Synthesis, spectroscopic study and carbofuran adsorption of mixed metal (Co, Cu)@Ca-BTC frameworks aimed at wastewater cleaning

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) 2024, 139(0), , pp.444-457
• Main Authors: Emam, Hossam E., Koto, Teruaki, Sebok-Nagy, Krisztina, El-Shahat, Mahmoud, Abdel-Gawad, Hassan, Pali, Tibor, Abdelhameed, Reda M.
• Format: Article
• Language: English
• Subjects: Adsorption; Ca-BTC; Carbofuran; EPR spectroscopy; Mixed metal-MOF; Wastewater; 화학공학
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2024.05.019

[Display omitted] •Mixed metal-MOFs based on Ca-benzene-1,3,5-tricarboxylic acid (Ca-BTC) were synthesized.•Different metal ions (Mn, Ni, Co, Cu) and Ca were mixed together to produce Ca-M−BTC.•EPR spectrum of Ca-Cu-BTC and Ca-Co-BTC showed a doublet peak at g// = 2.34 and g ∼ 2.1, respectively.•Adsorption of carbofuran followed the second order model and a Langmuir isotherm.•The adsorption capacity onto Ca-Co-BTC and Ca-Cu-BTC were 627.26 and 736.31 mg/g, respectively. The extensive use of insecticides raises a great risk to humans because these compounds are human carcinogens and their agricultural application causes contamination of natural free water. One of the most applied insecticide is carbofuran, and the present study aims at removing it from water using novel mixed metal–metal-organic frameworks (M−MOFs) based on Ca-benzene-1,3,5-tricarboxylic acid (Ca-BTC). Different “guest” metal ions (M = Mn, Ni, Co, Cu; each at 20 %) and Ca (at 80 %) were mixed together with the organic linker BTC to produce Ca-M−BTC. Different geometrical shapes of Ca-M−BTC were observed depending on the type of the added “guest” metal ion. The EPR spectrum of both Ca-Cu-BTC and Ca-Co-BTC shows a doublet peak with line-broadening at g// = 2.34 and a broad peak at g ∼ 2.1, respectively, and the narrow peak provided information about the chelating atoms of the paramagnetic Cu2+ atom. Carbofuran adsorption follows the second order model and a Langmuir isotherm. The adsorption capacity of carbofuran reached 627.26 and 736.31 mg/g onto Ca-Co-BTC and Ca-Cu-BTC, respectively. Efficient carbofuran adsorption on these Ca-M−BTCs, hence removal from water, can be proceeded via both of physical deposition in pores and chemical interaction via H-bonding, coordination and π – π interaction.