Benzalkonium chloride, also known as alkyldimethylbenzylammonium chloride and ADBAC, is a mixture of alkylbenzyldimethylammonium chlorides of various even-numbered[2] alkyl chain lengths. This product is a nitrogenous cationic surface-acting agent belonging to the quaternary ammonium group. It has three main categories of use; as a biocide, a cationic surfactant and phase transfer agent in the chemical industry.
Contents
1 Properties
2 Availability
3 Applications
4 Biological activity
5 Safety
6 References
7 Further reading
8 External links
9 References
Properties
Benzalkonium chloride is readily soluble in ethanol and acetone. Although dissolution in water is slow, aqueous solutions are easier to handle and are preferred. Solutions should be neutral to slightly alkaline, with colour ranging from clear to a pale yellow. Solutions foam profusely when shaken, have a bitter taste and a faint almond-like odour which is only detectable in concentrated solutions.
Availability
Standard concentrates are manufactured as 50% and 80% w/w solutions, and sold under trade names such as BC50, BC80, BAC50, BAC80, etc. The 50% solution is purely aqueous, while more concentrated solutions require incorporation of rheology modifiers (alcohols, polyethylene glycols, etc.) to prevent increases in viscosity or gel formation under low temperature conditions.
Applications
Applications are extremely wide ranging,[3] from disinfectant formulations to microbial corrosion inhibition in the oilfield sector. It has been considered one of the safest synthetic biocides known and has a long history of efficacious use. It is currently used in human pharmaceuticals such as leave-on skin antiseptics, hygienic towelettes, and wet wipes. Ethanol-free benzalkonium solutions are often used for skin disinfection prior to withdrawing blood for blood alcohol content tests. Its use as a preservative in cosmetics such as eye and nasal drops attests to its general safety; however, there have been reports of allergy associated with continuous, long-term use in sensitive users, especially on mucous membranes.
Biological activity
The greatest biocidal activity is associated with the C12-C14 alkyl derivatives. The mechanism of bactericidal/microbicidal action is thought to be due to disruption of intermolecular interactions. This can cause dissociation of cellular membrane bilayers, which compromises cellular permeability controls and induces leakage of cellular contents. Other biomolecular complexes within the bacterial cell can also undergo dissociation. Enzymes, which finely control a plethora of respiratory and metabolic cellular activities, are particularly susceptible to deactivation. Critical intermolecular interactions and tertiary structures in such highly specific biochemical systems can be readily disrupted by cationic surfactants.
Benzalkonium chloride solutions are rapidly acting biocidal agents with a moderately long duration of action. They are active against bacteria and some viruses, fungi, and protozoa. Bacterial spores are considered to be resistant. Solutions are bacteriostatic or bactericidal according to their concentration. Gram-positive bacteria are generally more susceptible than Gram-negative. Activity is not greatly affected by pH, but increases substantially at higher temperatures and prolonged exposure times.
Newer formulations using benzalkonium blended with various quaternary ammonium derivatives can be used to extend the biocidal spectrum and enhance the efficacy of benzalkonium based disinfection products. This technique has been used to improve virucidal activity of quaternary ammonium-based formulations to healthcare infection hazards such as hepatitis, HIV, etc. Quaternary ammonium formulations are now the disinfectants of choice for hospitals. This is on account of user and patient safety even on contact with treated surfaces and the absence of harmful fumes. Benzalkonium solutions for hospital use tend to be neutral to alkaline, non-corrosive on metal surfaces, non-staining and safe to use on all washable surfaces.
The use of appropriate supporting excipients can also greatly improve efficacy and detergency, and prevent deactivation under use conditions. Formulation requires great care as benzalkonium solutions can be readily inactivated in the presence of organic and inorganic contamination. Solutions are incompatible with soaps, and must not be mixed with anionic surfactants. Hard water salts can also reduce biocidal activity. As with any disinfectant, it is recommended that surfaces are free from visible dirt and interfering materials for maximal disinfection performance by quaternary ammonium products.
Although hazardous levels are not likely to be reached under normal use conditions, it is important to remember that benzalkonium and other detergents can pose a hazard to marine organisms. Quaternary ammonium disinfectants are effective at very low ppm levels, so it is important to avoid excess in use. Responsible care ensures that the fragile marine ecosystems that sustain us are not disrupted.
Safety
Benzalkonium chloride is an allergen[4][5][6][7][8][9][10] and several studies have cast doubt on its reputation for safety.[11][12]
Some products have been reformulated in light of this research, but it is still widely used in eyewashes, hand and face washes, mouthwashes, spermicidal creams, and in various other cleaners, sanitizers, and disinfectants. Manufacturers of over-the-counter artificial tears and eye washes became concerned about chemical sensitivity from long-term daily use and have in some products substituted EDTA as a preservative. Some have added "for sensitive eyes" to labeling. There has also been concern that long-term use of benzalkonium as a preservative in nose sprays may cause swelling of mucosa and lead to rhinitis medicamentosa. Some manufacturers have put 3-day limits on safe use of such nose sprays.
