香港六合彩

has his research work published in .

It formed part of his postdoctoral research at the聽香港六合彩 Centre for Nature Inspired Engineering (CNIE)聽in the 香港六合彩 Chemical Engineering Department with Prof Marc-Olivier Coppens.

The work was carried out in collaboration with 香港六合彩 Centre for Nature Inspired Engineering (CNIE) researchers Dr. Nidhi Kapil and Dr. Panagiotis Trogadas and was supervised by Marc-Olivier Coppens. 聽

Further information on the publication.

The work introduces the synthesis and performance of new catalytic materials, consisting of hierarchically structured macro-/microporous zeolites with encapsulated metal nanoparticles.聽 聽聽

The introduced catalysts aim to mitigate two major problems present with many catalysts: (1) mass transport limitations, due to slow diffusion in (sub-nanometer) micropores within the zeolite, and (2) catalyst deactivation, caused by sintering of the metal nanoparticles. The hierarchically structured zeolites contain wide 鈥渢ransport pores鈥� (macropores), which enhance the overall diffusion rate of reactants to the catalytic active sites within the microporous zeolite crystals. The noble metal particles are encapsulated within the hierarchical zeolite and accessible via its micropores. The separation of the metal particles by the zeolitic walls prevents the sintering of the metal particles, even at high temperatures. To prove this, the sinter resistance of a conventional gold/TS-1 (titanosilicate-1 zeolite) catalyst was compared to the sinter resistance of the new catalyst with encapsulated gold particles. It was demonstrated that the gold particles of the conventional gold/TS-1 sintered heavily during a treatment at 800掳C, while the encapsulated gold particles in the hierarchical zeolite remained unaltered.

Additionally, catalytic experiments were carried out to investigate the activity of both catalytic sites of the bi-functional, hierarchical zeolites. For this, the direct epoxidation of propylene with hydrogen and oxygen was chosen as test reaction. The reaction relies on gold particles as well as titanium sites in the TS-1 zeolite to activate oxygen and form propylene epoxide. The presented study showed that the hierarchical, bi-functional gold/TS-1 zeolite is active for the direct epoxidation and, therefore, both gold and TS-1 sites must be active and accessible.聽聽聽

Citation with link

Tobias Weissenberger, Nidhi Kapil, Panagiotis Trogadas, and Marc-Olivier Coppens, One-pot synthesis of hierarchical, micro-macroporous zeolites with encapsulated metal particles as sinter-resistant, bifunctional catalysts, ChemCatChem 2022, e202200268

(Available freely via Gold Open Access)