|How do we extract Helium (symbol = He) from the
|Question Date: 1999-03-03|
Cool air down to several degrees Kelvin...as the
temp. drops from room temp.,different gases will
condense at different temps. For example, the
diatomic nitrogen (N2) will condense at around 75
Kelvin, oxygen at 96 K (i think, but i know where
to look this up if i needed to know it exactly) .
He condenses at just a few degress above absolute
zero. you can look up its one atmosphere
condensation point in a book. look up helium in a
REFERENCE book (ENCARTA??)
That's a good question.I'm not sure of the answer
, but I have a guess. Let's see if we can help
each other out. For starters, did you know that
air is made up of different gases like nitrogen,
oxygen, carbon dioxide and helium? Also, did you
know that each of these gases will turn into
liquid if you cool them enough (carbon dioxide is
a little strange, but we won't talk about that)?
It's true...if you take oxygen gas an make it
really really cold, it will turn into liquid
oxygen. The same is true of nitrogen. Squeezing
the gases really really hard will do the same
thing....turn the gases into lquids.
now we know that gases can turn into liquids. Did
you also know that each gas has it's own
temperature at which is turns from a gas to a
liquid? Did you also know that turning helium
into a liquid needs the lowest temperature? That
means if we take air (which is made of mainly of
nitrogen, oxygen, carbon dioixde and helium) and
make it really cold the gases will turn into
liquids. First, I think it starts with carbon
dioxide (at -78 degrees Celsius), oxygen (at -182
degrees Celsius), and then nitrogen (at -195
degrees Celsius). At -195 degrees Celsius, the
other main gases are all liquids and you can pour
them out the bottom of your container. 99% of the
gas that's left is helium (since it turns to
liquid at -268 degress Celsius, -195 degrees
Celsius is still really warm for Helium).
that's my guess. I'm pretty sure that cooling air
down to -195 degrees Celsius would work, leaving
helium as the major gas that's left. Of course,
maybe there's a cheaper way to do it. Did you
know that there are companies which specialize in
extracting helium and other gases from the
atmosphere? One of the biggest companies that
does this is called PraxAir. I bet you could find
them on the web if you searched under "helium gas"
or "liquid nitrogen." Why don't you try and find
them and see if our answer is correct!
Helium is not extracted from the atmosphere. It
is separated from natural gas in oil & gas
drilling operations. I don't know what methods
are specifically used but one example of gas
separation technology is microporous membranes.
Look up these words in a dictionary if you want to
know what this is: "micro", "porous", and
"membrane". There is a lot of information on the
internet if you want to know more.
I think I have an answer regarding the He
question. From my understanding, He is usually
purified from natural gas deposits in the course
of refining. There is little He in the atmosphere
as it has such a low density it tends to dissipate
into space. However, He is a common product of
radioactive decay of uranium to lead, and the He
tends to accumulate in the same natural reserviors
underground in which natural gas is found.
I don't think anyone does. The amount of helium
in the atmosphere is too small. Instead, helium,
I believe, is recovered where oil is found.
Somehow, helium slowly collects in these places
over time as heavy elements radioactively decay.
When people drill for oil they can recover the
helium that's trapped with the oil.
gases can be recovered from the atmosphere. One
easy way to do this is to liquify and separate out
various gases from air such as nitrogen, oxygen,
Click Here to return to the search form.
Copyright © 2017 The Regents of the University of California,
All Rights Reserved.