A disinfectant containing benzalkonium chloride and the related compound didecyl-dimethyl ammonium chloride (DDAC) has been identified as the most probable cause of birth defects and fertility problems in caged mice.[13]
References
1.^ a b c Record of Quaternary ammonium compounds, benzyl-C8–18-alkyldimethyl, chlorides in the European chemical Substances Information System ESIS
2.^ US EPA: Reregistration Eligibility Decision for Alkyl Dimethyl Benzyl Ammonium Chloride (ADBAC)
3.^ quatchem.co.uk
4.^ Park HJ, Kang HA, Lee JY, Kim HO (2000). "Allergic contact dermatitis from benzalkonium chloride in an antifungal solution". Contact Derm. 42 (5): 306–7. PMID 10789868.
5.^ Liu H, Routley I, Teichmann KD (2001). "Toxic endothelial cell destruction from intraocular benzalkonium chloride". J Cataract Refract Surg 27 (11): 1746–50. doi:10.1016/S0886-3350(01)01067-7. PMID 11709246.
6.^ Chiambaretta F, Pouliquen P, Rigal D (1997). "[Allergy and preservatives. Apropos of 3 cases of allergy to benzalkonium chloride]" (in French). J Fr Ophtalmol 20 (1): 8–16. PMID 9099278.
7.^ Wong DA, Watson AB (2001). "Allergic contact dermatitis due to benzalkonium chloride in plaster of Paris". Australas. J. Dermatol. 42 (1): 33–5. doi:10.1046/j.1440-0960.2001.00469.x. PMID 11233718.
8.^ Kanerva L, Jolanki R, Estlander T (2000). "Occupational allergic contact dermatitis from benzalkonium chloride". Contact Derm. 42 (6): 357–8. PMID 10871106.
9.^ Oiso N, Fukai K, Ishii M (2005). "Irritant contact dermatitis from benzalkonium chloride in shampoo". Contact Derm. 52 (1): 54. doi:10.1111/j.0105-1873.2005.0483j.x. PMID 15701139.
MST
Link http://en.wikipedia.org/wiki/Benzalkonium_chloride
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Sunday, 19 October 2008
Sunday, 21 September 2008
OXYGEN CLEANERS, Sodium Percarbonate
The Benefits Of Oxygen Cleaners
By CP Editorial Staff
Email the CP editors
________________________________________
For years, building service contractors have relied on traditional butyl-based chemicals. While effective, these products could also damage surfaces and be detrimental to worker health when used improperly. Some BSCs are looking to alternative cleaners such as oxygen-based products to provide a safer work environment.
One type of oxygen cleaner is an oxygen-based bleach cleaner that uses sodium percarbonate as its main ingredient. However, the more common oxygen cleaners in today’s market are hydrogen peroxide-based.
Hydrogen peroxide molecules are comprised of two atoms of hydrogen and two atoms of oxygen. Surfactants and orange oil are added to the hydrogen peroxide to help it penetrate the surface and reach the embedded soil. When the cleaner comes into contact with the soil, the hydrogen peroxide releases oxygen to boost the cleaning power of the surfactants. The only by-products of the reaction between the cleaner and the stain are oxygen and water. Little to no residue, which can lead to re-soiling, is left on the surface.
Hydrogen-peroxide cleaners are designed to remove proteins and other stains and soil of organic nature. They work well on dried tannin stains, such as coffee, red wine and cola. Diluting the product to either a heavy-duty cleaner or light-duty cleaner should address the majority of general cleaning needs in a facility. The cleaners are effective on both porous and non-porous surfaces including marble, stone, wood laminate, white boards, desktops, tile, grout, plexi-glass, glass, carpet, leather and porcelain.
Oxygen cleaners deodorize the surface in addition to cleaning it because the hydrogen peroxide actually destroys the organic source of odors.
However, it is important to note that oxygen-based products will not clean everything. They do not work on mineral or petroleum-based soils and stains such as oil and gum.
Since oxygen cleaners can be used on a variety of surfaces and for a number of stains, BSCs don’t need to stock a multitude of products and can reduce the possibility for error. If a chemical is misused on a surface, or even used correctly on the wrong surface, it can cause serious damage. Fewer products will create less confusion for employees.
Oxygen cleaners are also safer for employees and the environment. They contain low levels of volatile organic compounds (VOCs) and are non-irritants to skin. If a worker accidentally spills or sprays the product on himself, it will not cause serious injuries.
Read More..
By CP Editorial Staff
Email the CP editors
________________________________________
For years, building service contractors have relied on traditional butyl-based chemicals. While effective, these products could also damage surfaces and be detrimental to worker health when used improperly. Some BSCs are looking to alternative cleaners such as oxygen-based products to provide a safer work environment.
