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  • Characterization and Evaluation of Natural Bearing and Iron-Enriched Montmorillonitic Clay as Catalysts for Wet Oxidation of Dye-Containing Wastewaters
Title: Characterization and Evaluation of Natural Bearing and Iron-Enriched Montmorillonitic Clay as Catalysts for Wet Oxidation of Dye-Containing Wastewaters
Natural bearing (raw and calcined at 500 °C) and iron-enriched (impregnation and pillaring) montmorillonitic clay samples were prepared. The obtained samples were characterized (X-ray diffraction, Fourier Transformed Infrared Spectroscopy, Scanning Electron Microscopy, and Energy Dispersive X-ray Spectroscopy) and evaluated as catalysts in catalytic wet oxidation of Brilliant Green and Crystal Violet. Experiments were conducted in the same conditions (0.5 g catalysts, 300 mL air/min or 0.5 mL H2O2, 25 mL of dye solution, 25 °C, initial solution pH = 6.0, for 3 h) in thermostated batch reaction tubes. Process evolution was followed using UV-Vis spectrometry (200–1100 cm−1) and total organic carbon. Dye removal efficiencies (decolorization) between 98 and 99% were determined, while total organic carbon removal efficiencies were calculated to be in the 53–98% range. Iron leakage investigation showed that iron is lost in higher amounts for the catalysts prepared using the impregnation method by comparison with the pillared sample.  more » « less
Award ID(s):
1827176
PAR ID:
10380399
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Catalysts
Volume:
12
Issue:
6
ISSN:
2073-4344
Page Range / eLocation ID:
652
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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