Facile synthesis of CoFe 2 O 4 @MIL-53(Al) nanocomposite for fast dye removal: Adsorption models, optimization and recyclability.

The global occurrence of textile dyes pollution has recently emerged, posing a serious threat to ecological systems. To abate dye contamination, we here developed a novel magnetic porous CoFe ₂ O ₄ @MIL-53(Al) nanocomposite by incorporating magnetic CoFe ₂ O ₄ nanoparticles with MIL-53(Al) metal-organic framework. This nanocomposite possessed a surface area of 197.144 m ²  g ^-1 and a pore volume of 0.413 cm ³  g ^-1 . The effect of contact time (5-120 min), concentration (5-50 mg L ^-1 ), dosage (0.1-1.0 g L ^-1 ), and pH (2-10) on Congo red adsorption was clarified. CoFe ₂ O ₄ @MIL-53(Al) could remove 95.85% of Cong red dye from water with an accelerated kinetic rate of 0.6544 min ^-1 within 10 min. The kinetic and isotherm models showed the predominance of Bangham and Temkin. According to Langmuir, the maximum uptake capacities of CoFe ₂ O ₄ @MIL-53(Al), CoFe ₂ O ₄ , and MIL-53(Al) adsorbents were 43.768, 17.982, and 15.295 mg g ^-1 , respectively. CoFe ₂ O ₄ @MIL-53(Al) was selected to optimize Cong red treatment using Box-Behnken experimental design. The outcomes showed that CoFe ₂ O ₄ @MIL-53(Al) achieved the highest experimental uptake capacity of 35.919 mg g ^-1 at concentration (29.966 mg L ^-1 ), time (14.926 min), and dosage (0.486 g L ^-1 ). CoFe ₂ O ₄ @MIL-53(Al) could treat dye mixture (methylene blue, methyl orange, Congo red, malachite green, and crystal violet) with an outstanding removal efficiency of 81.24% for 30 min, and could be reused up to five cycles. Therefore, novel recyclable and stable CoFe ₂ O ₄ @MIL-53(Al) is recommended to integrate well with real dye treatments systems.
Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest.
(Copyright © 2022 Elsevier Inc. All rights reserved.)