The availability of fresh water faces increasing risks due to industrial pollution, the use of dyes in production processes, and the presence of chemicals that reach rivers, lakes, and consumption sources. This situation demands sustainable and accessible solutions, as water purification is essential for health and human development.
Research from Norway
In this context, scientists from the Norwegian University of Science and Technology (NTNU) are working on water purification methods that utilize abundant resources like the sunlight.
Doctoral researcher Jibin Antony, from the Department of Chemical Engineering, emphasizes the importance of developing ecological and affordable technologies: “The sun provides us with a huge amount of free energy. The challenge is to find materials capable of using it to degrade pollutants present in water”.
Photocatalysis as a strategy
The proposal is based on photocatalysis, a process in which certain materials called photocatalysts trigger chemical reactions under the action of light, breaking down harmful compounds into less harmful substances.
The mineral chosen by Antony is bismutite, a bismuth carbonate found in areas of Norway. Although it has photocatalytic properties, its maximum efficiency is only reached under ultraviolet light, which represents a small fraction of the available solar radiation.
Methods to enhance bismutite
To overcome this limitation, Antony tested three approaches:
- Silica modification: improves the adhesion of pollutants and generates structural defects that accelerate the photocatalytic reaction.
- Gold nanoparticles: act as antennas that capture sunlight and enhance the reaction. Although isolated they did not yield significant results, combined with other techniques they increased efficiency.
- Synergy of methods: the combination allowed for improved degradation of pollutants under ordinary sunlight conditions.
Results and projection
The experiments demonstrated that it is possible to significantly increase the capacity of bismutite to purify water using solar energy, without the need for harmful chemicals.
This advancement represents a step towards economic, sustainable water treatment systems based solely on solar energy, with the potential to be applied in rivers, lakes, and human consumption sources.
Antony concluded: “We cannot solve all environmental problems with a single method, but if we manage to purify water through sunlight and smart chemistry, we will have taken an important step”.
The approach opens new possibilities for the sustainable management of water resources, using accessible materials and processes that rely on solar energy. In this way, it facilitates access to safer water without generating additional negative impacts, contributing to addressing one of the most urgent environmental challenges of the 21st century.