One type of oxygen cleaner is an oxygen-based bleach cleaner that uses sodium percarbonate as its main ingredient. However, the more common oxygen cleaners in today’s market are hydrogen peroxide-based.
Hydrogen peroxide molecules are comprised of two atoms of hydrogen and two atoms of oxygen. Surfactants and orange oil are added to the hydrogen peroxide to help it penetrate the surface and reach the embedded soil. When the cleaner comes into contact with the soil, the hydrogen peroxide releases oxygen to boost the cleaning power of the surfactants. The only by-products of the reaction between the cleaner and the stain are oxygen and water. Little to no residue, which can lead to re-soiling, is left on the surface.
Hydrogen-peroxide cleaners are designed to remove proteins and other stains and soil of organic nature. They work well on dried tannin stains, such as coffee, red wine and cola. Diluting the product to either a heavy-duty cleaner or light-duty cleaner should address the majority of general cleaning needs in a facility. The cleaners are effective on both porous and non-porous surfaces including marble, stone, wood laminate, white boards, desktops, tile, grout, plexi-glass, glass, carpet, leather and porcelain.
Oxygen cleaners deodorize the surface in addition to cleaning it because the hydrogen peroxide actually destroys the organic source of odors.
However, it is important to note that oxygen-based products will not clean everything. They do not work on mineral or petroleum-based soils and stains such as oil and gum.
Since oxygen cleaners can be used on a variety of surfaces and for a number of stains, BSCs don’t need to stock a multitude of products and can reduce the possibility for error. If a chemical is misused on a surface, or even used correctly on the wrong surface, it can cause serious damage. Fewer products will create less confusion for employees.
Oxygen cleaners are also safer for employees and the environment. They contain low levels of volatile organic compounds (VOCs) and are non-irritants to skin. If a worker accidentally spills or sprays the product on himself, it will not cause serious injuries.
Read More..
Tuesday, 26 August 2008
BENTONITE
SODIUM BENTONITE
Sodium bentonite expands when wet, possibly absorbing several times its dry mass in water. It is mostly used in drilling mud for oil and gas wells and for geotechnical and environmental investigations.
The property of swelling also makes sodium bentonite useful as a sealant, especially for the sealing of subsurface disposal systems for spent nuclear fuel [1] [2] and for quarantining metal pollutants of groundwater. Similar uses include making slurry walls, waterproofing of below-grade walls and forming other impermeable barriers (e.g. to plug old wells or as a liner in the base of landfills to prevent migration of leachate into the soil).
CALCIUM BENTONITE
The non-swelling calcium bentonite is sold within the alternative health market for its purported cleansing properties. It is usually combined with water and ingested, often as part of a detox diet, [3] in a practice known as geophagy. It is claimed that the microscopic structure of the bentonite draws impurities into it from the digestive system, which are then excreted along with the bentonite; no scientific studies exist to support these claims. There are claims that native tribes in South America, Africa and Australia have long used bentonite clay for this purpose. [4]
Calcium bentonite may be converted to sodium bentonite and exhibit sodium bentonite's properties by a process known as "ion exchange". Commonly this means adding 5-10% of sodium carbonate to wet bentonite, mixing well, and allowing time for the ion exchange to take place.
Pascalite is another commercial name for the calcium bentonite clay.
USES for BOTH TYPES
Much of bentonite's usefulness in the drilling and geotechnical engineering industry comes from its unique rheological properties. Relatively small quantities of bentonite suspended in water form a viscous, shear thinning material. Most often, bentonite suspensions are also thixotropic, although rare cases of rheopectic behavior have also been reported. At high enough concentrations (~60 grams of bentonite per litre of suspension), bentonite suspensions begin to take on the characteristics of a gel (a fluid with a minimum yield strength required to make it move). For these reasons it is a common component of drilling mud used to curtail drilling fluid invasion by its propensity for aiding in the formation of mud cake.
Bentonite can be used in cement, adhesives, ceramic bodies, cosmetics and cat litter. Fuller's earth, an ancient dry cleaning substance, is finely ground bentonite, typically used for purifying transformer oil. Bentonite, in small percentages, is used as an ingredient in commercially designed clay bodies and ceramic glazes. Bentonite clay is also used in pyrotechnics to make end plugs and rocket nozzles, and can also be used as a therapeutic face pack for the treatment of acne/oily skin.
The ionic surface of bentonite has a useful property in making a sticky coating on sand grains. When a small proportion of finely ground bentonite clay is added to hard sand and wetted, the clay binds the sand particles into a moldable aggregate known as green sand used for making molds in sand casting. Some river deltas naturally deposit just such a blend of such clay silt and sand, creating a natural source of excellent molding sand that was critical to ancient metalworking technology. Modern chemical processes to modify the ionic surface of bentonite greatly intensify this stickiness, resulting in remarkably dough-like yet strong casting sand mixes that stand up to molten metal temperatures.
