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2021/08/01
2021/07/19
Xiamen Zeolitemin Biotech Co.,Ltd.: Feed Grade Zeolite in Animal Husbandry
Xiamen Zeolitemin Biotech Co.,Ltd.: Feed Grade Zeolite in Animal Husbandry: Feed grade zeolite powder plays a very important role in the animal husbandry industry. Used as feed (cattle, pig, chicken) additives ...
2009/04/26
南美西岸航线介绍（城市与港口 港口与船公司）
南美西岸航线:
国家与基本港口城市介绍：
COLOMBIA 哥伦比亚
基本港：BUENAVENTURA 布埃纳文图拉， 其他港口城市：BOGOTA 波哥大
ECUADOR 厄瓜多尔
基本港：GUAYAQUIL 瓜亚基尔， 其他港口城市：CUENCA 昆卡，MANTA 曼塔，QUITO 基多，ESMERALDS
PERU 秘鲁
基本港：CALLAO 卡亚俄， 其他港口城市ILO 依洛，LIMA 利马，PAITA 派塔
BOLIVIA 玻利维亚
LA PAZ 拉帕斯(CAP)，COCHABAMBA，SANTA CRUZ
CHILE 智利
基本港：IQUIQUE 伊基克，SAN ANTONIO 圣安东尼奥 ，VALPARAISO 瓦尔帕来索， 其他港口城市：ARICA 阿里卡 ，ANTOFAGASTA 安托法加斯塔，CONCEPCION，COQUIMBO，LIRQUEN 立昆，PENCO，PUERTO MONTT，PUNTA ARENAS 蓬塔阿雷纳斯，SAN VINCENTE 圣文森特，SANTIAGO 圣地亚哥，TALCAHUANO 塔尔卡华诺
宁波，上海港口南美西岸航线各大船公司介绍：
长荣 EVERGREEN （台湾） 船期：每周一，每周二，每周六（周一小船，经香港中转接二程船到科隆，接三程船到南美各基本港口，如到其他港口再中转。周二船多数用ZIM的舱位所以对于旺季的时候上船比较难控制，很可能被ZIM 甩箱，到达科隆后中转。周六的船长荣自己的船，由于挂靠美国所以需要发送AMS。对于三方贸易比较麻烦。到达科隆以后中转） 优势：市场价格比较便宜，他们永远会走在降价的前列。往往会比市场价格最低的。 缺点：时间较长，对于要求船期的客户我建议不要使用此公司船。对于哥伦比亚，秘鲁的港口稍微好点，智利的港口时间是相对较长的。一旦中转港压港对于你的货物何时中转，更本无法控制。对于因此带来的损失只有你自己承担。
CSAV 南美邮轮 （智利） 船期：没有固定的船期，每个月提供下月大致船期。开航日不稳定。 挂靠基本港：CALLAO , IQUIQUE, ANTOFAGASTA , SAN ANTONIO 隔周直达：BUENAVENTURA, GUAYAQUIL 优点：智利的船公司，对于智利的收货人有一定的清和力。部分港口直达，对于航程可以控制。多位船东提单。 缺点：南美部分港口不能直达，开航日不固定，上海港口的服务欠缺。 MARUBA. 马鲁巴 （阿根廷） 船期：每周一 （中海，CMA, 共舱） 直达挂靠基本港：BUENAVENTURA, CALLAO, SAN ANTONIO 直达挂靠港口较少。多为船东提单。
中海 （中国）2006年3月21日南美西岸首航 船期：每周一 （MARUBA，CMA, 共舱） 直达挂靠基本港：BUENAVENTURA, CALLAO, SAN ANTONIO 直达挂靠港口较少。多为船东提单。
NYK 日本邮轮 （日本） 船期：每周五 直达挂靠基本港： BUENAVENTURA ,GUAYAQUIL,CALLAO,IQUIQUE, VALPARAISO 直达挂靠基本港较多，但也因此挂靠到末港VALPARAISO时航程较长。市场上多为船东提单。
MSC 地中海航运 船期：每周三 直达挂靠港口：BUENAVENTURA, IQUIQUE, SAN ANTONIO 直达港口较少，市场上目前多为代理提单。价格略微便宜。服务质量欠缺。
CCNI 智利国航 （智利） 船期：每周一，每周五 周一直达港口：CALLAO , IQUIQUE, VALPARAISO, LIRQUEN 周五直达港口：BUENAVE,GUAYAGUIL,CALLAO,SAN ANTONIO 直达挂靠港口较多，船期航程比较稳定，南美西岸有十分强大的实力。对于南美的客户有较大的清和力。
HAM 汉堡南美 （CCNI 共舱） 船期：每周一，每周五 周一直达港口：CALLAO , IQUIQUE, VALPARAISO, LIRQUEN 周五直达港口：BUENAVE,GUAYAGUIL,CALLAO,SAN ANTONIO
