Science Buddies: "Ask an Expert"

is it possible to purify water by splitting it into pure hydrogen and pure oxygen by electrolysis and then somehow reverse the process to make pure H20? I was planning to split non purified H20 and then burn hydrogen in order to make pure water, and i had solar energy in mind to power all of this. When splitting hydrogen and oxygen, it creates alot of energy and i want to somehow turn that energy into the burning of the hydrogen or something like that? and soon after burning the hydrogen it should mix with the oxygen and create steam (H20) which i can collect and make pure water.

At what temperature can the hydrogen be heated up in order to combine with oxygen to make water? I am using solar energy and i do not wish to burn the hydrogen but instead heat it up to the point of that it would combine with oxygen to make pure H20?

Hi,

I think you are onto something with this water purification scheme, but the details are a problem. First off, splitting water into oxygen and hydrogen takes a lot of energy and is usually done by passing electric current through water to which an electrolyte (a salt usually) has been added [http://en.wikipedia.org/wiki/Electrolysis_of_water] If you are planning to use your system on waste water, it may have enough ions already to allow electrolysis. You will have to do some preliminary tests to see how much current is required and at what voltage.

I'm not familiar with how much electric power can be generated from a certain size of solar panel, but i would assume you could produce sufficient voltage/current to split a small amount of water into oxygen and hydrogen. If you don't want to burn the H2 and O2 to produce water then check fuel cells which combine the two gases catalytically, producing water and a bonus--more electricity! [http://americanhistory.si.edu/fuelcells/basics.htm] If a fuel cell could produce enough electricity to split water into O2 and H2 to make all the fuel it needed, then it would indeed be wonderful, but that's thermodynamically impossible. You still need some electric power from a solar panel.

I hope this information helps. Repost with more questions and we will try to keep you on the right track with this great project.

Sybee

Yes i agree and i have been drinking it since young,but chlorine is harmful to our body,if there is a damaged cell or wounds onbody the chlorine help to make things worse,but with zinc water filter,it will heals and repair .and it really tastes sweeter,once i went back to tap water i cannot make myself drink it again.you can really tell the differences.