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uses of zeolites
commercial and domestic
zeolites are widely used as ion-exchange beds in domestic and commercial water purification,softening,and other applications.in chem**try,zeolites are used to separate molecules(only molecules of certain sizes and shapes can pass through),as traps for molecules so they can be analyzed.
zeolites h**e the potential of providing prec**e and specific separation of gases including the removal of h2o,co2 and so2 from low-grade natural gas streams.other separations include:noble gases,n2,o2,freon and formaldehyde.however at present,the true potential to improve the handling of such gases in th** manner remains unknown.
petrochemical industry
synthetic zeolites are widely used as catalysts in the petrochemical industry,for instance in fluid catalytic cracking and hydro-cracking.zeolites confine molecules in small spaces,which causes changes in their structure and reactivity.the hydrogen form of zeolites(prepared by ion-exchange)are powerful solid-state acids,and can facilitate a host of acid-catalyzed reactions,such as **omer**ation,alkylation,and cracking.catalytic cracking uses a furnace and reactor.first crude oil d**tillation fractions are heated in the furnace and passed to the reactor.in the reactor the crude meets with a catalyst such as zeolite.it goes through th** step three times,each time getting cooler.finally it reaches a step known as separator.the separator collects recycled hydrogen.then it goes through a fractionator and becomes the final item.
nuclear industry
zeolites h**e uses in advanced reprocessing methods,where their micro-porous ability to capture some ions while allowing others to pass freely allow many f**sion products to be efficiently removed from nuclear waste and permanently trapped.equally important are the mineral properties of zeolites.their alumino-silicate construction ** extremely durable and res**tant to radiation even in porous form.additionally,once they are loaded with trapped f**sion products,the zeolite-waste combination can be hot pressed into an extremely durable ceramic form,closing the pores and trapping the waste in a solid stone block.th** ** a waste form factor that greatly reduces its hazard compared to conventional reprocessing systems.
agriculture
in agriculture,clinoptilolite(a naturally occurring zeolite)** used as a soil treatment.it provides a source of slowly released potassium.if previously loaded with ammonium,the zeolite can serve a similar function in the slow release of nitrogen.cuban studies in the emerging field of"zeoponics"suggest that some crops may be grown in 100%zeolite or zeolite mixtures in which the zeolite ** previously loaded or coated with fertilizer and micronutrients.zeolites can also act as water moderators,in which they will absorb up to 55%of their weight in water and slowly release it under plant demand.th** property can prevent root rot and moderate drought cycles.
a potting soil with 12%clinoptilolite was shown to harvest morning dew and return it to the plant roots for reuse.the same bed was able to grow a jerico strain of leaf lettuce in a sub tropical climate without external water and daytime temperatures exceeding 85 °f.th** produce did not bolt and went full term before setting seeds.it also has been shown that certain zeolites can reduce nitrates and nitrites to plant usable free nitrogen by ion exchange.
animal welfare
in concentrated animal growing facilities,the addition of as little as 1%of a very low sodium clinoptiloite was shown to improve feed conversion,reduce airborne ammonia up to 80%,act as a mycotoxin binder and improve bone density.see us patents 4,917,045 and 6,284,232.can be used in general odor elimination for all animal odors.
medical
zeolite-based oxygen concentrator systems are widely used to produce medical grade oxygen.the zeolite ** used as a molecular sieve to create purified oxygen from air using its ability to trap impurities,in a process involving the absorption of undesired gases and other atmospheric components,le**ing highly purified oxygen and up to 5%argon.zeolite was once the active component in quikclot,a hemostatic agent used as an emergency coagulant in the veterinary industry before being found to be toxic.un licensed zeolite-based products are widely sold in the un-regulated alternative health industry.no beneficial result of its use has yet been demonstrated.its miraculous healing properties are attributed to its excitability without apparent cause under microscopic conditions due to‘energy from lay line’transference.
heating and refrigeration
zeolites can be used as solar thermal collectors and for adsorption refrigeration.in these applications,their high heat of adsorption and ability to hydrate and dehydrate while maintaining structural stability ** exploited.th** hygroscopic property coupled with an inherent exothermic reaction when transitioning from a dehydrated to a hydrated form(heat adsorption),make natural zeolites effective in the storage of solar and waste heat energy.
detergents
the largest singel use for zeolite ** the global laundry detergent market.th** amounted to 1.44 million metric tons per year of anhydrous zeolite a in 1992.
construction
synthetic zeolite ** also being used as an additive in the production process of warm mix asphalt concrete.the development of th** application started in europe(germany)in the 1990s.it helps by decreasing the temperature level during manufacture and laying of asphalt concrete,resulting in lower consumption of fossil fuels,thus releasing less carbon dioxide,aerosols and vapours.other than that the usage of synthetic zeolite in hot mixed asphalt leads to easier compaction and to a certain degree allows cold weather p**ing and longer hauls.
when added to portland cement as a pozzolan,it can reduce chloride permeability and improve workability.it reduces weight and helps moderate water content while allowing for slower drying which improves break strength.
gemstones
thomsonites,one of the rarer zeolite minerals,h**e been collected as gemstones from a series of l**a flows along lake superior in minnesota and to a lesser degree in michigan,u.s.a.thomsonite nodules from these areas h**e eroded from basalt l**a flows and are collected on beaches and by scuba divers in lake superior.
these thomsonite nodules h**e concentric rings in combinations of colors,black,white,orange,pink,red and many shades of green.some nodules h**e copper as inclusions and rarely will be found with copper"eyes".when pol**hed by a lapidary the thomsonites sometimes d**play chatoyancy.
aquarium keeping
zeolites are marketed by pet stores for use as a filter additive in aquariums.in aquariums,zeolites can be used to absorb ammonia and other nitrogenous compounds.however,due to the high affinity of some zeolites for calcium,they may be less effective in hard water and may deplete calcium.zeolite filtration ** used in some marine aquaria to keep nutrient concentrations low for the benefit of corals adapted to nutrient-depleted waters.
space hardware testing
zeolites can be used as a molecular sieve in cryosorption pumps for rough pumping of vacuum chambers which can be used to simulate space-like conditions in order to test hardware bound for space.
cat litter
non-clumping cat litter ** often made of zeolite or di**ite.