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Metal hydrides, with varying degrees of efficiency, can be used as a storage medium for hydrogen, often reversibly. Some are easy-to-fuel liquids at ambient temperature and pressure, others are solids which could be turned into pellets. Proposed hydrides for use in a hydrogen economy include simple hydrides of magnesium or transition metals and complex metal hydrides, typically containing sodium, lithium, or calcium and aluminium or boron. These materials have good energy density by volume, although their energy density by weight is often worse than the leading hydrocarbon fuels. Furthermore, high temperatures are often required to release their hydrogen content.Solid hydride storage is a leading contender for automotive storage. A hydride tank is about three times larger and four times heavier than a gasoline tank holding the same energy. For a standard car, that's about 45 US gallons (0.17 m³) of space and 600 pounds (270 kg) versus 15 US gallons (0.057 m³) and 150 pounds (70 kg). A standard gasoline tank weighs a few dozen pounds (tens of kilograms) and is made of steel costing less than a dollar a pound ($2.20/kg). Lithium, the primary constituent by weight of a hydride storage vessel, currently costs over $40 a pound ($90/kg). Any hydride will need to be recycled or recharged with hydrogen, either on board the automobile or at a recycling plant. A metal-oxide fuel cell, (i.e. zinc-air fuel cell or lithium-air fuel cell), may provide a better use for the added weight, than a hydrogen fuel cell with a metal hydride storage tank.Often hydrides react by combusting rather violently upon exposure to moist air, and are quite toxic to humans in contact with the skin or eyes, hence cumbersome to handle (see borane, lithium aluminum hydride). For this reason, such fuels, despite being proposed and vigorously researched by the space launch industry, have never been used in any actual launch vehicle.Few hydrides provide low reactivity (high safety) and high hydrogen storage densities (above 10% by weight). Leading candidates are sodium borohydride, lithium aluminum hydride and ammonia borane. Sodium borohydride and ammonia borane can be stored as a liquid when mixed with water, but must be stored at very high concentrations to produce desirable hydrogen densities, thus requiring complicated water recycling systems in a fuel cell. As a liquid, sodium borohydride provides the advantage of being able to react directly in a fuel cell, allowing the production of cheaper, more efficient and more powerful fuels cells that do not need platinum catalysts. Recycling sodium borohydride is energy expensive and would require recycling plants. More energy efficient means of recycling sodium borohydride are still experimental. Recycling ammonia borane by any means is still experimental.New Scientist  state that Arizona State University is investigating using a borohydride solution to store hydrogen, which is released when the solution flows over a catalyst made of ruthenium.Hydrogen produced for metal hydride storage must be of a high purity. Contaminants alter the nascent hydride surface and prevent absorption. This limits contaminants to at most 10 ppm oxygen in the hydrogen stream, with carbon monoxide, hydrocarbons and water at very low levels.
NASA is already trying to freeze hydrogen and use it for "slush-hydrogen" engines.
The stuff I was referring to was Dr Roger Billings' blend of Iron and Titanium with a trace of manganese. It sounds much safer and cheaper than some of the stuff you were talking about.
It can store and release hydrogen easily, but slowly. It gives it to the engine as it needs it. However, in the case of a crash it will not blow up like a tank of gasoline would, making it much safer than gasoline or other hydrocarbon fuels.
The Fe Ti blend (Iron and Titanium) would be not toxic. The disadvantage is the weight. It is true that metal hydride is heavy, but compared to tanks of hydrogen at 2,000 psi, it takes much less space.
Also, if you have a fuel cell car, you only need 1/3 of the fuel to go as far as convention gasoline cars. So, even if it weighs more, you only need to store 1/3 of the fuel, so it help cancel that out.
BT, re. "The Hydrogen bonds have lots of energy, it's true. " Actually, hydrogen bonds are relatively weak.
Quote from bored chemist:QuoteBT, re. "The Hydrogen bonds have lots of energy, it's true. " Actually, hydrogen bonds are relatively weak.I'm not a chemist; where could I have got that idea from?I thought it explained the high SHC of water and lots of other things.Certainly Hydrogen has a very high 'calorific value' but I'm not in love with the stuff!
However, in the case of a crash it will not blow up like a tank of gasoline would, making it much safer than gasoline or other hydrocarbon fuels.
Mine was a nonsense question, really, but it does get the whole thing in perspective.The George W. approach seems to want the same rate of consumption yet to improve the situation. Why not just go, in an intelligent way, for drastic reduction in energy use? It doesn't get votes, unfortunately.
that means to reduce the amount humans produce, and have an impact on our standard of living
Quotethat means to reduce the amount humans produce, and have an impact on our standard of livingPrecisely; we either have to do something like it now, voluntarily, or be forced into something more drastic later.Perhaps we need to think differently and not just in terms of "productivity is good". Perhaps "consuming less is good" might get us somewhere.The extreme 'specialism' of the present western society is not many 100 years old. It is changeable - it may have to be. It depends whether we do it early or later.Humans being human, it will probably mean large scale war and a high death rate. There's cheery.
I can't believe that you would just wait for death rather than attempt to get out of the way of an oncoming truck. survival even for an extra day is most people's chosen option.
You haven't answered the question; would you really just stand there? There is only a binary response permitted; yes or no.
I am saying that we need to do something about it soon. The only reasonable something is to use less energy by actually consuming less. It cannot have any adverse effect on out environment so it is a safe direction in which to amble as the truck is on the horizon.
I am also assuming that there is not enough juice in the efficiency lemon to make any significant difference.
Reducing productivity would not be a popular strategy. In fact it is probably impossible to think of it as a likely, voluntary course of action, certainly not for a developing nation. That means heavy persuasion on the part of some powerful nation or group. That's where my war scenario comes in.
So it's a lose lose situation.