The same effluvial deposition of bentonite clay onto beaches accounts for the variety of plasticity of sand from place to place for building sand castles. Beach sand consisting of only silica and shell grains does not mold well compared to grains coated with bentonite clay. This is why some beaches are so much better for building sand castles than others.
The self-stickiness of bentonite allows high-pressure ramming or pressing of the clay in molds to produce hard, refractory shapes, such as model rocket nozzles. Indeed, to test whether a particular brand of cat litter is bentonite, simply ram a sample with a hammer into a sturdy tube with a close-fitting rod; bentonite will form a very hard, consolidated plug that is not easily crumbled.
Bentonite also has the interesting property of adsorbing relatively large amounts of protein molecules from aqueous solutions. It is therefore uniquely useful in the process of winemaking, where it is used to remove excessive amounts of protein from white wines. Were it not for this use of bentonite, many or most white wines would precipitate undesirable flocculent clouds or hazes upon exposure to warmer temperatures, as these proteins denature. It also has the incidental use of inducing more rapid clarification of both red and white wines.
History and natural occurrence
In 2005, U.S. was the top producer of bentonite with almost one-third world share followed by China and Greece, reports the British Geological Survey.
The absorbent clay was given the name bentonite by an American geologist sometime after its discovery in about 1890 — after the Benton Formation (a geological stratum, at one time Fort Benton) in Montana's Rock Creek area. Other modern discoveries include montmorillonite discovered in 1847 in Montmorillon in the Vienne prefecture of France, in Poitou-Charentes, South of the Loire Valley.
Most high grade commercial sodium bentonite mined in the United States comes from the area between the Black Hills of South Dakota and the Big Horn Basin of Wyoming. Sodium bentonite is also mined in the southwestern United States, in Greece and in other regions of the world. Calcium bentonite is mined in the Great Plains, Central Mountains and south eastern regions of the United States. Supposedly the world's largest current reserve of bentonite is Chongzuo in China's Guangxi province.[citation needed]
It should be noted that in some countries like the UK, calcium bentonite is known as fuller's earth, a term which is also used to refer attapulgite, a mineralogically distinct clay mineral but exhibiting similar properties.
Early Americans found bentonite vital to their lives. Pioneers found moistened bentonite to be an ideal lubricant for squeaky wagon wheels. The mixture was also used as a sealant for log cabin roofing. The Indians found bentonite useful as a soap.
Small amounts of Wyoming bentonite were first commercially mined and developed in the Rock River area during the 1880s. Newer, more substantial deposits were discovered in other parts of Wyoming during the 1920s and the first processing plant in Wyoming was built during this period. Since that time many other processing plants have been built for the purpose of processing Wyoming sodium bentonite. Wyoming's Bentonite industry produced over 4.0 million tons of bentonite in 1999, with 644 mine and mill employees, and 240 contractor employees.
Wyoming bentonite is composed essentially of montmorillonite clay, also known as hydrous silicate of alumina. In more simplistic terms, the structure of bentonite is much like a sandwiched deck of cards. When placed in water, these cards or clay platelets shift apart. Bentonite attracts water to its negative face and magnetically holds the water in place. because of this unique characteristic, Wyoming bentonite is capable of absorbing 7 to 10 times its own weight in water, and swelling up to 18 times its dry volume.
Exploration for new bentonite beds is normally accomplished with auger bit drilling. Once the auger drill stem reaches the soft bentonite it sinks very rapidly, which indicates to the driller that bentonite has been found. The auger flights are then withdrawn and the "sticky" bentonite is sampled from the flights for quality analysis. Bentonite is mined by surface "open pit" methods. Various types of heavy equipment including bull dozers and rubber-tired scrapers are used to remove the shale rock overlying the bentonite.
Topsoil, as well as the underlying material, is carefully removed and stockpiled. These "overburden" materials as they are called will be placed back and reseeded once the bentonite has been removed. The bentonite which is exposed during this process can be as little as 1 1/2 feet or as much as 10 feet thick. This is the material which is mined and processed.
Many bentonite manufactures prefer to "field dry" the exposed bentonite prior to hauling it to the processing plants. This is accomplished by plowing and discing while taking advantage of the low humidity and sunny days to dry the bentonite prior to its removal. The moisture level prior to "field drying" can exceed 30%. This process will normally extract 15 to 20% of the moisture from the clay prior to hauling.
Upon arrival at the processing plants, the bentonite is placed into designated stockpiles and carried into the plant with front-end loaders. The bentonite is then dried in a long cylinder called a rotary dryer where approximately 10 to 15% of the moisture is removed. Natural gas or coal are used primarily as fuels for drying. The finished product has moisture content of 7 to 10%.
