Search results
Results from the WOW.Com Content Network
Zeolite exhibited in the Estonian Museum of Natural History. Zeolite is a group of several microporous, crystalline aluminosilicate minerals commonly used as commercial adsorbents and catalysts. [1] They mainly consist of silicon, aluminium, oxygen, and have the general formula M n+ 1/n (AlO 2) − (SiO 2) x ･y H 2 O where M n+ 1/n is either ...
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
[a] Many kinds of materials exhibit some molecular sieves, but zeolites dominate the field. Zeolites are almost always aluminosilicates, or variants where some or all of the Si or Al centers are replaced by similarly charged elements. [2]
Since the metal-imidazole-metal angle is similar to the 145° Si-O-Si angle in zeolites, ZIFs have zeolite-like topologies. [2] As of 2010, 105 ZIF topologies have been reported in the literature. [ 3 ] [ 4 ] Due to their robust porosity, resistance to thermal changes, and chemical stability, ZIFs are being investigated for applications such as ...
Faujasite (FAU-type zeolite) is a mineral group in the zeolite family of silicate minerals.The group consists of faujasite-Na, faujasite-Mg and faujasite-Ca. They all share the same basic formula (Na 2,Ca,Mg) 3.5 [Al 7 Si 17 O 48]·32(H 2 O) by varying the amounts of sodium, magnesium and calcium. [1]
A zeolite membrane is a synthetic membrane made of crystalline aluminosilicate materials, typically aluminum, silicon, and oxygen with positive counterions such as Na + and Ca 2+ within the structure. Zeolite membranes serve as a low energy separation method.
The ferrierite group of zeolite minerals (the FER structure) consists of four very similar species: ferrierite-Mg, ferrierite-Na, ferrierite-NH4 and ferrierite-K, based on the dominant cation in the A location. ferrierite-Mg and ferrierite-K are orthorhombic minerals and ferrierite-Na is monoclinic with highly variable cationic composition (Na,K) 2 Mg(Si,Al) 18 O 36 (OH)·9H 2 O.
Pentasil-zeolites are defined by their structure type, and more specifically by their X-ray diffraction patterns. ZSM -5 is the trade name of a pentasil-zeolite. As early as 1967, Argauer and Landolt worked out parameters for the synthesis of pentasilzeolites, particularly those relating to the following molar ratios: OH − /SiO 2 = 0.07–10, SiO 2 /Al 2 O 3 = 5–100, H 2 O/SiO 2 = 1–240. [1]