其他各大船公司（TMM, CMA, 等）在此不一一介绍。如有需要可具体询问。 更多加勒比海，中美洲，各大船公司在以后的时间里会为大家一一介绍
国家与基本港口城市介绍：
COLOMBIA 哥伦比亚
基本港：BUENAVENTURA 布埃纳文图拉， 其他港口城市：BOGOTA 波哥大
ECUADOR 厄瓜多尔
基本港：GUAYAQUIL 瓜亚基尔， 其他港口城市：CUENCA 昆卡，MANTA 曼塔，QUITO 基多，ESMERALDS
PERU 秘鲁
基本港：CALLAO 卡亚俄， 其他港口城市ILO 依洛，LIMA 利马，PAITA 派塔
BOLIVIA 玻利维亚
LA PAZ 拉帕斯(CAP)，COCHABAMBA，SANTA CRUZ
CHILE 智利
基本港：IQUIQUE 伊基克，SAN ANTONIO 圣安东尼奥 ，VALPARAISO 瓦尔帕来索， 其他港口城市：ARICA 阿里卡 ，ANTOFAGASTA 安托法加斯塔，CONCEPCION，COQUIMBO，LIRQUEN 立昆，PENCO，PUERTO MONTT，PUNTA ARENAS 蓬塔阿雷纳斯，SAN VINCENTE 圣文森特，SANTIAGO 圣地亚哥，TALCAHUANO 塔尔卡华诺
宁波，上海港口南美西岸航线各大船公司介绍：
长荣 EVERGREEN （台湾） 船期：每周一，每周二，每周六（周一小船，经香港中转接二程船到科隆，接三程船到南美各基本港口，如到其他港口再中转。周二船多数用ZIM的舱位所以对于旺季的时候上船比较难控制，很可能被ZIM 甩箱，到达科隆后中转。周六的船长荣自己的船，由于挂靠美国所以需要发送AMS。对于三方贸易比较麻烦。到达科隆以后中转） 优势：市场价格比较便宜，他们永远会走在降价的前列。往往会比市场价格最低的。 缺点：时间较长，对于要求船期的客户我建议不要使用此公司船。对于哥伦比亚，秘鲁的港口稍微好点，智利的港口时间是相对较长的。一旦中转港压港对于你的货物何时中转，更本无法控制。对于因此带来的损失只有你自己承担。
CSAV 南美邮轮 （智利） 船期：没有固定的船期，每个月提供下月大致船期。开航日不稳定。 挂靠基本港：CALLAO , IQUIQUE, ANTOFAGASTA , SAN ANTONIO 隔周直达：BUENAVENTURA, GUAYAQUIL 优点：智利的船公司，对于智利的收货人有一定的清和力。部分港口直达，对于航程可以控制。多位船东提单。 缺点：南美部分港口不能直达，开航日不固定，上海港口的服务欠缺。 MARUBA. 马鲁巴 （阿根廷） 船期：每周一 （中海，CMA, 共舱） 直达挂靠基本港：BUENAVENTURA, CALLAO, SAN ANTONIO 直达挂靠港口较少。多为船东提单。
中海 （中国）2006年3月21日南美西岸首航 船期：每周一 （MARUBA，CMA, 共舱） 直达挂靠基本港：BUENAVENTURA, CALLAO, SAN ANTONIO 直达挂靠港口较少。多为船东提单。
NYK 日本邮轮 （日本） 船期：每周五 直达挂靠基本港： BUENAVENTURA ,GUAYAQUIL,CALLAO,IQUIQUE, VALPARAISO 直达挂靠基本港较多，但也因此挂靠到末港VALPARAISO时航程较长。市场上多为船东提单。
MSC 地中海航运 船期：每周三 直达挂靠港口：BUENAVENTURA, IQUIQUE, SAN ANTONIO 直达港口较少，市场上目前多为代理提单。价格略微便宜。服务质量欠缺。
CCNI 智利国航 （智利） 船期：每周一，每周五 周一直达港口：CALLAO , IQUIQUE, VALPARAISO, LIRQUEN 周五直达港口：BUENAVE,GUAYAGUIL,CALLAO,SAN ANTONIO 直达挂靠港口较多，船期航程比较稳定，南美西岸有十分强大的实力。对于南美的客户有较大的清和力。
HAM 汉堡南美 （CCNI 共舱） 船期：每周一，每周五 周一直达港口：CALLAO , IQUIQUE, VALPARAISO, LIRQUEN 周五直达港口：BUENAVE,GUAYAGUIL,CALLAO,SAN ANTONIO
其他各大船公司（TMM, CMA, 等）在此不一一介绍。如有需要可具体询问。 更多加勒比海，中美洲，各大船公司在以后的时间里会为大家一一介绍
2009/01/14
Zeolite Detergent Grade Series
