Cold Fusion Experiment

Historically, Cold Fusion experiments involve electrolysis of "heavy water", using at least one electrode made of palladium. There are a lot of people who think it can't work, and even the ones who do think it can work admit that there are significant problems in getting it to work reliably. However, in the last few years an alternate technique for doing Cold Fusion experiments has apparently been very reliable, and has even been published in a major physics journal (see link). The Idea here is to build upon that technique.

The alternate technique simply takes deuterium gas (the variety of hydrogen that makes heavy water "heavy") and directly pressurize it into palladium metal. Proponents note that in an electrolysis experiment, you have to wait for an appropriate quantity of deuterium to seep into the metal, before anything interesting happens -- but in this approach, the waiting time is diminished drastically. And certain things that were thought to be important in an electrolysis experiment, like irregularities in the crystalline microstructure of the electrode metal, become irrelevant. (Not to mention that those irregularities are difficult to duplicate and could also explain the unreliability of the original experiments.)

Now it happens that palladium is a rather expensive metal, which means that if Cold Fusion is real, and can someday be employed on a large scale, then there just isn't enough of the metal available to meet the demand that will be associated with lots of CF power plants around the world. It is very importent to find out if any other metal can work. Reports that I've encountered indicate that titanium or nickel might work, but more research is needed.

In THIS experiment, the metal chosen is mercury. It is common enough that small amounts have been used in billions of fluorescent light bulbs over the past several decades. It is also toxic, meaning that when all those light bulbs die, the mercury should be recycled, instead of being allowed to seep into the environment from a landfill. If it could be used in a Cold Fusion power plant, it would not be "used up" --a fixed quantity would simply continue to be used for a long long time.

Mercury has a particular property that would be very convenient for a CF reactor, and this is the fact that it is a liquid at room temperature. See, if Cold Fusion of deuterium can happen inside SOME metal, then the result will be the formation of atoms of helium. But inside solid metal, the helium is stuck and eventually would interfere with the fusion reaction rate, meaning that after a while the solid metal has to be removed from the reactor, and processed/purified to get the helium out. But since mercury is a liquid, any helium can simply bubble out, meaning that the mercury never needs to be repurified.

It is to be noted that if CF can work in other metals, well, at a high enough temperature any of them could be liquid, and so why use mercury? Well, this Idea is about an EXPERIMENT more than it is about an invention, and the experiment is to find out if CF can happen inside liquid metal. It should be obvious that the experiment would be simpler and less expensive if it could be performed at room temperature. (Not to mention that some of those other metals, which happen to melt at a reasonably low temperature, like sodium, chemically react with hydrogen, while mercury doesn't.)

One known fact is that while hydrogen is able to penetrate a number of metals (it penetrates palladium best of all), mercury is not normally one of them. This could simply be a result of the fact that mercury is usually a liquid, and so hydrogen can bubble out as easily as helium might --being a liquid also makes it difficult to construct a kind of sheet-metal barrier out of mercury, the way they test other metals to see if hydrogen can permeate through them. On the other hand, there is some evidence that when mercury is used as an electrolysis electrode, small amounts of atomic hydrogen (produced by the electrolysis process) can permeate the liquid metal...(see link).

Well, anyway, to whatever degree hydrogen might naturally be able to penetrate mercury, the whole point of using pressurized gas is to increase the amount that penetrates it. So, Item One in this Experiment is a reasonably strong pressure chamber, made out of materials that can effectively resist permeation by hydrogen (glass is good).

Next, we want to put a slightly special centrifuge inside this pressure chamber. The rationale for this comes from some other data that has recently been discussed by Cold Fusion researchers. There are claims being made that when CF happens, it usually happens close to the surface of the metal, perhaps no more than 25 microns (millionths of a meter) from the actual surface. If true, this could be good because even if we used palladium only, we may only need to use very thin foil (will cost less).

Back to mercury. Anyone who has seen a blob of mercury on a flat surface knows that the blob always has a significant thickness to it (about three millimeters, if I recall right). Well, mercury isn't so cheap that if all we need is, say, a 30-micron film, there is no reason to let it naturally be a hundred times as thick. A centrifuge can be used to flatten it out!

For the purposes of this Experiment, it is not really necessary to use a centrifuge. But I wanted to describe how to do so in case there is a desire to Scale Up the experiment for power-production purposes, to the point where using thin films of mercury would reduce the total cost.

Basically, this centrifuge could be mostly shaped like a spinning barrel. Here's an ASCII sketch of PART of its cross section:
__ |__(top)
|
|
|
|_| | |_|
Oriented vertically, the vertical bars in the middle of the top and bottom parts of the sketch represent the axle. The |_| shape at the bottom is a ring around that axle, kind of like a cake mould that has a hole in its center, and is where we put the mercury before we turn the centrifuge on. The other vertical bars at the left are the wall of the barrel, and would be matched by more bars at the right in the sketch, if only I could use a fixed font to line up the vertical bars at the right. When the centrifuge spins up, this wall becomes the "bottom", such that the mercury will flow onto it and spread itself thin, depending on how fast the centrifuge spins. The horizontal line marked "(top)" then becomes a wall that prevents the mercury from escaping there from the centrifuge barrel.

With the entire centrifuge inside the pressure chamber, we can spin it up before we start presurizing the chamber with deuterium gas. When the mercury has spread into a thin film inside the barrel-wall, then we start pumping in the deuterium. One thing to be wary about is the fact that the extra pressure will mean that there is extra friction between the spinning centrifuge and the gas in the pressure chamber. It should be expected to complicate the energy measurements of any CF reactions that occur. (That's another reason why it might be best to not use a centrifuge in the Experiment.)

On the other hand, we could simply let the experiment run for a couple of weeks, and not worry at all about any energy production (don't even try to measure it), after which we carefully extract the deuterium gas and look to see if any helium is in there. If there is any more helium present than can be explained by the existing natural "background" (helium is a tiny part of the Earth's atmosphere), then that would be evidence that CF had occurred during the experiment. Simple!