While we've seen quite a few filtration systems that make contaminated water drinkable, many are quite complex or use expensive materials. In contrast, a new experimental setup simply requires users to inject dirty water into a layer of cellulose. The prototype device, developed by scientists at the University of Texas at Austin, consists of a roughly hockey-hockey-shaped shell containing a hydrogel film dotted with micropores.
Hydrogel is composed of cellulose nanofibers "interwoven into a network". Cellulose is the most common organic compound on earth - it can be obtained easily and cheaply from a variety of readily available natural resources, including plants.
To use the device, users first use a regular syringe to draw water from a stream, lake, or other location. They then inserted one end of the syringe into a port on the top of the filter and injected water into it.
When water passes through the tiny gaps between nanofibers, almost 100% of suspended solid particles larger than 10 nanometers are trapped, while bacteria and viruses often exceed 10 nanometers in size. This way, the water that comes out of the bottom of the filter becomes clean and drinkable. What's more, each filter can be used 30 times and is biodegradable when discarded.
In tests conducted so far, large 1.5-liter (1.6-quart) syringes have been used to collect murky water, river water, and water contaminated with microplastics, all of which were successfully purified using the filter. Scientists are currently working to scale up the technology to treat larger volumes of water at once.
Chief Scientist Professor Yu Guihua said: "The problem of particulate matter contaminating water is imminent, especially in remote and underdeveloped areas, where people often rely on contaminated water sources for drinking, which requires immediate attention and attention. Our system can efficiently remove various types of particles, providing an attractive and practical solution for improving fresh water supply."
A paper on the research was recently published in the journal Nature Sustainability.