On the dual role of the reactant during aqueous phase hydrodechlorination of trichloroethylene (HDC of TCE) using Pd supported on swellable organically modified silica (SOMS)
APPLIED CATALYSIS B-ENVIRONMENTAL, cilt.291, 2021 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 291
- Basım Tarihi: 2021
- Doi Numarası: 10.1016/j.apcatb.2021.120060
- Dergi Adı: APPLIED CATALYSIS B-ENVIRONMENTAL
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, Environment Index, INSPEC, Metadex, Pollution Abstracts, Civil Engineering Abstracts
- Anahtar Kelimeler: Pd supported on swellable organically modified, silica (SOMS), Hydrodechlorination, Catalyst deactivation, Trichloroethylene, In-situ X-ray absorption near edge spectroscopy, (XANES), Hydrophobicity, CATALYTIC HYDRODECHLORINATION, TURNOVER RATE, WATER, DEACTIVATION, ABSORPTION, PD/AL2O3, ADSORPTION, XAS, NANOPARTICLES, TEMPERATURE
- Orta Doğu Teknik Üniversitesi Adresli: Evet
Özet
Herein, the dual role of trichloroethylene (TCE) in liquid-phase hydrodechlorination with Pd catalysts supported on swellable organically modified silica (SOMS), is investigated. Batch experiments with TCE-soaked Pd/SOMS showed 45% higher conversion after 4 h than dry Pd/SOMS, suggesting that TCE acts as a reactant and as a swelling-agent. Flow experiments performed with and without ethanol (external swelling-agent) exhibited similar steady-state activities, confirming that TCE itself can cause swelling. Moreover, flow experiments, regardless of whether the SOMS-supported Pd catalysts were pre-reduced or not, yielded similar steady-state conversions, suggesting that Pd(2+) is rapidly reduced by H2 dissolved in water during approach to steadystate. In-situ characterization performed under reaction conditions using time-resolved X-ray absorption spectroscopy confirmed the reduction of Pd(2+) species to Pd(0) by dissolved H2. Overall, this study shows economic viability of hydrodechlorination of TCE using Pd/SOMS by eliminating the need for an external swelling-agent as well as a catalyst pre-reduction step.