1. Nano-zerovalent manganese/biochar composite for the adsorptive and oxidative removal of Congo-red dye from aqueous solutions.
- Author
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Iqbal J, Shah NS, Sayed M, Niazi NK, Imran M, Khan JA, Khan ZUH, Hussien AGS, Polychronopoulou K, and Howari F
- Subjects
- Adsorption, Charcoal, Congo, Hydrogen Peroxide, Hydrogen-Ion Concentration, Kinetics, Manganese, Oxidative Stress, Solutions, Water, Congo Red, Water Pollutants, Chemical analysis
- Abstract
Congo-red (CR), a precursor of textile products and a contaminant of great concern, has contaminated aquatic environments. Here, we explored the synthesis of mesoporous nano-zerovalent manganese (nZVMn) and Phoenix dactylifera leaves biochar (PBC) composite for the removal of CR from water. The nZVMn/PBC adsorbed 117.647 mg/g of CR versus 25.316 mg/g by PBC at [CR]
0 = 20 mg/L and [PBC]0 = [nZVMn/PBC]0 = 500 mg/L. Variation of [nZVMn/PBC]0 , [CR]0 and pH influenced the adsorption of CR. Freundlich adsorption isotherm and pseudo-first-order kinetic models best fitted CR adsorption. The H2 O2 coupling with nZVMn/PBC promoted removal of CR possibly due to the formation of hydroxyl radical (● OH) and caused 95 % removal of CR versus 77 % by nZVMn/PBC alone. The● OH scavengers inhibited the removal of CR. The nZVMn/PBC showed a good reusability and efficient removal of CR up to the seventh cycle of treatment. Results reveal that nZVMn improved performance, thermal stability and reusability of biochar. Degradation products from● OH-mediated degradation of CR were studied by ultraperformance liquid chromatography with mass spectrometric detector to establish degradation pathways. The ion-chromatographic analysis showed the formation of non-toxic inorganic acetate product, which suggests high potential of the newly fabricated adsorbent in the removal of CR., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2021
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