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Self-Sustaining Solar Reactor Creates Clean Hydrogen
An anonymous reader writes "A mechanical engineer working out of the University of Delaware has come up with a way to produce hydrogen without any undesirable emissions such as carbon dioxide. The solar reactor is capable of using sunlight to increase the heat inside its cylindrical structure above 3,000 degrees Fahrenheit. Zinc oxide powder is then gravity fed through 15 hoppers into the ceramic interior where it converts to a zinc vapor. At that point the vapor is reacted with water separately, which in turn produces hydrogen. If the prototype gets through 6 weeks of testing at the Swiss Federal Institute of Technology located in Zurich, we could see it scaled up to industrial size, producing emission-free hydrogen."
One reason storing it is such a big deal is because generating it can be expensive. Make hydrogen easier to produce and it lowers the demands on storage.
I work for the Department of Redundancy Department.
TFAs: Read one today!
How can I believe you when you tell me what I don't want to hear?
You start with zink oxide. Apparently (not a chemist here) you de-ogygenate it via heat making zink vapor (releasing O2, which is vented) and that zink vapor grabs oxygen from the water, leaving you with your H2 product, and a clean supply of Zink Oxide again.
The byproduct is Oxygen.
Sig Battery depleted. Reverting to safe mode.
The recovery could be pretty close to 100%; the reactor's only products are oxygen and hydrogen, both of which are gases, so capturing zinc should be simple enough.
Zinc is usually found in conjunction with other metals like copper, so we get most of it "for free". Zinc oxide is actually a lot easier to produce than pure zinc, so refinement costs should be relatively low. The most common ore of Zinc, Sphalerite, is ZnS, and converting it to ZnO just involves adding oxygen and heat:
ZnS + (3)O2 = ZnO + SO2
The sulphur dioxide can be converted to sulphuric acid (H2SO4).
No carbon involved.
Besides, we already use >10 million tons of the stuff per year, and have at least a couple centuries more deposits to mine (to say nothing of recycling), so using a bit for this solar plant wouldn't even be noticed.
How can I believe you when you tell me what I don't want to hear?
Hydrogen exceeding ~4.5% in air is explosive, so a slow leak in a ventilated area just escapes into the atmosphere. A faster leak, or a poorly ventilated area presents a tremendous explosion potential. Remember the reactor buildings in Fukushima? Those were from hydrogen building up inside the building.
make imaginary.friends COUNT=100 VISIBLE=false