Scientists from NUST MISIS and Pirogov Russian National Research Medical University have created nanoparticles that absorb organic dyes from wastewater due to their correctly structured internal architecture, rather than chemical surface treatment. As reported by the Ministry of Education and Science, traditional sorbents require expensive modification, while the new material does without it and does not lose effectiveness after multiple cycles.
Cobalt ferrite nanoparticles are rods permeated with two types of pores: small, up to 10 nanometers, and large, up to 50 nanometers. The ratio is regulated by the heating rate during firing: the slower the rate, the more small pores. After purification, the particles are instantly removed from the water with a regular magnet. During tests, the material coped with three of the most common dyes — methylene blue, methyl orange, and eriochrome.
As noted by the developers, the pore architecture plays no less important role than surface chemistry. For textile, pharmaceutical, and chemical industries, this means a transition to cheaper and more reliable purification: the sorbent does not need to be modified for each dye; it is enough to adjust the porous structure.