One‐pot Green Approach for Rapid and Effective Anionic Dye Remediation: Encapsulation within Alginate Nanocapsules

Abstract

AbstractBACKGROUNDThe encapsulation technique was applied to efficiently eliminate the Congo red (CR) from aqueous solutions. During the ionotropic gelation between Ca2+ ions and alginate (AL), CR was effectively entrapped within the AL nanocapsules in a one‐step process. Suitable conditions for efficient CR removal via encapsulation were revealed by the systematic optimization of parameters including pH, time, rpm, etc.ResultsAccording to the experimental observations, the stirring rate and temperature were found to have an insignificant effect on the encapsulation of CR molecules. When the pH value of the medium was 3, the highest level of encapsulation efficiency was achieved in a period of 15 min. At a preliminary CR concentration of 2000 mg/L and a pH value of 3, the encapsulation efficiency was calculated to be about 98.9%, with an encapsulation capacity of 2800 mg dye/g AL. The zeta potential values of AL and CR/AL nanocapsules were determined to be +7.05 eV and ‐14.9 eV and the results showed that the particles tended to agglomerate. TEM micrographs also showed that the nanopasscules were nanosized and agglomerated. Soil and UV degradation studies showed that the dye‐entrapped nanocapsules were noted to degrade remarkably. These results seriously highlighted the potential of encapsulation for dye removal in terms of the economical and practical applications.ConclusionEncapsulation was confirmed to be an economical and practical technique for effectively eliminating Congo red from aqueous solutions. Under UV light irradiation, the dye molecules entrapped within alginate nanocapsules displayed photodegradation.This article is protected by copyright. All rights reserved.