Chiral modification of platinum catalysts by cinchonidine adsorption studied by in situ ATR-IR spectroscopy

2001 ◽  
pp. 1172-1173 ◽  
Author(s):  
Davide Ferri ◽  
Thomas Bürgi ◽  
Alfons Baiker
Keyword(s):  
Ir Spectroscopy ◽  
Platinum Catalysts ◽  
Chiral Modification

The Nature of Chemisorbed CO2 in Zeolite A

2019 ◽  
Author(s):  
Przemyslaw Rzepka ◽  
Zoltán Bacsik ◽  
Andrew J. Pell ◽  
Niklas Hedin ◽  
Aleksander Jaworski
Keyword(s):  
Solid State ◽  
Ir Spectroscopy ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Surface Coverage ◽  
Gas Mixtures ◽  
Mas Nmr ◽  
Significant Fraction ◽  
Zeolite A

Formation of CO<sub>3</sub><sup>2-</sup> and HCO<sub>3</sub><sup>-</sup> species without participation of the framework oxygen atoms upon chemisorption of CO<sub>2</sub> in zeolite |Na<sub>12</sub>|-A is revealed. The transfer of O and H atoms is very likely to have proceeded via the involvement of residual H<sub>2</sub>O or acid groups. A combined study by solid-state <sup>13</sup>C MAS NMR, quantum chemical calculations, and <i>in situ</i> IR spectroscopy showed that the chemisorption mainly occurred by the formation of HCO<sub>3</sub><sup>-</sup>. However, at a low surface coverage of physisorbed and acidic CO<sub>2</sub>, a significant fraction of the HCO<sub>3</sub><sup>-</sup> was deprotonated and transformed into CO<sub>3</sub><sup>2-</sup>. We expect that similar chemisorption of CO<sub>2</sub> would occur for low-silica zeolites and other basic silicates of interest for the capture of CO<sub>2</sub> from gas mixtures.

Catalytic activity of rhodium(I) complexes containing (ω-trimethylsilylalkyl)diphenylphosphines

1980 ◽  
Vol 45 (8) ◽  
pp. 2219-2223 ◽  
Author(s):  
Marie Jakoubková ◽  
Martin Čapka
Keyword(s):  
Catalytic Activity ◽  
Nmr Spectroscopy ◽  
Ir Spectroscopy ◽  
Electron Density ◽  
Phosphorus Atom ◽  
Proton Acceptor ◽  
Trimethylsilyl Group ◽  
Kinetics Of

Kinetics of homogenous hydrogenation of 1-heptene catalysed by rhodium(I) complexes prepared in situ from μ,μ'-dichloro-bis(cyclooctenerhodium) and phosphines of the type RP(C6H5)2 (R = -CH3, -(CH2)nSi(CH3)3; n = 1-4) have been studied. The substitution of the ligands by the trimethylsilyl group was found to increase significantly the catalytic activity of the complexes. The results are discussed in relation to the electron density on the phosphorus atom determined by 31P NMR spectroscopy and to its proton acceptor ability determined by IR spectroscopy.

In Situ IR Spectroscopy for Following the Copolymerization of CO2and Epoxides

2014 ◽  
Vol 86 (9) ◽  
pp. 1627-1628
Author(s):  
K. Böhm ◽  
W. Leitner ◽  
T. E. Müller
Keyword(s):  
Ir Spectroscopy ◽  
In Situ Ir ◽  
In Situ Ir Spectroscopy

scholarly journals In Situ IR Spectroscopy of Mesoporous Silica Films for Monitoring Adsorption Processes and Trace Analysis

2018 ◽  
Vol 1 (12) ◽  
pp. 7083-7091 ◽  
Author(s):  
Bettina Baumgartner ◽  
Jakob Hayden ◽  
Andreas Schwaighofer ◽  
Bernhard Lendl
Keyword(s):  
Ir Spectroscopy ◽  
Mesoporous Silica ◽  
Trace Analysis ◽  
Silica Films ◽  
In Situ Ir ◽  
Adsorption Processes ◽  
In Situ Ir Spectroscopy

scholarly journals Monitoring the Interfacial Polymerization of Piperazine and Trimesoyl Chloride with Hydrophilic Interlayer or Macromolecular Additive by in-situ FT-IR Spectroscopy

2019 ◽  
Author(s):  
Xi Yang
Keyword(s):  
Ir Spectroscopy ◽  
Reaction Rate ◽  
Interfacial Polymerization ◽  
Reaction System ◽  
Reaction Rates ◽  
Water Permeation ◽  
Ft Ir ◽  
Trimesoyl Chloride ◽  
Ft Ir Spectroscopy

The interfacial polymerization (IP) of piperazine (PIP) and trimesoyl chloride (TMC) has been extensively utilized to synthesize the nanofiltration (NF) membrane. However, it is still a huge challenge to monitor the IP reaction, because of the fast reaction rate and the formed ultra-thin film. Herein, two effective strategies are applied to reduce the IP reaction rate: (1) the introduction of hydrophilic interlayers between the porous substrate and the formed polyamide layer; (2) the addition of macromolecular additives in the aqueous solution of PIP. As a result, in-situ FT-IR spectroscopy was firstly used to monitor the IP reaction of PIP/TMC reaction system, with hydrophilic interlayers or macromolecular additives. Moreover, we study the formed polyamide layer growth on the substrate, in a real-time manner. The in-situ FT-IR experimental results confirm that the IP reaction rates are effectively suppressed and the formed polyamide thickness reduces from 138&plusmn;24 nm to 46&plusmn;2 nm. Furthermore, the optimized NF membrane with excellent performance are consequently obtained, which include the boosted water permeation flux about 141~238 (L&middot;m2&middot;h/MPa) and superior salt rejection of Na2SO4 &gt; 98.4%.

Ethylene polymerization on a SiH4-modified Phillips catalyst: detection of in situ produced α-olefins by operando FT-IR spectroscopy

2012 ◽  
Vol 14 (7) ◽  
pp. 2239 ◽  
Author(s):  
Caterina Barzan ◽  
Elena Groppo ◽  
Elsje Alessandra Quadrelli ◽  
Vincent Monteil ◽  
Silvia Bordiga
Keyword(s):  
Ir Spectroscopy ◽  
Ethylene Polymerization ◽  
Phillips Catalyst ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Monitoring an ionic liquid synthesis with in-situ IR-spectroscopy – The intricacy of solvent effects

2019 ◽  
Vol 368 ◽  
pp. 649-658 ◽  
Author(s):  
Andreas Ohligschläger ◽  
Christoph Gertig ◽  
Dario Coenen ◽  
Sebastian Brosch ◽  
Dzmitry Firaha ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Ir Spectroscopy ◽  
Solvent Effects ◽  
In Situ Ir ◽  
In Situ Ir Spectroscopy
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