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Group of Microbes Change Dissolved Gold to Solid
option8 writes " National Geographic, has a an article about a newly discovered strain of bacteria that might be used (though, as the article says, not cost-effectively) to harvest gold and other metals from seawater - a longtime fantasy of science fiction."
gold as a mineral isnt rare. for instance in sea water. only problem it is distributed widely in solution in minute quantities per gram. I read some years ago about mine dumps leaching metals, the problem was tackled by using some specialised bacteria. so using bacteria to concentrate metals is not new. seabed nodules are made by bacteria which gollect Nickel. but this takes thousands of years. by pumping sea water over beds of bacteria in factories the concentration of gold could be increased.
As the article mentioned, microbes are already used to clean up toxic water by eating dangerous heavy metals, and research has been done into the processes and genes responsible. Perhaps the genes could be switched into something land based, like a fast growing moss or other plant. Imagine if a company could make more money by covering old leaky strip mines with plants, then just harvesting them!
I can't imagine people can live satisfied doing this kind of work. Dammit learn to program
Who says that the biologists don't already know how to program? Quite a few biologists consider programming (or at least scripting) an essential skill these days -- analyzing thousands of pieces of data by hand is no fun. And as for job satisfaction, contributing to the knowledge of humanity is way more satisfying than working for some soon to be defunct Web portal...
... of something I saw on the Discovery Channel. Apparently after invading Spain the Romans wanted to extract the gold inside of a mountian. So what they did was order their slaves to dig a winding maze of tunnels through the mountain. Then the romans unleashed a river to run through the mountain. This effectively destroyed the mountain and stripped out all the gold. The water then flowed into a plain which held Marygolds I think, it some yellow flower anyways.
You don't exist. Go away. --SysVinit Halt
See, they are useful anyway.
Don't post innacurate information
If you do, I swear by my pretty floral bonnet I will end you.
Metals have been produced from seawater for decades, and very economically, too. There are several which can be practically produced this way. But of that group, the only common *structural* metal which I can think of is Magnesium.
Magnesium hydroxide can be cheaply extracted from brine by precipitation when a cheap alkali is added - usually slaked lime (calcium hydroxide). The magnesium hydroxide becomes the feedstock for electrolytic cells which produce metallic magnesium. This second step is similar to the way that metallic aluminum is produced from aluminum hydroxide, after it is refined from bauxite. At one time, most of the world's magnesium was produced this way, though it may or may not be now - there are other practical sources. It is sufficient to say that the cost of electrolysis for magnesium production greatly outweighs the cost of the hydroxide feedstock, regardless of the source.
Uranium can also be produced from seawater, by various methods, but the cost is very much higher than either current world prices (very low right now) or even historical peak prices. It *is* however, *definitely* not too expensive for breeder reactor usage (breeders yield ~100 times more energy per unit mass of natural uranium). And there is something like 500 - 1000 times more uranium dissolved in seawater than all current, proven reserves in conventional mines.
In addition, I believe several other, non-structural metals are or can be produced from seawater. Rubidium, cesium, strontium, barium are perhaps possible. The amounts available is *usually* vastly larger than mine reserves.
Clearly, calling metal extraction from seawater "science fiction" is quite inappropriate.
-- Mike Greaves