ADVAN® Synthetic detergent zeolites, are the principle alternative to phosphate type builders, used in household detergents and softening the washing water by calcium ion exchange. The major part of phosphate-free household detergents is based on the use of Zeolite as builder.
Properties
General Type
Ignition weightlessness 800 º C ， 1h : 20 ± 1%
Calcium Exchanging Rate ( mgCaCO3/g ) : 320 ± 10 ≥ 170>200
2 Minutes ( mgCaCO3/g )
10 Minutes
PH Value(1% ， 25 º C) <11 w="Y10">
<4um>
<1um>
Bulk density ( g/l ) 500-600
Bulk Density ( g/l ) 300-450
More information:
ADVAN® Synthetic detergent zeolites, are the principle alternative to phosphate type builders, used in household detergents and softening the washing water by calcium ion exchange.
The major part of phosphate-free household detergents is based on the use of Zeolite A as builder.
As a detergent builder, Zeolite A was developed specifically as an environmentally preferable alternative to phosphate builders, which can cause eutrophication of freshwater bodies by nourishing excessive amounts of algae.Zeolites possess a number of advantages over other builders during the production of detergents. With regards, zeolites display a very high product stability, regardless of the particular process employed (spray drying, granulation, extrusion etc). They prove inert when exposed to elevated temperatures, mechanical influences or alkalinity.The high flexibility of zeolites with respect to formulation and ease of processing together with the economic advantage of the raw material have led to it becoming an extremely attractive builder.
Link: http://www.xmzeolite.com
Properties
General Type
Ignition weightlessness 800 º C ， 1h : 20 ± 1%
Calcium Exchanging Rate ( mgCaCO3/g ) : 320 ± 10 ≥ 170>200
2 Minutes ( mgCaCO3/g )
10 Minutes
PH Value(1% ， 25 º C) <11 w="Y10">
<4um>
<1um>
Bulk density ( g/l ) 500-600
Bulk Density ( g/l ) 300-450
More information:
ADVAN® Synthetic detergent zeolites, are the principle alternative to phosphate type builders, used in household detergents and softening the washing water by calcium ion exchange.
The major part of phosphate-free household detergents is based on the use of Zeolite A as builder.
