molecular sieve is a cubic lattice of an aluminosilicate compound having. Molecular sieve has a uniform porous structure, the diameter of its pores of uniform size, these cavities can adsorb molecules smaller diameter than the internal bore, and an unsaturated polar molecules and molecules having a preferential adsorption capacity, and thus able to very different degree, different degree of saturation, and boiling points of different molecular sizes of different molecules separated, that has the effect of "screening" elements, so called zeochem molecular sieves Since the molecular sieves have a high adsorption capacity, high thermal stability other adsorbents that are not so widely applied molecular sieve.
In the field of biological macromolecules, a common bio-rad SEC sieve prepacked columns.
US scientists have found that by adjusting the temperature, to precisely control one titanium silicate material pore size, to create a sophisticated molecular sieve. Some internal crystal material has a large number of uniform pore size smaller than the molecules can pass through the holes, while large molecules can not pass through, and thus serves to separate different molecules, such materials are known as air separate unit molecular sieve adsorbent.
In fact, in 2001, scientists in the UK "Nature" magazine reported that they had discovered a titanium silicate material known as ETS-4 can be used as a good molecular sieve. When the temperature rises, ETS-4 will gradually dehydrated, pore size decreases. Finely adjust the pore size in the use of this method, (1 angstrom equals one billion of a meter) in the 3-4 Angstroms range. Scientists say some common elements such as nitrogen, methane, oxygen, argon and water molecules are about the size of 3-4 Å, another is almost the same size, molecular sieves drying made with ETS-4 can effectively separate them. Researchers have experimented with ETS-4 from the nitrogen content in the mixture of nitrogen and methane, from 18% to 5%, and in the separation of argon and oxygen, nitrogen and oxygen experiments have been successful. It is believed that this technology will have important commercial applications
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