guy
National Hazard
Posts: 982
Registered: 14-4-2004
Location: California, USA
Member Is Offline
Mood: Catalytic!
|
|
Why is Pt a good catalyst?
Pt is widely know for catalyzing many reactions, especially with H2. My question is what makes it such a good catalyst? My chem teacher didn't know
why. I searched google and didn't find any explanation. I did however find that H2 can form complexes with metals. Is this the main reason for
catalystic properties of Pt metals? But then, why don't other transition metals catalyze H2 reactions if they all have the ability to adsorb H2?
|
|
Twospoons
International Hazard
Posts: 1324
Registered: 26-7-2004
Location: Middle Earth
Member Is Offline
Mood: A trace of hope...
|
|
Nickel will catalyse hydrogenation reactions. But Pt is better at it. Why? I don't know.
Helicopter: "helico" -> spiral, "pter" -> with wings
|
|
Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
Member Is Offline
Mood: Chemistry: the subtle science.
|
|
IIRC catalysts work by providing a reaction route that requires less energy. I don't know the mechanics for how Pt works, however.
The single most important condition for a successful synthesis is good mixing - Nicodem
|
|
guy
National Hazard
Posts: 982
Registered: 14-4-2004
Location: California, USA
Member Is Offline
Mood: Catalytic!
|
|
I found a site(http://www.science.uwaterloo.ca/~cchieh/cact/applychem/heter...) that describes a little about how it works. All it said was that the Pt adsorbs
H2 and weakens the bonds.
It said other metals may attract H2 too much and not make the reaction work. Some how it said that metals farther left are stronger chemisorbers.
Why? they have larger radius and smaller electron affinity.
|
|
guy
National Hazard
Posts: 982
Registered: 14-4-2004
Location: California, USA
Member Is Offline
Mood: Catalytic!
|
|
This site better explains how hydrogen is chemisorbed to Pt.
http://www.library.uu.nl/digiarchief/dip/diss/2002-1028-1505...
|
|
mick
Hazard to Others
Posts: 338
Registered: 3-10-2003
Member Is Offline
Mood: No Mood
|
|
Catalytic hydrogenation is a 3 phase reaction. Gas, liquid and solid. The solid adsorbs the gas and the liquid makes it work.
mick
Typo
[Edited on 13-2-2006 by mick]
|
|