As a detergent builder, Zeolite A was developed specifically as an environmentally preferable alternative to phosphate builders, which can cause eutrophication of freshwater bodies by nourishing excessive amounts of algae.Zeolites possess a number of advantages over other builders during the production of detergents. With regards, zeolites display a very high product stability, regardless of the particular process employed (spray drying, granulation, extrusion etc). They prove inert when exposed to elevated temperatures, mechanical influences or alkalinity.The high flexibility of zeolites with respect to formulation and ease of processing together with the economic advantage of the raw material have led to it becoming an extremely attractive builder.
Link: http://www.xmzeolite.com
Zeolite Detergent Grade
From Wikipedia, the free encyclopedia
Zeolites (Greek, zein, "to boil"; lithos, "a stone") are aluminosilicate minerals and have a microporous structure (pores smaller than 2 nm).
The term zeolite was originally coined in the 18th century by Swedish mineralogist Axel Fredrik Cronstedt, who observed that upon rapidly heating a natural mineral, the stones began to dance about. Using the Greek words which mean "stone that boils," he called this material zeolite. The stones "boiled" because the water adsorbed inside the zeolite's pores was driven off by heating.
More than 175 unique zeolite frameworks have been identified, and 48 naturally occurring zeolites are known. zeolites have a porous structure that can accommodate a wide variety of cations, such as Na+, K+, Ca2+, Mg2+ and others. These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are: analcime, chabazite, heulandite, natrolite, phillipsite, and stilbite. An example mineral formula is: Na2Al2Si3O10-2H2O, the formula for natrolite.
Natural zeolites form where volcanic rocks and ash layers react with alkaline groundwater. zeolites also crystallize in post-depositional environments over periods ranging from thousands to millions of years in shallow marine basins. Naturally occurring zeolites are rarely pure and are contaminated to varying degrees by other minerals, metals, quartz, or other zeolites. For this reason, naturally occurring zeolites are excluded from many important commercial applications where uniformity and purity are essential.
zeolites are the aluminosilicate members of the family of microporous solids known as "molecular sieves." The term molecular sieve refers to a particular property of these materials, i.e. the ability to selectively sort molecules based primarily on a size exclusion process. This is due to a very regular pore structure of molecular dimensions. The maximum size of the molecular or ionic species that can enter the pores of a zeolite is controlled by the dimensions of the channels. These are conventionally defined by the ring size of the aperture, where, for example, the term "8-ring" refers to a closed loop that is built from 8 tetrahedrally coordinated silicon (or aluminum) atoms and 8 oxygen atoms. These rings are not always perfectly symmetrical due to a variety of effects, including strain induced by the bonding between units that are needed to produce the overall structure, or coordination of some of the oxygen atoms of the rings to cations within the structure. Therefore, the pores in many zeolites are not cylindrical.
Sources
Conventional open pit mining techniques in Arkansas are used to mine natural zeolites. The overburden is removed to allow access to the ore. The ore may be blasted or stripped for processing by using tractors equipped with ripper blades and front-end loaders. In processing, the ore is crushed, dried, and milled. The milled ore may be air-classified as to particle size and shipped in bags or bulk. The crushed product may be screened to remove fine material when a granular product is required, and some pelletized products are produced from fine material. Producers also may modify the properties of the zeolite or blend their zeolite products with other materials before sale to enhance their performance.
Currently, the world’s annual production of natural zeolite is about 4 million tons. Of this quantity, 2.6 million tons are shipped to Chinese markets to be used in the concrete industry. Eastern Europe, Western Europe, Australia, and Asia are world leaders in supplying the world’s demand for natural zeolite. By comparison, only 57,400 metric tons (source: U.S. Geological Survey, 2004) of zeolite (only 1% of the world’s current production) is produced in North America; only recently has North America realized the potential for current and future markets.
There are several types of synthetic zeolites that form by a process of slow crystallization of a silica-alumina gel in the presence of alkalis and organic templates. One of the important processes used to carry out zeolite synthesis is sol-gel processing. The product properties depend on reaction mixture composition, pH of the system, operating temperature, pre-reaction 'seeding' time, reaction time as well as the templates used. In sol-gel process, other elements (metals, metal oxides) can be easily incorporated. The silicalite sol formed by the hydrothermal method is very stable. Also the ease of scaling up this process makes it a favorite route for zeolite synthesis.
