Expert: Dr. Henry Boyter, Jr. - 9/6/2005

Question
I am interested in the reaction in which water disassociates into it's component hydrogen and oxygen in the presence of a catalyst such as nickel or platinum. I am aproaching this so far from the mechanical side and want to understand the reaction itself. I get lost around calculus somewhere but can usually slug my way thru most formulas so go easy on me.
What volume of water in the presence of what volume/ surface area of catalyst (in particular I am working with nickel but an explanation of why platinum is a better catalyst would be helpful to my understanding as well.)at what tempurature and what pressure causes this reaction? what would be the ideal conditions for this reaction to take place. I have been unable to locate any reference material concerning this so even a point toward the right data would be helpful. I asked a phyicist and he told me to ask a chemist. Thank you. Troy.


Answer
Not my area either.  Try looking up research at http://www.scirus.com/srsapp/  It is going to be catalyst dependent so no general statements can be made.  The amounts are also going to depend on the temperature and pressure. These things are usually figured out by trial and error with the lab results only giving a starting point.  Industrial levels will be different since the process will not be as clean.  How you remove the hydrogen and oxygen will make a difference since O2 usually fouls a catalyst.