Wastewater is full of dyes and harmful chemicals which if not removed by treatment plants can cause carcinogenic and mutagenic effects.
Activated carbon is usually used in the process which breaks down the waste, reducing the amount of harmful chemicals in the water. The material is used for its efficient absorption of various dyes, heavy metals, and organic contaminants.
However, activated carbon is expensive and is difficult to regenerate. Consequently, researchers are developing cheaper sustainable materials that have the same effect. This year, scientists from the University of Brescia have developed a 3D printable material that reduces toxic compounds in a similar way to activated carbon yet is cheaper and more efficient.
The research team led by Alessandra Zanoletti synthesized a porous and sustainable material from low-cost by-products that is effective in reducing toxic pollutants not only in water but also in the air.
The researchers combined silica fume- an industrial byproduct of silicon metal alloy processing and sodium alginate- a polysaccharide extracted from algae. Alginates are excellent at absorbing ionic dyes and are flexible and elastic yet break easily as the alginate molecular chains are bonded loosely with calcium ions.
For mechanical resistance, the sodium alginate was combined with silica fume, resulting in mechanical stability. When submerged in methylene blue dye the material adsorbed 94% of the chemical.
The material can be 3D-printed and used as a coating which effectively absorbs pollutants in water and the atmosphere. This research illustrates the material’s versatility and opens up new possibilities for pollutant-free building materials.
To read more about the research click here
Researchers include: Alessandra Zanoletti, Ivano Vassura, Elisa Venturini, Matteo Monai, Tiziano Montini, Stefania Federici, Annalisa Zacco, Laura Treccani and Elza Bontempi.