Synthetic zeolites hold some key advantages over their natural analogs. The synthetics can, of course, be manufactured in a uniform, phase-pure state. It is also possible to manufacture desirable zeolite structures which do not appear in nature. zeolite A is a well-known example. Since the principal raw materials used to manufacture zeolites are silica and alumina, which are among the most abundant mineral components on earth, the potential to supply zeolites is virtually unlimited. Finally, zeolite manufacturing processes engineered by man require significantly less time than the 50 to 50,000 years prescribed by nature. Disadvantages include the inability to create crystals with dimensions of a comparable size to their natural counterparts.
Uses
Commercial and Domestic
zeolites are widely used as ion-exchange beds in domestic and commercial water purification, softening, and other applications. In chemistry, 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 have the potential of providing precise 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 this 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 isomerisation, alkylation, and cracking. The specific activation modality of most zeolitic catalysts used in petrochemical applications involves quantum-chemical Lewis acid site reactions. Catalytic cracking uses a furnace and reactor. First crude oil distillation 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 this 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 have uses in advanced reprocessing methods, where their micro-porous ability to capture some ions while allowing others to pass freely allow many fission products to be efficiently removed from nuclear waste and permanently trapped. Equally important are the mineral properties of zeolites. Their alumino-silicate construction is extremely durable and resistant to radiation even in porous form. Additionally, once they are loaded with trapped fission 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. This is a waste form factor that greatly reduces its hazard compared to conventional reprocessing systems.
Agriculture
In agriculture, clinoptilolite (a naturally occurring zeolite) is 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. zeolite 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. This property can prevent root rot and moderate drought cycles.
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 is 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, leaving highly purified oxygen and up to 5% argon. QuikClot® brand hemostatic agent, which continues to be used successfully to save lives by stopping severe bleeding, contains a calcium loaded form of zeolite.
Heating and refrigeration
zeolite 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 is exploited. This hygroscopic property coupled with an inherent exothermic (heat producing) reaction when transitioning from a dehydrated to a hydrated form, make natural zeolite useful in harvesting waste heat and solar heat energy.
Detergents
The largest single use for zeolite is the global laundry detergent market. This amounted to 1.44 million metric tons per year of anhydrous zeolite A in 1992.
Construction
Synthetic zeolite is also being used as an additive in the production process of warm mix asphalt concrete. The development of this 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 paving 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, have been collected as gemstones from a series of lava flows along Lake Superior in Minnesota and to a lesser degree in Michigan, U.S.A.. Thomsonite nodules from these areas have eroded from basalt lava flows and are collected on beaches and by scuba divers in Lake Superior.
These thomsonite nodules have concentric rings in combinations of colors, black, white, orange, pink, red and many shades of green. Some nodules have copper as inclusions and rarely will be found with copper "eyes". When polished by a lapidary the thomsonites sometimes display chatoyancy
Aquarium keeping
zeolite are marketed by pet stores for use as a filter additive in aquariums. In aquariums, zeolite can be used to absorb ammonia and other nitrogenous compounds. However, due to the high affinity of some zeolite for calcium, they may be less effective in hard water and may deplete calcium. Zeolite filtration is used in some marine aquaria to keep nutrient concentrations low for the benefit of corals adapted to nutrient-depleted waters.
Where and how the zeolite was formed is an important consideration for aquariums. Northern hemisphere natural zeolite were formed when molten lava came in contact with sea water, thereby 'loading' the zeolite with Na (sodium) sacrificial ions. These sodium ions will speciate with other ions in solution, thus the takeup of nitrogen in ammonia, with the release of the sodium. In southern hemisphere zeolite, such as found in Australia, which were formed with fresh water, thus the calcium uptake on formation.
Zeolite is an effective ammonia filter, but must be used with some care, especially with delicate tropical corals which are sensitive to water chemistry and temperature.
Space hardware testing
zeolite 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 is often made of zeolite or diatomite.
