Once successful, this project will deliver a portable, scalable, all-weather, easy-to-use water purification solution for individual citizens.