A new technology for water purification inspired by natural loofah.

 

Hydrogel has become a promising material in many applications, as it can be adapted for use in energy and environmental areas, including sustainable water collection and purification techniques. However, the current impediment to the diffusion of this technology is the low rate of production.

In order to overcome this challenge, a team from Princeton University of the United States developed hydrogella that is responsive to temperature change, inspired by the installation of a natural shower "Love".

This hydrogel is capable of absorbing contaminated water from any source at normal temperatures, purifying it by solar energy, and with temperature raising it can release clean water in only 10 minutes and even in cloudy weather conditions, at a rate sufficient to meet daily needs.

The results of the study were published on February 8 in ACS Central Science, published by the American Chemical Society.

High porosity inspired by Love Shower

Researchers have suggested that sunlight-induced evaporation may be an economically inexpensive way to purify water, but this technique does not work with acceptable efficiency when the weather is cloudy.

In particular, hydrogel responders to temperature change such as poly-in-isopropyl acrylamide (PNIPAm) can be one solution to overcoming this problem and leveraging this technology to achieve the sixth United Nations Sustainable Development Goal, "Ensuring clean water and hygiene for all".

This polymer is one of the easiest to respond to temperature change in operation, absorbing water at low and moderate temperatures and releasing it easily once lifted. However, the traditional "poly-in-isopropylacrylamide", because it is not available on pores, is unable to produce a quantity of clean water sufficient for an individual's daily needs.

Because it is scientifically proven to be the expulsive relationship between porosity and fluid flow, the aim was to prepare a substance characterized by high porosity and resistance to obstruction. The team designed hydrogela based on the heat-responsive polymer "poly-in-isopropylacrylamide".

Unprecedented production and purification rate

It was necessary to test the efficiency of the hydrogel prepared polymer loaf to ensure that it conformed to the required specifications. It was first tested under the influence of an industrial solar source, and secondly to determine its efficiency in purifying water from some pollutants.

The results illustrated the success of the new substance in absorbing and freeing 70% of the water used in the experiment, which means producing pure water 4 times higher than the hydrogel productivity rate observed in previous studies and in just 10 minutes.

Lough was also tested under low light conditions and partially overcast skies, and purification took 15 to 20 minutes until the material released a similar amount of water.

According to the press release published on Viz Dot Org (Phys.org), researchers stated that at this rate, the new substance has the capacity to meet an individual's daily needs.

The loaf was then tested on water samples contaminated with organic pigments, heavy metals, oil and microplastics. All tests have demonstrated the factory's efficiency in purifying water with good efficiency.

For example, the efficiency of the loff was tested on water samples containing about 40 parts per million of chromium, and the results confirmed the porous hydrogel efficiency in purifying this water, as the concentration of chromium in purified water was less than 0.07 parts per million, less than the permissible limit of chromium for drinking water.

The research team also says that the lofty composition of the unique hydrogel devised can be useful in additional applications such as smart sensors, as well as chemical separation.