Highly Effective Covalently Crosslinked Composite Alginate Cryogels for Cationic Dye Removal

Gels

Vijay Kumar Thakur¹  Mehmet Murat Ozmen²  Serap Sezen² 

[1] Biorefining and Advanced Materials Research Centre, SRUC, Edinburgh EH9 3JG, UK;Department of Bioengineering, Yildiz Technical University, Istanbul 34210, Turkey;

关键词: alginate;    carbodiimide;    cryogel;    composite;    methylene blue;    montmorillonite;   

DOI  :  10.3390/gels7040178

来源: DOAJ

【 摘 要 】

Currently, macroporous hydrogels have been receiving attention in wastewater treatment due to their unique structures. As a natural polymer, alginate is used to remove cationic dyes due to its sustainable features such as abundance, low cost, processability, and being environmentally friendly. Herein, alginate/montmorillonite composite macroporous hydrogels (cryogels) with high porosity, mechanical elasticity, and high adsorption yield for methylene blue (MB) were generated by the one-step cryogelation technique. These cryogels were synthesized by adding montmorillonite into gel precursor, followed by chemical cross-linking employing carbodiimide chemistry in a frozen state. The as-prepared adsorbents were analyzed by FT-IR, SEM, gel fraction, swelling, uniaxial compression, and MB adsorption tests. The results indicated that alginate/montmorillonite cryogels exhibited high gelation yield (up to 80%), colossal water uptake capacity, elasticity, and effective dye adsorption capacity (93.7%). Maximum adsorption capacity against MB was 559.94 mg g⁻¹ by linear regression of Langmuir model onto experimental data. The Pseudo-Second-Order model was fitted better onto kinetic data compared to the Pseudo-First-Order model. Improved porosity and mechanical elasticity yielding enhanced dye removal capacity make them highly potential alternative adsorbents compared to available alginate/montmorillonite materials for MB removal.

【 授权许可】

Unknown