Once delivered from the rotary dryer, the bentonite is processed into either a fine powder or granulated into a small particle or flake. Packaging of the product is the last process to be undertaken. Granular bentonite is a major constituent of "scoopable" cat litter. Bentonite can be packaged in 50 lb., 100 lb. or up to 4,000 lb. super sacks. After the packaging process takes place, the bentonite is shipped either by truck or rail to the consumer. Another form of packaging is to ship direct in bulk pneumatic trucks or rail cars to the consumer.
WELL DRILLING
Drilling mud, or drilling gel, is a major component in the well drilling process. Drilling mud is crucial in the extraction of drill cuttings during the drilling process. Bentonite, when mixed with water, forms a fluid (or slurry) that is pumped through the drill stem, and out through the drill bit. The bentonite extracts the drill cuttings from around the bit, which are then floated to the surface. The drilling mud, or gel, also serves to cool and lubricate the drill bit as well as seal the drill hole against seepage and to prevent wall cave-ins
TACONITE PELLETIZING
Taconite, a low grade iron ore, has been developed as an economic source for iron. During processing, the taconite is ground into a very fine powder. The ground taconite is then mixed with small amounts of bentonite which serves as a binder to the taconite. This mixture is processed into balls or pellets. The process is finished when these pellets are sintered in rotary kilns that give the pellets a hard surface. The taconite pellets are easy to handle at this point and can be loaded into various containers for shipment to steel mills.
METAL CASTING
Bentonite serves as an economical bonding material in the molding processes associated with the metal casting industry. Bentonite, when mixed with foundry molding sands, forms a pliable bond with the sand granules. Impressions are formed into the face of the bentonite/sand mixtures. Molten metal is pored into the impressions at temperatures exceeding 2,800 F. The unique bonding characteristics of bentonite insures the durability of the mold during these high temperatures. Once the process is complete, the bentonite/sand mold can then be broken away from the casting face and reused.
CAT LITTER
In recent years, bentonite has become a major component in the manufacturing of cat litter. Because of the unique water absorption, swelling, and odor controlling characteristics of bentonite, it is ideal for use in "clumping" types of cat litters. Clumping cat litter has become widely accepted as an economical alternative to conventional non-clumping type cat litters. Because bentonite forms clumps when wet, the clumps can easily be removed and disposed of. The remainder of the unused material stays intact and can continue to be used. clumping cat box litters will last longer with less frequency of changing.
ANIMAL/POUTRY FEEDS
For many years bentonite has been used as a binder in the feed pelletizing industry. Small amounts of bentonite can be added to feed products to insure tougher, more durable pellets. By absorbing excess moisture and oils, bentonite aids in the free movement of pellets, preventing lumping and caking. Research has been conducted which indicates that bentonite has additional benefits for both animals and poultry. The bentonite used in the feed slows the digestive system and enables the animal or fowl to better utilize the feed nutrients. Other studies have shown bentonite as a useful ingredient in the control of certain toxins which affect animals and fowl.
OTHER APPLICATIONS
Bentonite has also proved helpful in sealing freshwater ponds, irrigation ditches, reservoirs, sewage and industrial water lagoons, and in grouting permeable ground. In addition, it has been used in detergents, fungicides, sprays, cleansers, polishes, ceramic, paper, cosmetics and applications where its unique bonding, suspending or gellant properties are required.
Normal Drilling Mud Properties
ELEMENT
PRECENTAGE
SiO2
66.9%
Al2O3
16.3%
H2O (Crystal)
6.0%
Fe2O3
3.3%
Na2O
2.6%
CaO
1.8%
MgO
1.5%
K2O
0.48%
TiO2
0.12%
Source: Black Hills Bentonite, LLC.
Bentonite Mining Operations by Area
Bentonite
What is Bentonite?
The term Bentonite was first used for a clay found in about 1890 in upper cretaceous tuff near Fort Benton, Wyoming. The main constituent, which is the determinant factor in the clay's properties, is the clay mineral montmorillonite. This in turn, derives its name from a deposit at Montmorillon, in Southern France.
Bentonite is a clay generated frequently from the alteration of volcanic ash, consisting predominantly of smectite minerals, usually montmorillonite. Other smectite group minerals include hectorite, saponite, beidelite and nontronite. Smectites are clay minerals, i.e. they consist of individual crystallites the majority of which are <2µm in largest dimension. Smectite crystallites themselves are three-layer clay minerals. They consist of two tetrahedral layers and one octahedral layer. In montmorillonite tetrahedral layers consisting of [SiO4] - tetrahedrons enclose the [M(O5,OH)]-octahedron layer (M = and mainly Al, Mg, but Fe is also often found). The silicate layers have a slight negative charge that is compensated by exchangeable ions in the intercrystallite region. The charge is so weak that the cations (in natural form, predominantly Ca2+, Mg2+ or Na+ ions) can be adsorbed in this region with their hydrate shell. The extent of hydration produces intercrystalline swelling. Depending on the nature of their genesis, bentonites contain a variety of accessory minerals in addition to montmorillonite. These minerals may include quartz, feldspar, calcite and gypsum. The presence of these minerals can impact the industrial value of a deposit, reducing or increasing its value depending on the application. Bentonite presents strong colloidal properties and its volume increases several times when coming into contact with water, creating a gelatinous and viscous fluid. The special properties of bentonite (hydration, swelling, water absorption, viscosity, thixotropy) make it a valuable material for a wide range of uses and applications.
