High-purity hydrogen generated from a single device

Oct 07, 2011 by Lisa Zyga feature
An illustration of the TNA/Pd membrane reactor. Image credit: Hattori, et al. ©2011 American Institute of Physics

(PhysOrg.com) -- There are many ways to generate hydrogen, such as water electrolysis and steam reforming of gas, but the hydrogen produced by these methods tends to be combined with other byproduct and residual gases. For this reason, a second step to purify the hydrogen is usually required after it is produced. Now in a new study, scientists have developed a method for generating hydrogen with a purity of more than 99% within a single membrane, eliminating the need for a separate purification step.

The researchers, Masashi Hattori, Kei Noda, and Kazumi Matsushige, from Kyoto University in Kyoto, Japan, have published their study on the integration of and purification in a recent issue of Applied Physics Letters.

Their method generates hydrogen by shining ultraviolet (UV) light onto a membrane just a few tens of micrometers thick. The membrane is made of two layers: a nanotube array (TNA), which serves as the to generate the hydrogen, and a palladium (Pd) thin film, which serves as the hydrogen purification part.

The membrane forms the basis of a reactor that also includes a UV light and two chambers, one above and one below the membrane. The researchers pumped a fuel, such as or ethanol, into the upper chamber and then turned on the . The light caused a photocatalytic reaction, turning the fuel into carbon dioxide (CO2), formaldehyde (CH2O), and hydrogen (H2) in the upper chamber. In the lower chamber, after passing through the membrane, the researchers measured the purity of the generated H2 to be 99-100% when using either methanol or . Although the scientists did detect some small amounts of CO2 and CH2O in the lower chamber, they concluded that these were not from the but that they were already present as background gases.

“The purification of the produced hydrogen gas was done with the Pd layer,” Noda told PhysOrg.com. “Only hydrogen can pass through the Pd layer and appear in the lower chamber. Other gases still exist inside the upper chamber.”

By integrating the hydrogen generation and purification processes within a single membrane, the researchers hope that the new device will overcome some of the problems faced by previous approaches. For instance, the small membrane reactor, which operates at room temperature, could lead to the miniaturization and low-energy operation of fuel cells, which could have applications for mobile and on-site hydrogen reforming systems. However, the researchers still have a lot of work to do before the device is ready for these applications.

"The performance of the TNA/Pd membrane we reported here is not satisfactory yet," Noda said. “For example, the amount of produced hydrogen with the membrane is quite low at present. The replacement of Pd with Pd alloys with another metal is also necessary to suppress hydrogen embrittlement. In terms of production cost, the thickness of hydrogen permeable metals should be reduced. But, we will make a lot of effort to improve the performance of this new membrane toward practical applications.”

Explore further: New complex oxides could advance memory devices

More information: Masashi Hattori, et al. “High-purity hydrogen generation by ultraviolet illumination with the membrane composed of titanium dioxide nanotube array and Pd layer.” Applied Physics Letters 99, 123107 (2011) DOI:10.1063/1.3643052

4.5 /5 (15 votes)

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kevinrtrs
1.4 / 5 (7) Oct 07, 2011
Now, what to do with that left-over formaldehyde???? They don't say.
rawa1
1.4 / 5 (9) Oct 07, 2011
Formaldehyde can be removed chemically, for example by its reaction with amines or amides. But I don't believe, this process is economically viable anyway with respect to high price of palladium in particular. IMO the only reason of hydrogen economy is to make energy from renewable sources transportable at sufficient energy density. The cold fusion produces energy at sufficient energy density (actually nearly ideal for common use) and it will remove the need of hydrogen transportation anyway. BTW The hidden environmental risks of hydrogen economy is, it can destroy ozone layer with reduction of ozone at high altitude. We don't need to bother with such research at all (one gram of hydrogen/nickel catalyst stores the energy of half ton of oil).

Actually, the cold fusion could produce enough of energy to reverse whole carbon dioxide cycle - so it could be possible to produce artificial hydrocarbons for plastic industry with hydrogenation of carbon dioxide from air.
Pkunk_
2.8 / 5 (9) Oct 07, 2011

Actually, the cold fusion could produce enough of energy to reverse whole carbon dioxide cycle - so it could be possible to produce artificial hydrocarbons for plastic industry with hydrogenation of carbon dioxide from air.


