Specific removal of toxic thallium from polluted waters through surface electrostatics and inner pores of Prussian blue metal–organic frameworks: Sorption mechanism and environmental validation
Journal
Journal of Water Process Engineering
Journal Volume
85
Start Page
109555
ISSN
2214-7144
Date Issued
2026-04
Author(s)
Abstract
Thallium (Tl) is a highly toxic element increasingly used in modern technologies, particularly in the electronics, semiconductor, and medical sectors. Industrial activities release Tl into the environment through wastewater discharge, contaminating surface waters and threatening aquatic life even at trace levels. Achieving efficient Tl removal at environmentally relevant concentrations using green and practical material designs remains a major challenge. In this study, a structurally streamlined Prussian Blue metal–organic framework (PB-MOF) with a porous, cube-shaped architecture and low isoelectric point was synthesized. This PB-MOF exhibits high specificity for monovalent Tl(I) across pH 2–9, achieving sorption capacities exceeding 300 mg/g at pH 7–9. The sorption follows pseudo-second-order kinetics and the Temkin isotherm model, driven by dual-domain uptake through electrostatic attraction and size-selective confinement within cage-like pores. Comprehensive physicochemical characterizations confirm that PB-MOFs remain crystalline and structurally stable, and exhibit low acute toxicity during Tl(I) sorption and fish exposure, with K+ replacement by Tl+ observed in synthetic and natural waters. Overall, these results demonstrate that a structurally simple PB-based framework achieves high selectivity, mechanistic clarity, and environmental robustness without composite complexity. PB-MOFs therefore represent eco-friendly, cost-effective sorbents for practical Tl(I) immobilization and in situ water treatment where safe, permanent removal is prioritized.
Subjects
Prussian blue metal-organic framework (PB-MOF)
Removal mechanism
Sorption kinetics and isotherm models
Thallium (Tl)
Water treatment and remediation
Publisher
Elsevier BV
Description
Article number 109555
Type
journal article