A 'top modification' strategy for enhancing the ability of a chitosan aerogel to efficiently capture heavy metal ions

Shize Li; Yaping Li; Zi Fu; Lingbin Lu; Jingru Cheng; Yongsheng Fei

doi:10.1016/j.jcis.2021.03.029

A 'top modification' strategy for enhancing the ability of a chitosan aerogel to efficiently capture heavy metal ions

J Colloid Interface Sci. 2021 Jul 15:594:141-149. doi: 10.1016/j.jcis.2021.03.029. Epub 2021 Mar 15.

Authors

Shize Li¹, Yaping Li¹, Zi Fu¹, Lingbin Lu², Jingru Cheng¹, Yongsheng Fei¹

Affiliations

¹ Special Glass Key Lab of Hainan Province, School of Materials Science and Engineering, Hainan University, Haikou 570228, China.
² Special Glass Key Lab of Hainan Province, School of Materials Science and Engineering, Hainan University, Haikou 570228, China. Electronic address: lulingbin@126.com.

PMID: 33756362
DOI: 10.1016/j.jcis.2021.03.029

Abstract

Chitosan is a promising substitute for heavy metal ion adsorbents. However, traditional pure chitosan adsorbents have certain disadvantages that limit their application. In this paper, a 'top modification' strategy was used to enhance the capturing ability of chitosan adsorbents. A chitosan aerogel was prepared via physical crosslinking and then enhanced by immersion in ethylenediamine tetraacetic anhydride solution. Finally, an enhanced chitosan aerogel was obtained, and analyses were used to describe its structure, adsorption properties and mechanism. Results showed that both the porous structure and the combined complexations dramatically improved the capturing ability of the chitosan aerogel for heavy metal ions. The theoretical adsorption capacities of the enhanced aerogel for Cu²⁺, Pb²⁺ and Cd²⁺ reached 108.14, 143.73 and 84.62 mg/g, respectively. Due to their environmental friendliness, good adsorption performance, easy separation and reusability, enhanced aerogels have become viable solutions to removing heavy metal pollutants from aquatic systems.

Keywords: Adsorbent; Chitosan aerogel; Ethylenediamine tetraacetic anhydride; Heavy metal ion; Physical crosslinking.