I'm pretty sure you would be welcomed with open arms by other great cold fusion scientists like Ahmedinejad , Hugo Chavez and Fidel Castro. They too believe the Capitalists have been hiding this great secret of Cold Fusion from the world for far too long.
TheGhostofOtto1923
2.1 / 5 (7) Oct 07, 2011
Here is an update on the amazing Energy Catalyzer shipping container. As you can see it is a nice shade of blue and has 2 doors. It produces some kw or mw and was shipped to somewheres in the US. Apparently.
http://energycata...o-public
Jeddy_Mctedder
2.3 / 5 (6) Oct 07, 2011
pure hydrogen finally. put this on a balloon and finally break the godamn record for keeping a balloon aloft .

shockingly people are still stuck on helium.
guess what-all lift gasses escape their envelope slowly. hydrogen is the only renewable lift gas, you can suck h20 out of the air by condensating it, and then get all the free hydrogen you need to replenish your lift gas stocks.
Wolf358
not rated yet Oct 07, 2011
Over time, wouldn't the device get plugged-up with deuterium?
jimbo92107
5 / 5 (7) Oct 07, 2011
pure hydrogen finally. put this on a balloon and finally break the godamn record for keeping a balloon aloft.


Why not replenish your hydrogen supply constantly by placing one of these membranes (sans the palladium) on the top of your lifting body? The small amount of impurities wouldn't matter as far as lifting capacity. You could even burn the excess hydrogen in a simple engine to drive a prop, then drink the exhaust.
eachus
1 / 5 (1) Oct 07, 2011
I just realized that skeptics wrt LENR (aka cold fusion), are making a classic category error. Huh? Ask those same people for their opinion on dark matter, and you will get lots of answers--you can even get long-winded explanations (I'm guilty too on the long part...) of why interactions between the dark matter that is present in the area of the solar system is not detected through interactions with normal matter.

Now suppose someone comes up with a combination of a dark matter candidate and method for detecting it. No need to suppose, some such experiments are getting millions in funding. But do those same physicists spend even 5 seconds considering that LENR could be due to dark matter?

To put up a straw man, if deuterium interacts (through the weak force) with a WIMP, the reaction 2 d --> He4 gamma becomes d (d X) --> He4 X energy. The momentum of the He4 (alpha) particle can be used to calculate the mass of the WIMP.

Now go do the experiment!
SemiNerd
5 / 5 (1) Oct 07, 2011
Over time, wouldn't the device get plugged-up with deuterium?

Given the price of heavy water, if that were so D2 (or DH) would entirely justify the use of these as panels even if the rest of the H2 were just released.

Sadly, I expect that not to be the case.
Callippo
1 / 5 (2) Oct 07, 2011
other great cold fusion scientists like Ahmedinejad , Hugo Chavez
I'm not sure, if the replacement of oil will be welcomed just with these guys. But I can see, many conservatives see the risk of cold fusion in the return of communism. Such people apparently don't care, if the world becomes poor, until they could remain rich in it.
Sean_W
1 / 5 (2) Oct 07, 2011
Less expensive pure hydrogen would no doubt be good news for the chemical industry and make many chemical processes and engineering possibilities more practical.
yoatmon
not rated yet Oct 09, 2011
I'm all else but enthusiastic about using gases or fossil fuels for the production of hydrogen. Several methods with relatively high efficiency have been proposed just using water (even waste waters) on a photosynthesis similar process.
I have a faint suspicion that someone seems to be worried about boycotting or detouring the oil industry.
hudres
not rated yet Oct 09, 2011
Congratulations! PhysOrg has once again reported something as news that is over 50 years old The purification of hydrogen using palladium has been a staple of electron tube manufacture since the second world war. The original hydrogen thyratron electron tube (Google it if you don't know what I am talking about) manufacturing process used palladium to introduce pure hydrogen into the tube during manufacture. In the current world you can buy hydrogen purifiers using palladium from scientific laboratory equipment suppliers.

Have you guys ever heard of fact checking? Try Googling a topic before you print it as news. And, for the record, it is a low efficiency process and it is doubtful that the presence of any membrane will improve it.

BTW: If you don't know what and electron tube is, Google that too.
tadchem
not rated yet Oct 11, 2011
Hydrogen can easily permeate the palladium layer. The molecules dissociate and mass individually through the palladium lattice - something no other element can to as their atoms are too large. Titanium metal has the same property. I would think a TiO2/Ti layer would work as well.
kaasinees
1 / 5 (4) Oct 11, 2011
high-purity hydrogen????
Is non-pure hydrogen contaminated with rogue quarks ? Hmm maybe it wouldn't be hydrogen anymore.

Ahhh the physorg logic... makes so much sense.
yoatmon
not rated yet Oct 12, 2011
The only material that I know of that can contain hydrogen and not allow it to escape is graphene. The lattice between the carbon atoms is so small that hydrogen atoms cannot permeate it.
that_guy
not rated yet Oct 13, 2011
I'm all else but enthusiastic about using gases or fossil fuels for the production of hydrogen. Several methods with relatively high efficiency have been proposed just using water (even waste waters) on a photosynthesis similar process.
I have a faint suspicion that someone seems to be worried about boycotting or detouring the oil industry.

Yeah, I'm pretty sure the breakthrough here is the purity of the Hy, and the price for that purity.

Obviously, this process is not meant to replace traditional fuel, since you're taking something that is already a fuel, and then using energy to turn it into a less practical fuel that has slightly less energy.