The effect of synthesis conditions on the in situ grown MIL-100(Fe)-chitosan beads: Interplay between structural properties and arsenic adsorption

Jessy Joseph; Ari Väisänen; Ajay B Patil; Manu Lahtinen

doi:10.1016/j.jhazmat.2023.132893

The effect of synthesis conditions on the in situ grown MIL-100(Fe)-chitosan beads: Interplay between structural properties and arsenic adsorption

J Hazard Mater. 2024 Feb 5:463:132893. doi: 10.1016/j.jhazmat.2023.132893. Epub 2023 Oct 31.

Authors

Jessy Joseph¹, Ari Väisänen¹, Ajay B Patil², Manu Lahtinen³

Affiliations

¹ Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland.
² Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland; Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Department of Process Metallurgy, Helmholtz Institute Freiberg for Resource Technology (HIF), Freiberg 09599, Germany.
³ Department of Chemistry, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014, Finland. Electronic address: manu.k.lahtinen@jyu.fi.

PMID: 37944234
DOI: 10.1016/j.jhazmat.2023.132893

Abstract

Efficient sequestration of arsenic from drinking water is a global need. Herein we report eco-friendly porous hybrid adsorbent beads for removal of arsenic, through in situ synthesis of MIL-100(Fe) in the chitosan solvogel. To understand the structural vs. performance correlation, series of hybrid adsorbents were synthesized by modulating synthesis conditions like temperature, crystallization time, and concentration. Adsorbents were investigated using PXRD, FT-IR, SEM, and ICP-OES. Intriguing correlation between crystallinity and adsorption performance was observed as low and high crystalline MIL-100(Fe)-chitosan (ChitFe5 and ChitFe7, respectively) exhibited exceptional adsorption towards As⁵⁺ by removing it from water with 99% efficiency, whereas for As³⁺ species removal of about 85% was afforded. Adsorption isotherms indicated that increase in crystallinity (ChitFe5 -> ChitFe7), adsorption capacities of As⁵⁺ and As³⁺ increased from 23.2 to 64.5, and from 28.1 to 35.3 mg/g, respectively. Selectivity tests of the adsorbents towards As⁵⁺ and As³⁺ over competitive anions in the equimolar competitive systems having nitrates, sulfates, and carbonates demonstrated that the performance of the absorbents was fully maintained, relative to the control system. Through this study a highly selective and efficient adsorbent for arsenic species is designed and a clear insight into the structural tuning and its effect on adsorption performance is provided.

Keywords: Aerogels; And crystallinity; Hybrid materials; Metal-organic frameworks.