Clinoptilolite
Encyclopedia
Clinoptilolite is a natural zeolite
comprising a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na
,K
,Ca
)2-3Al
3(Al,Si
)2Si13O
36·12(H
2O). It forms as white 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. It commonly occurs as a devitrification
product of volcanic glass shards in tuff
and as vesicle fillings in basalt
s, andesite
s and rhyolite
s. It was described in 1969 from an occurrence in Owl Canyon, San Bernardino County, California
.
Use of clinoptilolite in industry and academia focuses on its ion exchange
properties having a strong exchange affinity for ammonia
(N
H4+). A typical example of this is in its use as an enzyme
based urea
sensor. It is also used as fertiliser, and sold as a deodorizer in the form of pebble-sized chunks contained in a mesh bag.
Research is generally focussed around the shores of the Aegean Sea
due to the abundance of natural clinoptilolite in easily accessible surface deposits.
The name is derived from the Greek words klino (κλίνω;"oblique"), ptylon (φτερών;"feather"), and lithos (λίθος;"stone").
Zeolite
Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents. The term zeolite was originally coined in 1756 by Swedish mineralogist Axel Fredrik Cronstedt, who observed that upon rapidly heating the material stilbite, it produced large amounts of steam from water that...
comprising a microporous arrangement of silica and alumina tetrahedra. It has the complex formula: (Na
Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
,K
Potassium
Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...
,Ca
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
)2-3Al
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
3(Al,Si
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. A tetravalent metalloid, it is less reactive than its chemical analog carbon, the nonmetal directly above it in the periodic table, but more reactive than germanium, the metalloid directly below it in the table...
)2Si13O
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
36·12(H
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
2O). It forms as white to reddish tabular monoclinic tectosilicate
Silicate minerals
The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group...
crystals with a Mohs hardness of 3.5 to 4 and a specific gravity
Specific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...
of 2.1 to 2.2. It commonly occurs as a devitrification
Devitrification
Devitrification is the opposite of vitrification, i.e., the process of crystallization in a formerly crystal-free glass. The term is derived from the Latin vitreus, meaning glassy and transparent.-Devitrification in glass art:...
product of volcanic glass shards in tuff
Tuff
Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...
and as vesicle fillings in basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
s, andesite
Andesite
Andesite is an extrusive igneous, volcanic rock, of intermediate composition, with aphanitic to porphyritic texture. In a general sense, it is the intermediate type between basalt and dacite. The mineral assemblage is typically dominated by plagioclase plus pyroxene and/or hornblende. Magnetite,...
s and rhyolite
Rhyolite
This page is about a volcanic rock. For the ghost town see Rhyolite, Nevada, and for the satellite system, see Rhyolite/Aquacade.Rhyolite is an igneous, volcanic rock, of felsic composition . It may have any texture from glassy to aphanitic to porphyritic...
s. It was described in 1969 from an occurrence in Owl Canyon, San Bernardino County, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
.
Use of clinoptilolite in industry and academia focuses on its ion exchange
Ion exchange
Ion exchange is an exchange of ions between two electrolytes or between an electrolyte solution and a complex. In most cases the term is used to denote the processes of purification, separation, and decontamination of aqueous and other ion-containing solutions with solid polymeric or mineralic 'ion...
properties having a strong exchange affinity for ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
(N
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
H4+). A typical example of this is in its use as an enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
based urea
Urea
Urea or carbamide is an organic compound with the chemical formula CO2. The molecule has two —NH2 groups joined by a carbonyl functional group....
sensor. It is also used as fertiliser, and sold as a deodorizer in the form of pebble-sized chunks contained in a mesh bag.
Research is generally focussed around the shores of the Aegean Sea
Aegean Sea
The Aegean Sea[p] is an elongated embayment of the Mediterranean Sea located between the southern Balkan and Anatolian peninsulas, i.e., between the mainlands of Greece and Turkey. In the north, it is connected to the Marmara Sea and Black Sea by the Dardanelles and Bosporus...
due to the abundance of natural clinoptilolite in easily accessible surface deposits.
The name is derived from the Greek words klino (κλίνω;"oblique"), ptylon (φτερών;"feather"), and lithos (λίθος;"stone").