Sorption of Salts of Various Metals by Polyelectrolyte Microcapsules

Abstract

Anthropogenic activity negatively affects the environment by polluting it with the salts of various metals. One of the ways to reduce this influence is to use water purification methods for the salts of various metals. Water purification methods based on nanomaterials are promising. In this regard, we proposed to study polyelectrolyte microcapsules (PMC) as a promising sorption agent for the salts of various metals. It was found that the polystyrene sulfonate-polyallylamine (PSS-PAH) polyelectrolyte complex and polyelectrolyte microcapsules of different compositions are not able to adsorb salts CuSO4, Pb(NO)3, FeCl3, and CuCl2. At the same time, it was found that all types of capsules, except for (PSS/PAH)2/PSS, are capable of sorbing about 420 µg of K3[Fe(CN)6] and about 500 µg of K4[Fe(CN)6] from solution. The adsorption of polyelectrolyte microcapsules has an electrostatic nature which is confirmed by increases in the sorption capacity of PMC of K3[Fe(CN)6] and K4[Fe(CN)6] with decreases in the pH of the solution. Also, It was confirmed that the sorption process of PMC of K3[Fe(CN)6] and K4[Fe(CN)6] is concentration dependent and has the limitation of the number of binding sites.

Behaviour of FITC-Labeled Polyallylamine in Polyelectrolyte Microcapsules

“…Non-biodegradable polyelectrolytes, such as polystyrene sulfonate and poly-allylamine, are resistant to biodegradation through natural microbial and enzymatic processes. PMCs based on these materials can withstand more rigorous incubation conditions for extended periods of time, making them suitable for use in industrial and medical diagnostics for determining the pH of the medium [ 22 ], the concentration of low molecular weight compounds [ 34 , 49 , 50 , 51 , 52 ], and surface charge of metals [ 53 ]; in industrial or household water treatment for wastewater purification by sorption [ 54 ], and other types of activities. For example, Reshetilov and colleagues conducted an experiment that demonstrated the effectiveness of the immobilization method utilizing encapsulated glucose oxidase in PMC in a diagnostic system [ 25 ].…”

“…And, when the number of layers is nine or more, a brightly pronounced polyelectrolyte shell appears on the surface of the PMC (Figure 1B). molecular weight compounds [34,[49][50][51][52], and surface charge of metals [53]; in industrial or household water treatment for wastewater purification by sorption [54], and other types of activities. For example, Reshetilov and colleagues conducted an experiment that demonstrated the effectiveness of the immobilization method utilizing encapsulated glucose oxidase in PMC in a diagnostic system [25].…”