Work

Aqueous-phase fabrication of cellulose-mineral composites with enhanced Cd(II) adsorption and mechanistic insights

Year: 2025

Type: article

Abstract: In this study, a green and sustainable synthesis strategy was developed to fabricate cellulose-based composite adsorbents by replacing the organic dispersion system previously used with an aqueous medium. Two inorganic fillers, sepiolite and TiO₂, were respectively incorporated to prepare cellulose-sepiolite (CgS(H₂O)) and cellulose-TiO₂ (CgT(H₂O)) composites, aiming to investigate the influence of mineral type and dispersion phase on Cd(II) adsorption performance and mechanism. Compared to the earlier reported CAT material synthesized in organic media, both aqueous-phase composites showed enhanced porosity, surface functionality, and carboxyl group distribution. CgS(H₂O) exhibited a fluffy, porous network structure with high micro/mesopore connectivity, achieving a maximum Cd(II) capacity of 239.45 mg/g. CgT(H₂O), with higher surface area and Ti–O active sites, demonstrated the highest capacity of 368.82 mg/g, significantly surpassing CAT (105 mg/g). Kinetic and isotherm analysis revealed that CgS(H₂O) followed multilayer chemisorption, while CgT(H₂O) conformed to monolayer Langmuir-type adsorption. Density functional theory (DFT) simulations further indicated stronger binding affinities and more active carboxyl-dominant sites in CgT(H₂O), while CgS(H₂O) benefited from networked carboxyl groups and Si–O-based interaction domains. These findings collectively highlight that the aqueous dispersion strategy, combined with targeted mineral selection, enhances not only environmental friendliness but also material structure and adsorption efficiency, offering a versatile platform for efficient heavy metal removal from water. • Aqueous grafting used as a green route instead of organic dispersion synthesis. • Sepiolite and TiO₂ were integrated into cellulose to prepare hybrid composites. • CgT(H₂O) and CgS(H₂O) reached Cd(II) adsorption of 368.82 and 239.45 mg/g. • Cd(II) removal involved complexation, chemisorption, and π–π interactions. • DFT revealed strong Cd(II) binding at –COOH sites and key electronic interactions.

Source: Industrial Crops and Products

DOI: 10.1016/j.indcrop.2025.122133

Authors: Peipei Meng, Qianya Zhou, Na Zhang, Lijuan Zhang, Liuchun Zheng

Institutions: Jinan University, South China Normal University, South China University of Technology

Language: English

Topic: Adsorption and biosorption for pollutant removal

Subfield: Water Science and Technology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Clean water and sanitation, Responsible consumption and production

Open Access status: gold

Estimated APC paid: $3,720