IR spectroscopy of small and weakly interacting molecular probes for acidic and basic zeolites

1998 ◽  
Vol 94 (15) ◽  
pp. 2047-2059 ◽  
Author(s):  
Helmut Knözinger ◽  
Sylvia Huber
Keyword(s):  
Ir Spectroscopy ◽  
Molecular Probes ◽  
Weakly Interacting ◽  
Basic Zeolites

Using in situ IR Spectroscopy to Understand Selective Alkylation of Aromatics over Zeolites

1995 ◽  
Vol 60 (3) ◽  
pp. 421-427 ◽  
Author(s):  
Gabriele Eder-Mirth
Keyword(s):  
Ir Spectroscopy ◽  
Aromatic Ring ◽  
Surface Concentration ◽  
Reaction Products ◽  
Kinetic Measurements ◽  
Methyl Group ◽  
In Situ Ir ◽  
Basic Zeolites ◽  
In Situ Ir Spectroscopy

In situ IR spectroscopy in combination with kinetic measurements was used to clarify the mechanism of the methylation of toluene over zeolitic catalysts. Over basic zeolites (i.e. Rb-X), the main surface species under reaction conditions is toluene strongly bound with the aromatic ring to the cation and with the methyl group to the lattice oxygens of the zeolite. The activated carbon atom of the methyl group reacts with the positively activated C-atom of methanol (formaldehyde) to yield styrene as the main product. Over acidic zeolites (i.e. HZSM-5), methanol is preferentially adsorbed over toluene, the rate of methylation is directly proportional to the surface concentration of the activated methanol species (methoxonium ions at low and methoxy groups at high reaction temperatures). The aromatic ring of toluene is attacked by the reactive alcohol methyl group, giving the xylene isomers as reaction products.

Assessing the surface sites of the large pore 3-dimensional microporous material H-ITQ-7 using FT-IR spectroscopy and molecular probes

2011 ◽  
Vol 141 (1-3) ◽  
pp. 146-156 ◽  
Author(s):  
Ragnhild Skorpa ◽  
Silvia Bordiga ◽  
Francesca Bleken ◽  
Unni Olsbye ◽  
Bjørnar Arstad ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Molecular Probes ◽  
Microporous Material ◽  
3 Dimensional ◽  
Surface Sites ◽  
Large Pore ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

IR SPECTROSCOPY WITH SURFACE ELECTROMAGNETIC WAVES

1984 ◽  
Vol 45 (C5) ◽  
pp. C5-167-C5-178
Author(s):  
A. J. Sievers ◽  
Z. Schlesinger ◽  
Y. J. Chabal
Keyword(s):  
Ir Spectroscopy ◽  
Electromagnetic Waves ◽  
Surface Electromagnetic Waves

Search for weakly interacting massive dark matter particles: state of the art and prospects

2020 ◽  
Author(s):  
Andrei B. Aleksandrov ◽  
Aigerim B. Dashkina ◽  
Nina S. Konovalova ◽  
Natal'ya M. Okat'eva ◽  
Natal'ya G. Polukhina ◽  
...  
Keyword(s):  
Dark Matter ◽  
State Of The Art ◽  
Weakly Interacting
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