Enhanced removal of Cu(II) ions from aqueous solution by in-situ synthesis of zeolitic imidazolate framework-67@wood aerogel composite adsorbent

ABSTRACT

Zeolitic imidazolate frameworks (ZIFs) were considered to be one of the most promising emerging nanoporous adsorbents capable of efficiently removing a variety of heavy metals ions from wastewater. However, due to the powdered crystalline state, easy aggregation and instability of ZIFs materials, their actual large-scale applications in water matrices are significantly hindered. Compounding ZIFs with self-supporting porous wood aerogel (WA) to obtain advanced composites is excepted to further enhance their adsorption performance with higher practicability. Herein, a novel Zeolitic Imidazolate Framework-67 (ZIF-67)@wood aerogel (denoted as ZIF-67@WA) adsorbent for efficient capture of Cu(II) ions was successfully fabricated via in situ growth of Cobalt-based ZIF-67 particles onto the WA scaffold. Benefiting from the integration of unique three-dimensional porous structures and abundant accessible active sites, the obtained ZIF-67@WA hybrids exhibited fast adsorption kinetics and the maximum adsorption capacity towards Cu(II) calculated from the Langmuir model was 254.84 mg g⁻¹. The adsorption kinetic and isotherm studies were consistent with pseudo-second-order model (R²= 0.991) and Langmuir model (R²= 0.973), indicating the adsorption of Cu(II) was a monolayer chemisorption process. This work proposed a new route for designing and constructing functionalized MOF@biomass hybrid materials for heavy metal wastewater treatment.

KEYWORDS:

• Metal-organic frameworks
• ZIF-67
• wood aerogel
• Cu (II)
• adsorption

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (31860188), the Key Laboratory of State Forestry and Grassland Administration on Highly Efficient Utilization of Forestry Biomass Resources in Southwest China (2022-KF04), and the Scientific Research Fund Project of the Yunnan Provincial Department of Education (2023J0695).