Bentonite deposits are normally exploited by quarrying. Extracted bentonite is distinctly solid, even with a moisture content of approximately 30%. The material is initially crushed and, if necessary, activated with the addition of soda ash (Na2CO3). Bentonite is subsequently dried (air and/or forced drying) to reach a moisture content of approximately 15%. According to the final application, bentonite is either sieved (granular form) or milled (into powder and super fine powder form). For special applications, bentonite is purified by removing the associated gangue minerals, or treated with acids to produce acid-activated bentonite (bleaching earths), or treated with organics to produce organoclays.
Foundry: Bentonite is used as a bonding material in the preparation of molding sand for the production of iron, steel and non-ferrous casting. The unique properties of bentonite yield green sand moulds with good flowability, compactability and thermal stability for the production of high quality castings.
Cat Litter: Bentonite is used for cat litter, due to its advantage of absorbing refuse by forming clumps (which can be easily removed) leaving the remaining product intact for further use.
Pelletizing: Bentonite is used as a binding agent in the production of iron ore pellets. Through this process, iron ore fines are converted into spherical pellets, suitable as feed material in blast furnaces for pig iron production, or in the production of direct reduction iron (DRI).
Construction and Civil Engineering: Bentonite in civil engineering applications is used traditionally as a thixotropic, support and lubricant agent in diaphragm walls and foundations, in tunnelling, in horizontal directional drilling and pipe jacking. Bentonite, due to its viscosity and plasticity, also is used in Portland cement and mortars.
Environmental Markets: Bentonite's adsorption/absorption properties are very useful for wastewater purification. Common environmental directives recommend low permeability soils, which naturally should contain bentonite, as a sealing material in the construction and rehabilitation of landfills to ensure the protection of groundwater from the pollutants. Bentonite is the active protective layer of geosynthetic clay liners.
Drilling: Another conventional use of bentonite is as a mud constituent for oil and water well drilling. Its roles are mainly to seal the borehole walls, to remove drill cuttings and to lubricate the cutting head.
Oils/Food Markets: Bentonite is utilized in the removal of impurities in oils where its adsorptive properties are crucial in the processing of edible oils and fats (Soya/palm/canola oil). In drinks such as beer, wine and mineral water, and in products like sugar or honey, bentonite is used as a clarification agent.
Agriculture: Bentonite is used as an animal feed supplement, as a pelletizing aid in the production of animal feed pellets, as well as a flowability aid for unconsolidated feed ingredients such as soy meal. It also is used as an ion exchanger for improvement and conditioning of the soil. When thermally treated, it can be used as a porous ceramic carrier for various herbicides and pesticides.
Pharmaceuticals, Cosmetics and Medical Markets: Bentonite is used as filler in pharmaceuticals, and due to its absorption/adsorption functions, it allows paste formation. Such applications include industrial protective creams, calamine lotion, wet compresses, and antiirritants for eczema. In medicine, bentonite is used as an antidote in heavy metal poisoning. Personal care products such as mud packs, sunburn paint, baby and facepowders, and face creams may all contain bentonite.
Detergents: Laundry detergents and liquid hand cleansers/soaps rely on the inclusion of bentonite, in order to remove the impurities in solvents and to soften the fabrics.
Paints, Dyes and Polishes: Due to its thixotropic properties, bentonite and organoclays function as a thickening and/or suspension agent in varnishes, and in water and solvent paints. Its adsorption properties are appreciated for the finishing of indigo dying cloth, and in dyes (lacquers for paints & wallpapers).
Paper: Bentonite is crucial to paper making, where it is used in pitch control, i.e. absorption of wood resins that tend to obstruct the machines and to improve the efficiency of conversion of pulp into paper as well as to improve the quality of the paper. Bentonite also offers useful de-inking properties for paper recycling. In addition, acid-activated bentonite is used as the active component in the manufacture of carbonless copy paper.
Catalyst: Chemically-modified clay catalysts find application in a diverse range of duties where acid catalysis is a key mechanism. Most particularly, they are employed in the alkylation processes to produce fuel additives.
Succes for You All,
Michael S. Thang
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Sodium bentonite expands when wet, possibly absorbing several times its dry mass in water. It is mostly used in drilling mud for oil and gas wells and for geotechnical and environmental investigations.
