Versatile nanostructured SiO2/cross-linked polyelectrolyte composites for emerging pollutants removal from aqueous media

Linear and branched poly(ethyleneimines) and poly(acrylic acid) have been used in the construction of nanostructured thin multilayer organic shell onto silica microparticles. After glu-taraldehyde selective crosslinking of part of the amino groups, the polyanionic chains were removed on strong basic media. The core/shell microparticles, with amino groups active sites, could interact with anionic charged species dissolved in aqueous media. Batch/column experiments show that the polyanion extracted composites present the best performance toward gallic acid sorption (-30 mg/g composite), as compared to the non-extracted samples (-6 mg/g). The multiple sorption/desorption studies demonstrated the reusability of the composites for water/wastewater treatment applications in at least 10 consecutive cycles without significant loss of sorption capacity.

Automated summary

Linear and branched poly(ethyleneimines) and poly(acrylic acid) were used to construct nanostructured thin organic shells on silica microparticles, with selective removal of polyanionic chains to enhance sorption performance. The extracted composites showed the best sorption capacity for gallic acid, and demonstrated reusability in at least 10 consecutive cycles without significant loss of sorption capacity.