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Micromotors Race About By Turning Water Into Hydrogen Gas
MTorrice writes "Microscopic particles of aluminum and gallium rocket around using water as their fuel. The particles, which are 20 micrometers in diameter, are asymmetric: A chemical reaction on the back side of the particle forms hydrogen gas bubbles that propel the motor forward. Over the past several years, bioengineers have built micro- and nanosized rockets that zip through liquids, fueled by chemical reactions between the materials that make up the rockets and their environments. The engineers hope someday these tiny motors could help deliver cargo, such as drugs, in people. Unfortunately, many of these motors require toxic hydrogen peroxide as fuel source, limiting their use in the body. To overcome that constraint, the new micromotors harness a well-known reaction between aluminum and water to produce hydrogen gas."
I don't know bow it's administered, but I'd rather die...
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If the rocket blurbs out H2 and the backends, and as I understand, water is made of 2 Hydrogen and 1 Oxygen (H2O), where has the Oxygen gone to?
Muchas Gracias, Señor Edward Snowden !
Read TFA - or heck, even just the /. blurb, and you'll see aluminum is consumed in the reaction to produce hydrogen. It's not free energy.
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
...just not widely reported
"Waste not one watt!" - CZ
is this something that could be used to cheaply make hydrogen for fuel? If you put 6.02 * 10^23 of them in water how much hydrogen would it produce?
If you've cut yourself at all in the course of these tests, you may have noticed that your blood is pure hydrogen- that's normal. We've been shooting you with an invisible micromotor that's supposed to turn blood into hydrogen, so all that means is it's working.
"You should always go to other people's funerals; otherwise, they won't come to yours." -- Yogi Berra
You're better off buying an electolyzer for $150-$1000. Electrolyzer required distilled water. Distillers are pretty cheap too, lets say you can get one for 150$.
Now the cool thing coming out is Toyota's Hydrogen Car for 50k or so in 2015. In order to store hydrogen in a tank, you must first compress it. Hydrogen is a material that erodes a lot of materials it comes in contact with, so dealing with it is somewhat more challenging than other fuels. Compressors exist for hydrogen, but I couldn't find a price for under $12k. Before I become a hobbyist in this, I need to make sure I can afford it, and $12k for the compressor is what makes working on a personal hydrogen refueling station unfeasible for me.
I think if hydrogen car economy takes off, everyone will have their own refueling station because the only two inputs required are: Electricity and Water. Then you lose some power converting the electricity into hydrogen but being able to store it in fuel tanks as opposed to expensive batteries that wear out makes it nice. We're looking forward to time where people invest in their own solar panels on their property so they pay less in utilities too.
I think in the short run of a hydrogen economy, you'll have hydrogen refueling stations, but in the long run, people will be making personal stations too. Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline. Of course if the price of the car is greater than the price of a gas powered car and its lifetime of gasoline, there is only going to be a niche market. But if Toyota can get these things for under $25k and they don't have any serious downsides like the electric car's problem of battery arrays dying.... It could be the future.
Because of this, I want to become a hobbyist, and maybe own my own refueling station some day, but I don't want to get too involved if I can't afford a hydrogen compressor. Anyone know of a place to get a hydrogen compressor for under $12k?
God spoke to me
argh, again this kind of misleading headline that makes the people who only read the headline think a perpetual machine is finally invented.
The energy comes from aluminium, aluminium "burning" into aluminium-oxide.
Putting the "converting water into hydrogen" into headline is misleading reporting.
Why do you think it kills the germs in a cut?
Notice how it foams up as soon as it hits blood? Blood is full of peroxidase. Breaking down hydrogen peroxide into water and oxygen is routine housekeeping, since your body actually produces hydrogen peroxide as a weapon for the immune system to use.
So: toxic, but gets detoxified almost instantly, and anyway wouldn't it be in the equivalent of a fuel tank?
Besides harmless emissions from hydrogen, the cost of fuel will be extremely low compared to gasoline.
Only if the cost of the electricity used to hydrolyze the water is also extrememly low. For the foreseeable future, the only viably-large source of electricity that is close to carbon neutral will likely be nuclear power - sun and wind likely won't be sufficient for a long time. Also, power from sun, wind, and fission are currently priced artificially higher than power from oil, because with oil we're 'borrowing' from future generations to support our extravagant lifestyle but aren't even calculating the principal, never mind the interest...
I'm all in favour of building 'hydrogen economy' vehicles and infrastructure right now, even though it's not yet clear exactly how we'll come up with enough clean energy to justify it, unless we go all-out nuclear, the prospect of which scares the sh*t out of me. But let's be VERY clear that in the short term we may in fact be increasing carbon emissions by doing so. There are WAY too many people out there who see zero emissions at the tailpipe and think the problem is solved, when in fact total emissions per mile driven may well be higher than those produced by a gasoline engine. Joe Public needs to be educated about such things, and the makers of various 'environmentally friendly' technologies aren't about to do that if it risks harming their sales. We in the tech and scientific communities have an obligation to start getting the word out that There Ain't No Such Thing As A Free Lunch.