The property of swelling also makes sodium bentonite useful as a sealant, especially for the sealing of subsurface disposal systems for spent nuclear fuel [1] [2] and for quarantining metal pollutants of groundwater. Similar uses include making slurry walls, waterproofing of below-grade walls and forming other impermeable barriers (e.g. to plug old wells or as a liner in the base of landfills to prevent migration of leachate into the soil).
CALCIUM BENTONITE
The non-swelling calcium bentonite is sold within the alternative health market for its purported cleansing properties. It is usually combined with water and ingested, often as part of a detox diet, [3] in a practice known as geophagy. It is claimed that the microscopic structure of the bentonite draws impurities into it from the digestive system, which are then excreted along with the bentonite; no scientific studies exist to support these claims. There are claims that native tribes in South America, Africa and Australia have long used bentonite clay for this purpose. [4]
Calcium bentonite may be converted to sodium bentonite and exhibit sodium bentonite's properties by a process known as "ion exchange". Commonly this means adding 5-10% of sodium carbonate to wet bentonite, mixing well, and allowing time for the ion exchange to take place.
Pascalite is another commercial name for the calcium bentonite clay.
USES for BOTH TYPES
Much of bentonite's usefulness in the drilling and geotechnical engineering industry comes from its unique rheological properties. Relatively small quantities of bentonite suspended in water form a viscous, shear thinning material. Most often, bentonite suspensions are also thixotropic, although rare cases of rheopectic behavior have also been reported. At high enough concentrations (~60 grams of bentonite per litre of suspension), bentonite suspensions begin to take on the characteristics of a gel (a fluid with a minimum yield strength required to make it move). For these reasons it is a common component of drilling mud used to curtail drilling fluid invasion by its propensity for aiding in the formation of mud cake.
Bentonite can be used in cement, adhesives, ceramic bodies, cosmetics and cat litter. Fuller's earth, an ancient dry cleaning substance, is finely ground bentonite, typically used for purifying transformer oil. Bentonite, in small percentages, is used as an ingredient in commercially designed clay bodies and ceramic glazes. Bentonite clay is also used in pyrotechnics to make end plugs and rocket nozzles, and can also be used as a therapeutic face pack for the treatment of acne/oily skin.
The ionic surface of bentonite has a useful property in making a sticky coating on sand grains. When a small proportion of finely ground bentonite clay is added to hard sand and wetted, the clay binds the sand particles into a moldable aggregate known as green sand used for making molds in sand casting. Some river deltas naturally deposit just such a blend of such clay silt and sand, creating a natural source of excellent molding sand that was critical to ancient metalworking technology. Modern chemical processes to modify the ionic surface of bentonite greatly intensify this stickiness, resulting in remarkably dough-like yet strong casting sand mixes that stand up to molten metal temperatures.
The same effluvial deposition of bentonite clay onto beaches accounts for the variety of plasticity of sand from place to place for building sand castles. Beach sand consisting of only silica and shell grains does not mold well compared to grains coated with bentonite clay. This is why some beaches are so much better for building sand castles than others.
The self-stickiness of bentonite allows high-pressure ramming or pressing of the clay in molds to produce hard, refractory shapes, such as model rocket nozzles. Indeed, to test whether a particular brand of cat litter is bentonite, simply ram a sample with a hammer into a sturdy tube with a close-fitting rod; bentonite will form a very hard, consolidated plug that is not easily crumbled.
Bentonite also has the interesting property of adsorbing relatively large amounts of protein molecules from aqueous solutions. It is therefore uniquely useful in the process of winemaking, where it is used to remove excessive amounts of protein from white wines. Were it not for this use of bentonite, many or most white wines would precipitate undesirable flocculent clouds or hazes upon exposure to warmer temperatures, as these proteins denature. It also has the incidental use of inducing more rapid clarification of both red and white wines.
History and natural occurrence
In 2005, U.S. was the top producer of bentonite with almost one-third world share followed by China and Greece, reports the British Geological Survey.
The absorbent clay was given the name bentonite by an American geologist sometime after its discovery in about 1890 — after the Benton Formation (a geological stratum, at one time Fort Benton) in Montana's Rock Creek area. Other modern discoveries include montmorillonite discovered in 1847 in Montmorillon in the Vienne prefecture of France, in Poitou-Charentes, South of the Loire Valley.
Most high grade commercial sodium bentonite mined in the United States comes from the area between the Black Hills of South Dakota and the Big Horn Basin of Wyoming. Sodium bentonite is also mined in the southwestern United States, in Greece and in other regions of the world. Calcium bentonite is mined in the Great Plains, Central Mountains and south eastern regions of the United States. Supposedly the world's largest current reserve of bentonite is Chongzuo in China's Guangxi province.[citation needed]
It should be noted that in some countries like the UK, calcium bentonite is known as fuller's earth, a term which is also used to refer attapulgite, a mineralogically distinct clay mineral but exhibiting similar properties.
