Washcoated Pd/Al2O3 monoliths for the liquid phase hydrodechlorination of dioxins


Autoria(s): Cobo, Martha; Orrego, Andrés; Conesa, Juan A.
Contribuinte(s)

Universidad de Alicante. Departamento de Ingeniería Química

Residuos, Pirólisis y Combustión

Data(s)

13/12/2012

13/12/2012

16/08/2012

Resumo

The catalytic activity and durability of 2 wt.% Pd/Al2O3 in powder and washcoated on cordierite monoliths were examined for the liquid phase hydrodechlorination (LPHDC) of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDD/Fs), also known as dioxins. NaOH was employed as a neutralizing agent, and 2-propanol was used as a hydrogen donor and a solvent. Fresh and spent powder and monolith samples were characterized by elemental analysis, surface area, hydrogen chemisorption, scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX), and transmission electron microscopy/energy dispersive X-ray spectroscopy (TEM/EDX). Three reactor configurations were compared including the slurry and monolith batch reactors as well as the bubble loop column resulting in 100, 70, and 72% sample toxicity reduction, respectively, after 5 h of reaction. However, the slurry and monolith batch reactors lead to catalyst sample loss via a filtration process (slurry) and washcoat erosion (monolith batch), as well as rapid deactivation of the powder catalyst samples. The monolith employed in the bubble loop column remained stable and active after four reaction runs. Three preemptive regeneration methods were evaluated on spent monolith catalyst including 2-propanol washing, oxidation/reduction, and reduction. All three procedures reactivated the spent catalyst samples, but the combustion methods proved to be more efficient at eliminating the more stable poisons.

University of La Sabana, University of Antioquia, and the University of Alicante.

Identificador

COBO, Martha; ORREGO, Andrés; CONESA, Juan A. "Washcoated Pd/Al2O3 monoliths for the liquid phase hydrodechlorination of dioxins". Applied Catalysis A: General. Vol. 445-446 (28 Nov. 2012). ISSN 0926-860X, pp. 83-91

0926-860X (Print)

1873-3875 (Online)

http://hdl.handle.net/10045/25639

10.1016/j.apcata.2012.08.004

A6598026

Idioma(s)

eng

Publicador

Elsevier

Relação

http://dx.doi.org/10.1016/j.apcata.2012.08.004

Direitos

info:eu-repo/semantics/restrictedAccess

Palavras-Chave #Pd/Al2O3 catalyst #Washcoated monoliths #Catalyst deactivation #Dioxins #Fly ash #Ingeniería Química
Tipo

info:eu-repo/semantics/article