High Pressure Hydrogenation
High Pressure Hydrogenation - Related Videos
06:06
Hydrogenation
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2023
Source: Vy M. Dong and Zhiwei Chen, Department of Chemistry, University of California, Irvine, CA This experiment will demonstrate the hydrogenation of chalcone as an example of an alkene hydrogenation reaction (Figure 1). In this experiment, palladium on carbon (Pd/C) will be used as a heterogeneous catalyst for the process. A balloon will be used to supply the hydrogen atmosphere. Figure 1: Diagram showing the hydrogenation of chalcone to 3-phenylpropiophenone.
07:26
Synthesis and Microdiffraction at Extreme Pressures and Temperatures
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Cited by 5 •
2013
The laser heated diamond anvil cell combined with synchrotron micro-diffraction techniques allows researchers to explore the nature and properties of new phases of matter at extreme pressure and temperature (PT) conditions. Heterogeneous samples can be characterized in situ under high pressure by 2D mapping and combined powder, single-crystal and multigrain diffraction approaches.
10:01
In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure
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Cited by 7 •
2018
A test methodology for quantifying tribological properties of polymers used in hydrogen infrastructure service is demonstrated and characteristic results for a common elastomer are discussed.
08:56
Catalytic Reactor: Hydrogenation of Ethylene
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2023
Source: Kerry M. Dooley and Michael G. Benton, Department of Chemical Engineering, Louisiana State University, Baton Rouge, LA The hydrogenation of ethylene (C2H4) to ethane (C2H6) has often been studied as a model reduction reaction in characterizing new metal catalysts.1-2 While supported nickel is not the most active metal catalyst for this reaction, it is active enough that reaction can take place at < 200°C. The reaction typically involves adsorbed, dissociated hydrogen (H2) reacting...
02:34
Vapor Pressure
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2020
When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor...
FAQs
The catalyst provides a surface on which molecular hydrogen adsorbs and splits into reactive hydrogen atoms. These atoms can then transfer stepwise to the substrate rather than relying only on direct hydrogen addition. This surface-mediated pathway accelerates reaction rates and helps improve conversion under the controlled conditions used for the process.
Pressure increases hydrogen availability at the catalyst surface, which can support more effective reaction with a substrate. This is particularly relevant when the starting compound is less reactive. In practice, elevated pressure can therefore enable reduction of substrates that may respond less readily under lower hydrogen availability, while controlled conditions remain important for the desired conversion.
Selectivity depends in part on which unsaturated functionality receives hydrogen and on how conditions are controlled. Alkenes, alkynes, and carbonyl compounds can follow the same general surface-based hydrogen transfer concept, yet their differing structures affect reaction behavior. Adjusting pressure and other controlled conditions helps regulate which transformations proceed efficiently, supporting product quality rather than simply maximizing hydrogen uptake.
A basic workflow begins by selecting an unsaturated substrate and a suitable metal catalyst, then introducing molecular hydrogen under elevated pressure. The catalyst surface activates hydrogen for stepwise transfer to the substrate. Throughout the process, pressure and other reaction conditions are controlled to promote the intended conversion and help manage selectivity and final product quality.
This process is useful when chemists need to reduce unsaturated compounds or obtain products with controlled composition. Its applications include the synthesis of pharmaceuticals, fine chemicals, polymers, fuels, and modified fats. The ability to improve conversion and regulate selectivity makes it relevant both to laboratory investigations and to chemical manufacturing where consistent product quality matters.
Chemists can evaluate how effectively the substrate has been converted, which transformation occurred, and whether the resulting product meets the desired quality. Pressure and controlled reaction conditions influence both efficiency and selectivity, so these outcomes are considered together rather than separately. This assessment helps determine whether the process is suitable for a particular chemical synthesis or production goal.