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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 ...
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]
Clinoptilolite is a natural zeolite composed of a microporous arrangement of silica and alumina tetrahedra. It has the complex formula (Na,K,Ca) 2–3 Al 3 (Al,Si) 2 Si 13 O 36 •12H 2 O. It forms as white, green to reddish tabular monoclinic tectosilicate crystals with a Mohs hardness of 3.5 to 4 and a specific gravity of 2.1 to 2.2.
The typical chemical formula of the unit cell can be described as Q x Na y Al 2.4 Si 33.6 O 72 •zH 2 O (1.4 < x <27)(0.7 < y < 4.3)(1 < z <7), where Q is N,N,N-1-trimethyladamantammonium. [1] The material was patented by Chevron research Company in 1985, [ 3 ] and could potentially be used as a solid catalyst for the methanol -to- olefins ...
Currently zeolites have seen applications in gas separation, membrane reactors, water desalination, and solid state batteries. [2] Currently zeolite membranes have yet to be widely implemented commercially due to key issues including low flux, high cost of production, and defects in the crystal structure.
Mordenite is a zeolite mineral with the chemical formula (Na 2,Ca,K 2) 4 (Al 8 Si 40)O 96 ·28H 2 O. and it is one of the six most abundant zeolites and is used commercially. [3] It was first described in 1864 by Henry How. He named it after the small community of Morden, Nova Scotia, Canada, along the Bay of Fundy, where it was first found.
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.
Pollucite is a zeolite mineral with the formula (Cs,Na) 2 Al 2 Si 4 O 12 ·2H 2 O with iron, calcium, rubidium and potassium as common substituting elements. It is important as a significant ore of caesium and sometimes rubidium. It forms a solid solution series with analcime.