External links
Database of Zeolite StructuresThe Synthesis Commission of the International Zeolite Association
Molecular Sieves Infomation
Link: http://www.xmzeolite.com/Zeolites_Molecular_Sieve_Powder_products.html
Zeolites (Greek, zein, "to boil"; lithos, "a stone") are aluminosilicate minerals and have a microporous structure (pores smaller than 2 nm).
The term zeolite was originally coined in the 18th century by Swedish mineralogist Axel Fredrik Cronstedt, who observed that upon rapidly heating a natural mineral, the stones began to dance about. Using the Greek words which mean "stone that boils," he called this material zeolite. The stones "boiled" because the water adsorbed inside the zeolite's pores was driven off by heating.
More than 175 unique zeolite frameworks have been identified, and 48 naturally occurring zeolites are known. zeolites have a porous structure that can accommodate a wide variety of cations, such as Na+, K+, Ca2+, Mg2+ and others. These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are: analcime, chabazite, heulandite, natrolite, phillipsite, and stilbite. An example mineral formula is: Na2Al2Si3O10-2H2O, the formula for natrolite.
Natural zeolites form where volcanic rocks and ash layers react with alkaline groundwater. zeolites also crystallize in post-depositional environments over periods ranging from thousands to millions of years in shallow marine basins. Naturally occurring zeolites are rarely pure and are contaminated to varying degrees by other minerals, metals, quartz, or other zeolites. For this reason, naturally occurring zeolites are excluded from many important commercial applications where uniformity and purity are essential.
zeolites are the aluminosilicate members of the family of microporous solids known as "molecular sieves." The term molecular sieve refers to a particular property of these materials, i.e. the ability to selectively sort molecules based primarily on a size exclusion process. This is due to a very regular pore structure of molecular dimensions. The maximum size of the molecular or ionic species that can enter the pores of a zeolite is controlled by the dimensions of the channels. These are conventionally defined by the ring size of the aperture, where, for example, the term "8-ring" refers to a closed loop that is built from 8 tetrahedrally coordinated silicon (or aluminum) atoms and 8 oxygen atoms. These rings are not always perfectly symmetrical due to a variety of effects, including strain induced by the bonding between units that are needed to produce the overall structure, or coordination of some of the oxygen atoms of the rings to cations within the structure. Therefore, the pores in many zeolites are not cylindrical.
Sources
Conventional open pit mining techniques in Arkansas are used to mine natural zeolites. The overburden is removed to allow access to the ore. The ore may be blasted or stripped for processing by using tractors equipped with ripper blades and front-end loaders. In processing, the ore is crushed, dried, and milled. The milled ore may be air-classified as to particle size and shipped in bags or bulk. The crushed product may be screened to remove fine material when a granular product is required, and some pelletized products are produced from fine material. Producers also may modify the properties of the zeolite or blend their zeolite products with other materials before sale to enhance their performance.
Currently, the world’s annual production of natural zeolite is about 4 million tons. Of this quantity, 2.6 million tons are shipped to Chinese markets to be used in the concrete industry. Eastern Europe, Western Europe, Australia, and Asia are world leaders in supplying the world’s demand for natural zeolite. By comparison, only 57,400 metric tons (source: U.S. Geological Survey, 2004) of zeolite (only 1% of the world’s current production) is produced in North America; only recently has North America realized the potential for current and future markets.
There are several types of synthetic zeolites that form by a process of slow crystallization of a silica-alumina gel in the presence of alkalis and organic templates. One of the important processes used to carry out zeolite synthesis is sol-gel processing. The product properties depend on reaction mixture composition, pH of the system, operating temperature, pre-reaction 'seeding' time, reaction time as well as the templates used. In sol-gel process, other elements (metals, metal oxides) can be easily incorporated. The silicalite sol formed by the hydrothermal method is very stable. Also the ease of scaling up this process makes it a favorite route for zeolite synthesis.
