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Detergents are amphipathic molecules that contain both polar and hydrophobic groups. These molecules contain a polar group (head) at the end of a long hydrophobic carbon chain (tail).
Application in detergency of a low-grade zeolite-a derived from lipari pumice
Researchers in Spain and Sweden have synthesised and structurally determined a new kind of crystalline molecular sieve with extra large holes and chiral properties. Based on zeolite - a microporous crystalline solid - this new structure, which is almost mesoporous, could have many applications including uses in pharmaceutical chemistry, catalysis and separation techniques, say the scientists.
Cuba has exported more than 350 tons of zeolite to Brazil in 2008
Not all zeolites have been studied, but extensive studies have been done on zeolite A due to its use in consumer products. These studies have demonstrated that type A zeolite is essentially non-toxic via oral, dermal, ocular, and respiratory routes of exposure; type A zeolite was also found to be safe for the environment. Please consult the MSDS for product(s) of interest.
The combination of many properties, among them: the microporous character of the uniform pore dimensions, the ion exchange properties, the ability to develop internal acidity, the high thermal stability, the high internal surface area. These make zeolites unique among inorganic oxides.
New natural zeolites are still being discovered, and new synthetic zeolites are being invented in many laboratories around the world.
During the 1930's, R. Barrer and J. Sameshima did extensive work in zeolite synthesis. In 1948, Richard Barrer first produced a synthetic zeolite that did not have a natural counterpart. At approximately the same time, Milton made the first materials that had no natural counterpart such as zeolite A.
Zeolites are available as powders or as formed products such as extrudates. Zeolites, like other solids, are safe to handle and are easy to use in a variety of reactors.
Zeolito estas mineralo, kompleksa akvoriĉa retaluminisiliciato, uzata en industrio kaj kemio (PIV) Zeolito estas aluminio-silikata mineralo kun ĝenerala formulo de M2/nOAl2SiyO2y+4xH2O, kie M estas pozitiva jono (ekz. natria), kiu povas eliĝi aŭ ŝanĝiĝi je aliaj metaljonoj; n estas la valoro de la katjono, y estas 2 aŭ pli; x estas nombro de la akvomolekuloj.La vorto zeolito venas el la greka, ĝin kreis la sveda minerala sciencisto Alex Cronstedt (1722–1765) el grekaj vortoj de zein (bolas) kaj litos (ŝtono).Parto de la zeolitoj estas natura, alia parto estas sinteze konstruita per lesivo, per ardigo de aluminia oksido kaj silicia oksido.