Aqueous-phase hydrodechlorination of trichloroethylene over Pd-based swellable organically-modified silica (SOMS): Catalyst deactivation due to chloride anions

Date

2018-12-30

Author

Çelik, Gökhan
Gunduz, Seval
Miller, Jeffrey T.
Edmiston, Paul L.
Ozkan, Umit S.

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

207
views

0
downloads

Swellable-organically modified silica (SOMS) has been demonstrated to be an efficient catalyst scaffold for catalytic treatment of water contaminated with trichloroethylene (TCE). In this study, deactivation characteristics of Pd-incorporated SOMS for aqueous-phase hydrodechlorination (HDC) of TCE were investigated. Pd/SOMS catalysts were exposed to highly-concentrated chloride solutions (up to 1 M NaCl or 0.01 M HCl) to examine the deactivation resistant behavior of Pd/SOMS. The commonly used HDC catalyst Pd/Al2O3 was also studied for comparison purposes. Pd/SOMS and Pd/Al2O3 in their pristine and treated states were tested for aqueous-phase HDC of TCE and characterized by several techniques including N2 physisorption, inductively coupled plasma optical emission spectroscopy (ICP-OES), X-ray photoelectron spectroscopy, extended X-ray absorption fine structure spectroscopy (EXAFS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of adsorbed CO. The aqueous-phase treatments had a pronounced adverse effect on the textural properties of Pd/Al2O3, although the effect was independent of the type of the chloride precursor, NaCl or HCl. Treating Pd/Al2O3 with chloride-containing solutions lowered the catalytic activity due to formation of Pd-Cl complexes and active metal leaching. The leached Pd obtained from the treatment solution was shown to be inactive for aqueous-phase HDC of TCE. While Pd/Al2O3 underwent severe deactivation due to the chloride treatments, Pd/SOMS exhibited resistance to chloride deactivation and metal leaching. The chloride treatments did not impact the textural properties of Pd/SOMS. The achieved deactivation resistance was attributed to the novel characteristics of the SOMS support.

Subject Keywords

Process Chemistry and Technology, General Environmental Science, Catalysis

URI

https://hdl.handle.net/11511/40814

Journal

Applied Catalysis B: Environmental

DOI

https://doi.org/10.1016/j.apcatb.2018.08.065

Collections

Department of Chemical Engineering, Article

Suggestions

OpenMETU
Core

Nanoceria supported rhodium(0) nanoparticles as catalyst for hydrogen generation from methanolysis of ammonia borane Ozhava, Derya; Özkar, Saim (Elsevier BV, 2018-12-05) This work reports the preparation and catalytic use of nanoceria supported rhodium(0) nanoparticles, Rh(0)/nanoCeO(2), as catalyst for hydrogen generation from the methanolysis of ammonia borane. Rh(0)/nanoCeO(2) was in situ formed from the reduction of rhodium(II) octanoate on the surface of nanoceria during the catalytic methanolysis of ammonia borane at room temperature. The results of analysis using PXRD, TEM, STEM-EDS, XPS, SEM, SEM-EDX, N-2 adsorption-desorption and ICP-OES reveal that rhodium(0) nano...
Palladium(0) nanoparticles supported on polydopamine coated CoFe2O4 as highly active, magnetically isolable and reusable catalyst for hydrogen generation from the hydrolysis of ammonia borane Manna, Joydev; Akbayrak, Serdar; Özkar, Saim (Elsevier BV, 2017-07-05) Palladium(0) nanoparticles supported on cobalt ferrite (Pd degrees/CoFe2O4) are found to be highly active catalyst, providing an unprecedented catalytic activity with a turnover frequency of 290 min(-1) in hydrogen generation from the hydrolysis of ammonia borane at room temperature. However, the initial catalytic activity of Pd degrees/CoFe2O4 catalyst is not preserved after the reuse of the catalyst in hydrolytic dehydrogenation of ammonia borane. The stability of the catalyst is improved by using the pol...
Rhodium(0) nanoparticles supported on nanosilica: Highly active and long lived catalyst in hydrogen generation from the methanolysis of ammonia borane Ozhava, Derya; Özkar, Saim (Elsevier BV, 2016-02-01) Nanosilica stabilized rhodium(0) nanoparticles (Rh(0)/nanoSiO(2)), in situ formed from the reduction of rhodium(II) octanoate impregnated on the surface of nanosilica, are active catalyst in hydrogen generation from the methanolysis of ammonia borane at room temperature. Monitoring the hydrogen evolution enables us to follow the kinetics of nanoparticles formation. The resulting sigmoidal kinetic curves are analyzed by using the 2-step mechanism of the slow, continuous nucleation and autocatalytic surface g...
Hydroxyapatite supported ruthenium(0) nanoparticles catalyst in hydrolytic dehydrogenation of ammonia borane: Insight to the nanoparticles formation and hydrogen evolution kinetics Akbayrak, Serdar; Erdek, Pelin; Özkar, Saim (Elsevier BV, 2013-10-01) When a solution of ammonia borane is added to the suspension of ruthenium(III) ions supported on hydroxyapatite, both reduction of ruthenium(III) to ruthenium(0) nanoparticles and hydrogen release from the hydrolysis of ammonia borane occur concomitantly at room temperature. Using the hydrogen evolution from the hydrolysis of ammonia borane as reporter reaction provides valuable insights to the formation kinetics of ruthenium(0) nanoparticles. Thus, the rate constants for the slow nucleation and autocatalyt...
Palladium(0) nanoparticles supported on silica-coated cobalt ferrite: A highly active, magnetically isolable and reusable catalyst for hydrolytic dehydrogenation of ammonia borane Akbayrak, Serdar; KAYA, MURAT; Volkan, Mürvet; Özkar, Saim (Elsevier BV, 2014-04-05) Palladium(0) nanoparticles supported on silica-coated cobalt ferrite (Pd(0)/SiO2-CoFe2O4) were in situ generated during the hydrolysis of ammonia borane, isolated from the reaction solution by using a permanent magnet and characterized by ICP-OES, XRD, TEM, TEM-EDX, XPS and the N-2 adsorption-desorption techniques. All the results reveal that well dispersed palladium(0) nanoparticles were successfully supported on silica coated cobalt ferrite and the resulting Pd(0)/SiO2-CoFe2O4 are highly active, magnetica...

Citation Formats

G. Çelik, S. Gunduz, J. T. Miller, P. L. Edmiston, and U. S. Ozkan, “Aqueous-phase hydrodechlorination of trichloroethylene over Pd-based swellable organically-modified silica (SOMS): Catalyst deactivation due to chloride anions,” Applied Catalysis B: Environmental, pp. 654–664, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/40814.