Synthetic zeolites hold some key advantages over their natural analogs. The synthetics can, of course, be manufactured in a uniform, phase-pure state. It is also possible to manufacture desirable zeolite structures which do not appear in nature. zeolite A is a well-known example. Since the principal raw materials used to manufacture zeolites are silica and alumina, which are among the most abundant mineral components on earth, the potential to supply zeolites is virtually unlimited. Finally, zeolite manufacturing processes engineered by man require significantly less time than the 50 to 50,000 years prescribed by nature. Disadvantages include the inability to create crystals with dimensions of a comparable size to their natural counterparts.
Uses
Commercial and Domestic
zeolites are widely used as ion-exchange beds in domestic and commercial water purification, softening, and other applications. In chemistry, 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 have the potential of providing precise 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 this 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 isomerisation, alkylation, and cracking. The specific activation modality of most zeolitic catalysts used in petrochemical applications involves quantum-chemical Lewis acid site reactions. Catalytic cracking uses a furnace and reactor. First crude oil distillation 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 this 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 have uses in advanced reprocessing methods, where their micro-porous ability to capture some ions while allowing others to pass freely allow many fission products to be efficiently removed from nuclear waste and permanently trapped. Equally important are the mineral properties of zeolites. Their alumino-silicate construction is extremely durable and resistant to radiation even in porous form. Additionally, once they are loaded with trapped fission 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. This is a waste form factor that greatly reduces its hazard compared to conventional reprocessing systems.
Agriculture
In agriculture, clinoptilolite (a naturally occurring zeolite) is 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. zeolite 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. This property can prevent root rot and moderate drought cycles.
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 is 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, leaving highly purified oxygen and up to 5% argon. QuikClot® brand hemostatic agent, which continues to be used successfully to save lives by stopping severe bleeding, contains a calcium loaded form of zeolite.
Heating and refrigeration
zeolite 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 is exploited. This hygroscopic property coupled with an inherent exothermic (heat producing) reaction when transitioning from a dehydrated to a hydrated form, make natural zeolite useful in harvesting waste heat and solar heat energy.
Detergents
The largest single use for zeolite is the global laundry detergent market. This amounted to 1.44 million metric tons per year of anhydrous zeolite A in 1992.
Construction
Synthetic zeolite is also being used as an additive in the production process of warm mix asphalt concrete. The development of this 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 paving 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, have been collected as gemstones from a series of lava flows along Lake Superior in Minnesota and to a lesser degree in Michigan, U.S.A.. Thomsonite nodules from these areas have eroded from basalt lava flows and are collected on beaches and by scuba divers in Lake Superior.
These thomsonite nodules have concentric rings in combinations of colors, black, white, orange, pink, red and many shades of green. Some nodules have copper as inclusions and rarely will be found with copper "eyes". When polished by a lapidary the thomsonites sometimes display chatoyancy
Aquarium keeping
zeolite are marketed by pet stores for use as a filter additive in aquariums. In aquariums, zeolite can be used to absorb ammonia and other nitrogenous compounds. However, due to the high affinity of some zeolite for calcium, they may be less effective in hard water and may deplete calcium. Zeolite filtration is used in some marine aquaria to keep nutrient concentrations low for the benefit of corals adapted to nutrient-depleted waters.
Where and how the zeolite was formed is an important consideration for aquariums. Northern hemisphere natural zeolite were formed when molten lava came in contact with sea water, thereby 'loading' the zeolite with Na (sodium) sacrificial ions. These sodium ions will speciate with other ions in solution, thus the takeup of nitrogen in ammonia, with the release of the sodium. In southern hemisphere zeolite, such as found in Australia, which were formed with fresh water, thus the calcium uptake on formation.
Zeolite is an effective ammonia filter, but must be used with some care, especially with delicate tropical corals which are sensitive to water chemistry and temperature.
Space hardware testing
zeolite 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 is often made of zeolite or diatomite.
External links
Database of Zeolite StructuresThe Synthesis Commission of the International Zeolite Association
Molecular Sieves Infomation
Link: http://www.xmzeolite.com/Zeolites_Molecular_Sieve_Powder_products.html
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