Preparation of Al/Fe-PILC clay catalysts from concentrated precursors: enhanced hydrolysis of pillaring metals and intercalation

Galeano, Luis-Alejandro Y Vallejo, Carlos Andrés Y Trujillano, Raquel Y Vicente, Miguel Ángel Y Gil, Antonio (2020) Preparation of Al/Fe-PILC clay catalysts from concentrated precursors: enhanced hydrolysis of pillaring metals and intercalation. Special Publication - Royal Society Of Chemistry, 10 (40450). ISSN 02606291

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Resumen

The modification of bentonite with Al–Fe species from different concentrated precursors at both stages: (i) the preparation of the (Al/Fe)-mixed pillaring solution and (ii) intercalation itself, was studied at lab scale. The final solids were characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Cationic Exchange Capacity (CEC), textural analyses by nitrogen adsorption–desorption at 77 K, and hydrogen-temperature programmed reduction (H2-TPR). Finally, the modified clays were assessed as active materials in the Catalytic Wet Peroxide Oxidation (CWPO) of phenol under very mild conditions through 1.0 h of reaction: T = 25.0 °C ± 0.1 °C, pH = 3.7, ambient pressure (76 kPa), and 0.5 g catalyst per dm3. Metal hydrolysis by the dissolution of elemental aluminium (final Total Metal Concentration TMC = 4.62 mol dm−3) achieved the best results, decreasing the volume of solution per mass unit of clay required to successfully expand the layered starting mineral by a factor of close to 75, in comparison with the widespread conventional preparation using highly diluted Al-based pillaring solutions. Even in the absence of any solvent for the clay dispersion, the intercalating/pillaring method was shown to be favourable, as a novel strategy promoting the process intensification and subsequent preparation of Al/Fe- and other Al-based pillared clays at larger scales. The best catalyst prepared from concentrated precursors exhibited 79.1% phenol conversion, 19.3% TOC mineralization, and pretty low iron leaching (0.037 mg Fe dm−3; ∼0.12% w/w) in such a short catalytic assessment; all these results were quite comparable or even exceeded those exhibited by the catalyst prepared from dilute precursors.

Tipo de Elemento:	Artículo
Asunto:	Q Ciencias > QD Chemistry
Division:	Facultad de Ciencias Exactas y Naturales > Programa de Química > Recursos digitales
Depósito de Usuario:	PhD Luis Alejandro Galeano
Fecha Deposito:	04 Jul 2025 22:29
Ultima Modificación:	04 Jul 2025 22:29
URI:	http://sired.udenar.edu.co/id/eprint/15824

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