Kinetic analysis of the catalytic hydrogenation of alkyl levulinates to γ-valerolactone

2017 ◽  
Vol 158 ◽  
pp. 545-551 ◽  
Author(s):  
Leila Negahdar ◽  
Mohammad G. Al-Shaal ◽  
Fabian J. Holzhäuser ◽  
Regina Palkovits
2017 ◽  
Vol 19 (23) ◽  
pp. 5527-5547 ◽  
Author(s):  
Long Yan ◽  
Qian Yao ◽  
Yao Fu

This article presents a comprehensive review of the catalytic hydrogenation of levulinic acid and alkyl levulinates into their derived biofuels and high-value chemicals, and includes the synthesis of levulinic acid and alkyl levulinates from biomass derivates.


2019 ◽  
Vol 21 (19) ◽  
pp. 5195-5200 ◽  
Author(s):  
Rosa Padilla ◽  
Mike S. B. Jørgensen ◽  
Márcio W. Paixão ◽  
Martin Nielsen

Catalytic hydrogenation of alkyl levulinates to γ-valerolactone is achieved under mild reaction conditions employing pincer PNP-M complexes. High efficacy is demonstrated with TON's exceeding 9000. Furthermore, the feasibility of recycling is shown.


1965 ◽  
Vol 13 (01) ◽  
pp. 155-175 ◽  
Author(s):  
H. C Hemker ◽  
P.W Hemker ◽  
E. A Loeliger

SummaryApplication of the methods of enzyme-kinetic analysis to the results of clotting tests is feasible and can yield useful results. However, the standard methods of enzyme kinetics are not applicable without modifications imposed by the peculiarities of the blood-clotting enzyme system. The influence of the following complicating circumstances is calculated :1. Substrate is not present in excess.2. Only relative measures exist for concentrations of substrate or enzymes.3. Enzymes and substrates are often added together.4. Reagents are not pure.5. Clotting-time is our only measure for clotting-velocity.Formulas are deduced, which makes it possible to recognize the effect of these complications.


1995 ◽  
Vol 32 (4) ◽  
pp. 225-231 ◽  
Author(s):  
Toru HARIGAI ◽  
Shinya KIMURA ◽  
Shuichi KAKURAI
Keyword(s):  

2020 ◽  
Author(s):  
hao yin ◽  
Liqing Zheng ◽  
Wei Fang ◽  
Yin-Hung Lai ◽  
Nikolaus Porenta ◽  
...  

<p>Understanding the mechanism of catalytic hydrogenation at the local environment requires chemical and topographic information involving catalytic sites, active hydrogen species and their spatial distribution. Here, tip-enhanced Raman spectroscopy (TERS) was employed to study the catalytic hydrogenation of chloro-nitrobenzenethiol on a well-defined Pd(sub-monolayer)/Au(111) bimetallic catalyst (<i>p</i><sub>H2</sub>=1.5 bar, 298 K), where the surface topography and chemical fingerprint information were simultaneously mapped with nanoscale resolution (≈10 nm). TERS imaging of the surface after catalytic hydrogenation confirms that the reaction occurs beyond the location of Pd sites. The results demonstrate that hydrogen spillover accelerates hydrogenation at the Au sites within 20 nm from the bimetallic Pd/Au boundary. Density functional theory was used to elucidate the thermodynamics of interfacial hydrogen transfer. We demonstrate that TERS as a powerful analytical tool provides a unique approach to spatially investigate the local structure-reactivity relationship in catalysis.</p>


2020 ◽  
Author(s):  
Hao Yin ◽  
Liqing Zheng ◽  
Wei Fang ◽  
Yin-Hung Lai ◽  
Nikolaus Porenta ◽  
...  

<p>Understanding the mechanism of catalytic hydrogenation at the local environment requires chemical and topographic information involving catalytic sites, active hydrogen species and their spatial distribution. Here, tip-enhanced Raman spectroscopy (TERS) was employed to study the catalytic hydrogenation of chloro-nitrobenzenethiol on a well-defined Pd(sub-monolayer)/Au(111) bimetallic catalyst (<i>p</i><sub>H2</sub>=1.5 bar, 298 K), where the surface topography and chemical fingerprint information were simultaneously mapped with nanoscale resolution (≈10 nm). TERS imaging of the surface after catalytic hydrogenation confirms that the reaction occurs beyond the location of Pd sites. The results demonstrate that hydrogen spillover accelerates hydrogenation at the Au sites within 20 nm from the bimetallic Pd/Au boundary. Density functional theory was used to elucidate the thermodynamics of interfacial hydrogen transfer. We demonstrate that TERS as a powerful analytical tool provides a unique approach to spatially investigate the local structure-reactivity relationship in catalysis.</p>


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