Preparation of molecularly imprinted chitosan/carboxymethyl cellulose hollow vesicles for selective dye adsorption

To improve the selective adsorption of the target pollutant, this study successfully synthesized chitosan/carboxymethyl cellulose molecularly imprinted hollow vesicles (CS/CMC-MIV) for selective adsorption of acid blue-113 (AB-113). The vesicles were obtained by mixing the carboxymethyl cellulose solution with the chitosan/AB-113 mixture in sequential fast and slow stirring. Benefiting from the molecular imprinting technique, the maximum adsorption capacity of AB-113 by CS/CMC-MIV was 972.7 mg/g, which was 84.8% higher than that of the vesicles without imprinting (526.4 mg/g). The adsorption process could be well in accordance with Langmuir isotherm and pseudo-second-order models. The vesicles exhibited superior stability and reusability, maintaining 92% of the initial adsorption capacity after four adsorption repeats. What's more, CS/CMC-MIV showed excellent selective adsorption ability on mixed dye solutions, which was attributed to the specific recognition sites created during the molecular imprint process. This study provides a facile method to bind dye templates to vesicles and excels at selective dye removal.