Dear Anand and all: Your question below on molecular sieves opened a LARGE box in the attic of my mind.
In 1952 I worked for the Linde Air (oxygen) Company, now Praxis Air. They make and sell liquid nitrogen, oxygen and air by the truckload! My degree is in x-ray crystallography, determining the structure of molecules from their x-ray diffraction patterns. My first job was to understand how oxygen cut steel in a torch process widely used since 1900, but I played bridge at lunchtime with another group working on molecular sieves. One day one partner was missing, so I asked the others what they were working on. They said they were developing "Molecular Sieves". These are three dimensional alumina-silicate minerals now found in nature and manufactured for catalysts. They told me that they hoped to be able to separate oxygen from nirogen using such a sieve. They were successful. One often sees people dragging a small cart which makes 90% oxygen from air for those with difficulty breathing. <><><><> The "A" sieve is one of the most widely used. I asked my friends what the structure of the sieve was. They told me that Linus Pauling was one of their consultants, and that he told them it might take years to work out the structure, and that they would need to have a "single crystal", rather than the powder available. I took this as a challenge, and worked out the structure on my own time. I was given a $5,000 prize by the Liinde Company for the work, and we published in the Journal of the American Chemical Society (JACS) in the mid 1950s. The A sieve has a 10 Angstrom cubic unit cell that has a 6 Angstrom "window" in each of the six faces of the cube. I have 25 lb in my lab that I bought a year ago. I have doped each unit cell with a few atoms of iron, and hope that it will be a superior catalyst for making ammonia (Haber-Bosch process) or oil (Fischer-Tropsch process). I have two colleagues that I sent samples of the sieve for testing, AND I AM WAITING for their reports. If anyone else is interested, write me. Thomas B Reed On Mar 18, 2012, at 12:51 AM, Anand Karve <[email protected]> wrote: > Dear workers of stoves and gasifiers, > when one uses atmospheric air as a source of oxygen, one unnecessarily heats > up the nitrogen in the air. This nitrogen ultimately goes out of the chimney, > taking with it a lot of heat. The technologies based on wood as fuel are > pretty old, but one can revive them, using some of the more recent > techniques. A person who owns a foundry told me that a moleular sieve was now > available for separating nitrogen from oxygen. Has anybody heard of it? Can > it be used in producing a better stove and a better gasifier? > Yours > A.D.Karve > > -- > *** > Dr. A.D. Karve > Trustee & Founder President, Appropriate Rural Technology Institute (ARTI) > > > _______________________________________________ > Gasification mailing list > > to Send a Message to the list, use the email address > [email protected] > > to UNSUBSCRIBE or Change your List Settings use the web page > http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org > > for more Gasifiers, News and Information see our web site: > http://gasifiers.bioenergylists.org/ _______________________________________________ Gasification mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/gasification_lists.bioenergylists.org for more Gasifiers, News and Information see our web site: http://gasifiers.bioenergylists.org/
