Regeneratable Graphene-Based Water Filters for Heavy Metal Removal at Home

Abstract

At-home water filters for drinking water are used by over 100 million Americans. These filters are successful at removing heavy metals from drinking water; however, when heavy metals are present, filters can reach saturation quickly. This currently requires a full filter replacement; treating and regenerating (re-activating) the filter are not currently recommended by filter manufacturers. Here, we present a sustainable graphene-based water filter that can be regenerated by treatment with hot (80 °C) water or vinegar (mild acid). The filter has multiple desirable properties for heavy metal adsorption, including high surface area, conjugation, and oxygen-containing functional groups. This regeneratable filtration technology removes 3- to 65-fold more heavy metals (lead, cadmium, and mercury) from tap water than activated charcoal. Further, the filter can undergo a simple regeneration treatment, allowing for up to 3 cycles of reuse before metal breakthrough occurs. Due to the decreased frequency of filter replacement compared to current technologies, this graphene-based water filter could seamlessly integrate into existing at-home water filtration technologies, providing a more sustainable filter option.