Chemists from the Urals Federal University (UrFU) have discovered the best sorbent (based on amino polymers) to extract silver from solutions. It makes it possible to selectively extract the precious metal, even if its concentration in the solutions is negligible. The new sorbent will not only simplify the extraction of silver in industry, but also help to purify drinking water (a high concentration of silver in water is toxic to the body), in fishing tanks , and will also be useful in production processing. waste. The description of the sorbent has been published in the Russian Journal of Inorganic Chemistry.
“The sorption of metal ions is facilitated by the very nature of the aminopolymer matrix of the sorbents. And the introduction of sulfoethyl groups into it, as our studies show, leads to a significant increase in the selective properties of sorbents – the ability to absorb only some of them from a wide range of different ions” , says Yulia Petrova, head of the research group and associate professor in the Department of Analytical and Environmental Chemistry at UrFU.
According to Petrova, the more sulfoethyl groups in the composition of the sorbent, the better the selective properties.
“Specifically, this work is devoted to the study of the rate of extraction of silver ions from multicomponent solutions in the presence of ions of copper, nickel, cobalt, zinc and several other metals. “, adds Petrova.
During the research, scientists tested four aminopolymer-based sorbents: chitosan, polyallylamine, polyethyleneimine, and polyaminostyrene. These sorbents were synthesized by chemists from the Ural Federal University together with colleagues from the Laboratory of Organic Materials of the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences. As a result, analysis showed that copper ions, more than ions of other metals, interfere with the “selection” of silver. Sulfoethylated polyallylamine has the highest selectivity and sulphoethylated polyaminostyrene has the highest selectivity. In the case of a polyallylamine-based sorbent, even copper is unable to seriously interfere with the sorption process: its initial rate and, therefore, the concentration of sorbed silver ions in the sorbent remain as high as possible. Chitosan is productive in the sorption of silver and copper, and the higher the degree of modification of chitosan with sulfoethyl groups, the higher the selectivity of silver sorption.
“The results of our research make it possible to choose the most effective sorbent to solve certain problems, depending on the degree of modification of the sorbents by sulfoethyl groups, the acidity of the solution, the concentration of metals and the rate of adsorption. . This opens up opportunities to create materials with desired properties, to extract various metals even from solutions in which the content of these metals is negligible,” says Petrova.
– This press release was originally published on the Ural Federal University website