'The Economy' is a giant Ponzi scheme whose most pitiable suckers are the youngest among us and the yet-unborn.
Using Electrolysis is very energy inefficiently, that why its only worth it in certain places eg. over production in nuclear power plants or on very small scales such as Labs. The gallium is used as a catalyst for the reaction the pure aluminium is used and turned into aluminium oxide which can be recycled using the over production of power in nuclear power plants. The other key component is the water which is probably better to use distilled but not critical as any mineral deposits can be reprocessed during the recycling of the gallium and alu-oxide. As the distillation process also uses power and quite a lot of it the use of Electolyzer/Electrolysis will not be a big part of the Hydrogen Fuel economy - its not efficient enough. Currently our best hope for cheap carbon effiecnt energy is small scale SSTAR rector's (2015 ish), if you deffo want Hydrogen power then currently the low cost of gallium/alu production seems very good, with very few long term draw backs. IMHO
I just googled a random factlet: It says, refining a gallon of gasoline uses between 4 and 7.5kWh.
So a Model S can go 500 km on 85kWh which means it can go 23.5 km per kWh (assuming refining used 'only' 4kWh) and thus per gallon.
As a comparison, a 2 litre Audi A6 gets 28 MPG. that's about 48 km per gallon.
So you might say, hey, the gas engines are actually better! You'd be wrong.
This means that half the electricity a Model S uses, is used anyway by a gas engine! This means, if we switched over to all electric cars, only 50% of the needed electricity would have to be produced on top of what we're doing today, because the other 50% already go into gas production, right now.
Also, if you take the 7.5kWh number, you get a number of 44 km to the gallon for a Model S and that is RIGHT THERE with what an Audi uses. Only without burning even a cup of fossil fuels.
Sure, a Model S is not magically environmentally friendly. These batteries aren't all fairy dust and laughter to recycle, but heck, I thought CO2 was our major problem. Let's solve it.
Problem is hydrogen sucks as a fuel. It's not just the density/compression and corrosive problem you described. H2 molecules are tiny - about the smallest molecule there is (only a few monoatomic elements are smaller). Tanks and pipes which are watertight and airtight are not necessarily hydrogentight. Storage tanks, delivery trucks and pipelines, and hoses for fueling your car will all leak hydrogen.
Why deal with hydrogen as a fuel with its huge storage, transportation, and delivery problems? Just combine it with some other elements to get a different molecule which is much more manageable at standard temperature and pressure. Most of the focus right now is on methane, but there are liquid compounds as well. The most common is petroleum (which would bring us full circle), but alcohols have nearly as high energy density as gasoline while burning much more cleanly. And you can create alcohol through decomposition and fermentation of plant matter - biofuels.
Hydrogen makes sense for rocket launches because rockets are extremely weight-sensitive, and hydrogen has extraordinarily high energy density per mass. But its volumetric density, corrosive nature, and tendency to leak represent huge engineering challenges for using it as a general purpose fuel. Why bother? So you can brag you're burning a fuel which only produces water as a byproduct? That's only true if you completely ignore the process by which you generate the energy needed to manufacture the hydrogen fuel in the first place.
Actually aluminium does rust. But unlike iron rust, aluminium oxyde produces a solid and stable surface
Your body produces hydrogen peroxide directly in the bloodstream on a fairly regular basis. Nature produces it on a far more regular basis. Rainwater contains hydrogen peroxide. Our body evolved in the presence of this substance. Although it reacts with cells we are talking about seemingly random cells in very tiny quantities and byproduct is oxygen which bonds pretty much immediately with hemoglobin. The body certainly has no trouble replacing cells that belong but won't replace any toxins or byproducts that the peroxide has reacted with.
I'm sure we all know at least one person who takes the stuff regularly for 40+ years. I wouldn't recommend it. Peroxide does kill cells, necessitating replacing cells, increasing the need to replace those cells, and therefore increasing the likelihood of copying errors which lead to aging and possibly even cancer.
That said the idea that short term use of some dilute form of hydrogen peroxide is toxic is ridiculous. Because a few quacks pitched it as a the miracle cure for everything the medical establishment has built the stuff up as the devil. It's a shame because peroxide has many potential internal medical uses. For instance a round of inhaled hydrogen peroxide can help remove tar build-up in a smokers lung. Or a current smoker can use it periodically to help remove the tar their body has difficulty with naturally and possibly stop a great deal of the damage they are doing. Peroxide is definitely a safer route with fewer side-effects than chemo for killing cancer and can even be injected directly into a tumor making it a far more targeted treatment. In small quantities peroxide in the bloodstream acts as sort of molecular polish that reacts with arterial build-up. Like smokers, fast food junkies might be better off having periodic treatments with peroxide than not.
The summary gives the impression that aluminium acts as catalyst in a chemical reaction that produce bubbles of hydrogen by consuming water as fuel. But we know that cannot be true, as that would imply they are extracting energy from an endothermic reaction.
More likely it is actually consuming aluminium as fuel and using water as oxidant. But that is certainly not clearly stated in the summary.
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