Preparation of cellulose-chitosan foams using an aqueous lithium bromide solution and their adsorption ability for Congo red
Herein, we present a new process for the preparation of cellulose-chitosan foams using an aqueous lithium bromide (LiBr) solution. After obtaining hydrogels via dissolution-regeneration from an aqueous LiBr solution and methanol, cellulose-chitosan foams were prepared via solvent exchange (water → ethanol → t-butyl alcohol) followed by freeze-drying. The amino group content and elemental analysis confirmed the successful preparation of three foam grades by controlling the blend ratio of cellulose and chitosan. The cellulose-chitosan foams possessed three-dimensional porous networks composed of nano-fibrils. The swelling properties of the foams improved due to the presence of amino groups. The cellulose-chitosan foams exhibited a higher adsorption capacity (1170.2 mg/g) of Congo red compared to the cellulose (623.2 mg/g). The adsorption–desorption process of Congo red demonstrated the strong interactions between chitosan and Congo red. The cellulose-chitosan foams could be applied as an adsorbent for the treatment of industrial wastewater, especially for anionic dyes.
KeywordsCellulose Chitosan LiBr Foam Adsorbent
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology (NRF-2015R1D1A1A01058918 and NRF-2018R1A2B6002983).
- Samiey B, Dargahi MR (2010) Kinetics and thermodynamics of adsorption of congo red on cellulose. Open Chem 8:906–912Google Scholar