Environmental Potential of Carbonized MOF-5/PANI Composites for Pesticide, Dye, and Metal Cations-Can They Actually Retain Them All?

Anka Jevremović; Marjetka Savić; Aleksandra Janošević Ležaić; Jugoslav Krstić; Nemanja Gavrilov; Danica Bajuk-Bogdanović; Maja Milojević-Rakić; Gordana Ćirić-Marjanović

doi:10.3390/polym15224349

Environmental Potential of Carbonized MOF-5/PANI Composites for Pesticide, Dye, and Metal Cations-Can They Actually Retain Them All?

Polymers (Basel). 2023 Nov 7;15(22):4349. doi: 10.3390/polym15224349.

Authors

Anka Jevremović¹, Marjetka Savić², Aleksandra Janošević Ležaić³, Jugoslav Krstić⁴, Nemanja Gavrilov¹, Danica Bajuk-Bogdanović¹, Maja Milojević-Rakić¹, Gordana Ćirić-Marjanović¹

Affiliations

¹ Faculty of Physical Chemistry, University of Belgrade, Studentski trg 12-16, 11158 Belgrade, Serbia.
² Vinča Institute of Nuclear Science, National Institute of the Republic of Serbia, University of Belgrade, P.O. Box 522, 11001 Belgrade, Serbia.
³ Faculty of Pharmacy, University of Belgrade, Vojvode Stepe 450, 11221 Belgrade, Serbia.
⁴ Department of Catalysis and Chemical Engineering, Institute of Chemistry, Technology and Metallurgy, University of Belgrade, Njegoševa 12, 11000 Belgrade, Serbia.

Abstract

The environmental application of the carbonized composites of the Zn-containing metal-organic framework MOF-5 and polyaniline (PANI) in its emeraldine salt and base forms (C-(MOF-5/PANI)) was investigated for the first time. Textural properties and particle size distributions revealed that composites are dominantly mesoporous and nanoscale in nature, while Raman spectroscopy revealed the ZnO phase beneath the carbon matrix. Adsorption of pesticide, dye, and metal cation on C-(MOF-5/PANI) composites in aqueous solutions was evaluated and compared with the behavior of the precursor components, carbonized MOF-5 (cMOF), and carbonized PANIs. A lower MOF-5 content in the precursor, a higher specific surface area, and the pore volume of the composites led to improved adsorption performance for acetamiprid (124 mg/g) and Methylene Blue (135 mg/g). The presence of O/N functional groups in composites is essential for the adsorption of nitrogen-rich pollutants through hydrogen bonding with an estimated monolayer capacity twice as high as that of cMOF. The proton exchange accompanying Cd²⁺ retention was associated with the Zn/Cd ion exchange, and the highest capacity (9.8 mg/g) was observed for the composite synthesized from the precursor with a high MOF-5 content. The multifunctionality of composites was evidenced in mixtures of pollutants where noticeably better performance for Cd²⁺ removal was found for the composite compared to cMOF. Competitive binding between three pollutants favored the adsorption of pesticide and dye, thereby hindering to some extent the ion exchange necessary for the removal of metal cations. The results emphasize the importance of the PANI form and MOF-5/PANI weight ratio in precursors for the development of surface, porosity, and active sites in C-(MOF-5/PANI) composites, thus guiding their environmental efficiency. The study also demonstrated that C-(MOF-5/PANI) composites retained studied pollutants much better than carbonized precursor PANIs and showed comparable or better adsorption ability than cMOF.

Keywords: MOF-5; Methylene Blue; N,O-doped carbon; ZnO; acetamiprid; adsorption; cadmium; composite; polyaniline.

Abstract

Grants and funding