In situ growth of Zr-based metal-organic frameworks on cellulose sponges for Hg2+ and methylene blue removal

Yanxiao Yang; Yunfeng Guo; Zhe Qiu; Weihua Gong; Yonggui Wang; Yanjun Xie; Zefang Xiao

doi:10.1016/j.carbpol.2023.121750

In situ growth of Zr-based metal-organic frameworks on cellulose sponges for Hg²⁺ and methylene blue removal

Carbohydr Polym. 2024 Mar 15:328:121750. doi: 10.1016/j.carbpol.2023.121750. Epub 2023 Dec 30.

Authors

Yanxiao Yang¹, Yunfeng Guo¹, Zhe Qiu¹, Weihua Gong¹, Yonggui Wang², Yanjun Xie¹, Zefang Xiao¹

Affiliations

¹ Key Laboratory of Bio-based Material Science and Technology, Ministry of Education, College of Material Science and Engineering, Northeast Forestry University, Hexing 26 Road, Harbin 150040, PR China.
² Key Laboratory of Bio-based Material Science and Technology, Ministry of Education, College of Material Science and Engineering, Northeast Forestry University, Hexing 26 Road, Harbin 150040, PR China. Electronic address: wangyg@nefu.edu.cn.

PMID: 38220333
DOI: 10.1016/j.carbpol.2023.121750

Abstract

Metal-organic frameworks (MOFs) are characterised by high porosity levels and controllable structures, making them ideal adsorbents for wastewater. However, obtaining substrate materials with mechanical stability, excellent pore accessibility, and good processability for compositing MOF crystal powders to adsorb multiple pollutants in complex aqueous environments is challenging. In this study, porous MOFs@ modified cellulose sponge (MCS) composites were fabricated using MCS as a scaffold to provide anchoring sites for the coordination of Zr⁴⁺ ions and further in situ synthesis of MOFs, namely UiO-66@MCS and UiO-66-NH₂@MCS, which effectively removed heavy metal ions and organic dyes. MOFs@MCS composites exhibit excellent water and dimensional stability, maintaining the pore structure by ambient drying during reuse. Compared with UiO-66@MCS composite, UiO-66-NH₂@MCS composite exhibited a higher adsorption capacity of 224.5 mg·g^-1 for Hg²⁺ and 400.9 mg·g^-1 for methylene blue (MB). The adsorption of Hg²⁺ onto the MOFs@MCS composites followed the Langmuir and pseudo-second-order models, whereas the Freundlich and pseudo-second-order models were more suitable for MB adsorption. Moreover, the MOFs@MCS composites exhibited excellent reusability and were selective for the removal of Hg²⁺. Overall, this approach effectively combines Zr-based MOFs with mechanically and dimensionally stable porous cellulose sponges, rendering the approach suitable for purifying complex wastewater.

Keywords: Cellulose-based sponges; Hg(2+) removal; Metal-organic frameworks; Organic dyes adsorption; Selective adsorption.