Early Americans found bentonite vital to their lives. Pioneers found moistened bentonite to be an ideal lubricant for squeaky wagon wheels. The mixture was also used as a sealant for log cabin roofing. The Indians found bentonite useful as a soap.
Small amounts of Wyoming bentonite were first commercially mined and developed in the Rock River area during the 1880s. Newer, more substantial deposits were discovered in other parts of Wyoming during the 1920s and the first processing plant in Wyoming was built during this period. Since that time many other processing plants have been built for the purpose of processing Wyoming sodium bentonite. Wyoming's Bentonite industry produced over 4.0 million tons of bentonite in 1999, with 644 mine and mill employees, and 240 contractor employees.
Wyoming bentonite is composed essentially of montmorillonite clay, also known as hydrous silicate of alumina. In more simplistic terms, the structure of bentonite is much like a sandwiched deck of cards. When placed in water, these cards or clay platelets shift apart. Bentonite attracts water to its negative face and magnetically holds the water in place. because of this unique characteristic, Wyoming bentonite is capable of absorbing 7 to 10 times its own weight in water, and swelling up to 18 times its dry volume.
Exploration for new bentonite beds is normally accomplished with auger bit drilling. Once the auger drill stem reaches the soft bentonite it sinks very rapidly, which indicates to the driller that bentonite has been found. The auger flights are then withdrawn and the "sticky" bentonite is sampled from the flights for quality analysis. Bentonite is mined by surface "open pit" methods. Various types of heavy equipment including bull dozers and rubber-tired scrapers are used to remove the shale rock overlying the bentonite.
Topsoil, as well as the underlying material, is carefully removed and stockpiled. These "overburden" materials as they are called will be placed back and reseeded once the bentonite has been removed. The bentonite which is exposed during this process can be as little as 1 1/2 feet or as much as 10 feet thick. This is the material which is mined and processed.
Many bentonite manufactures prefer to "field dry" the exposed bentonite prior to hauling it to the processing plants. This is accomplished by plowing and discing while taking advantage of the low humidity and sunny days to dry the bentonite prior to its removal. The moisture level prior to "field drying" can exceed 30%. This process will normally extract 15 to 20% of the moisture from the clay prior to hauling.
Upon arrival at the processing plants, the bentonite is placed into designated stockpiles and carried into the plant with front-end loaders. The bentonite is then dried in a long cylinder called a rotary dryer where approximately 10 to 15% of the moisture is removed. Natural gas or coal are used primarily as fuels for drying. The finished product has moisture content of 7 to 10%.
Once delivered from the rotary dryer, the bentonite is processed into either a fine powder or granulated into a small particle or flake. Packaging of the product is the last process to be undertaken. Granular bentonite is a major constituent of "scoopable" cat litter. Bentonite can be packaged in 50 lb., 100 lb. or up to 4,000 lb. super sacks. After the packaging process takes place, the bentonite is shipped either by truck or rail to the consumer. Another form of packaging is to ship direct in bulk pneumatic trucks or rail cars to the consumer.
WELL DRILLING
Drilling mud, or drilling gel, is a major component in the well drilling process. Drilling mud is crucial in the extraction of drill cuttings during the drilling process. Bentonite, when mixed with water, forms a fluid (or slurry) that is pumped through the drill stem, and out through the drill bit. The bentonite extracts the drill cuttings from around the bit, which are then floated to the surface. The drilling mud, or gel, also serves to cool and lubricate the drill bit as well as seal the drill hole against seepage and to prevent wall cave-ins
TACONITE PELLETIZING
Taconite, a low grade iron ore, has been developed as an economic source for iron. During processing, the taconite is ground into a very fine powder. The ground taconite is then mixed with small amounts of bentonite which serves as a binder to the taconite. This mixture is processed into balls or pellets. The process is finished when these pellets are sintered in rotary kilns that give the pellets a hard surface. The taconite pellets are easy to handle at this point and can be loaded into various containers for shipment to steel mills.
METAL CASTING
Bentonite serves as an economical bonding material in the molding processes associated with the metal casting industry. Bentonite, when mixed with foundry molding sands, forms a pliable bond with the sand granules. Impressions are formed into the face of the bentonite/sand mixtures. Molten metal is pored into the impressions at temperatures exceeding 2,800 F. The unique bonding characteristics of bentonite insures the durability of the mold during these high temperatures. Once the process is complete, the bentonite/sand mold can then be broken away from the casting face and reused.
CAT LITTER
In recent years, bentonite has become a major component in the manufacturing of cat litter. Because of the unique water absorption, swelling, and odor controlling characteristics of bentonite, it is ideal for use in "clumping" types of cat litters. Clumping cat litter has become widely accepted as an economical alternative to conventional non-clumping type cat litters. Because bentonite forms clumps when wet, the clumps can easily be removed and disposed of. The remainder of the unused material stays intact and can continue to be used. clumping cat box litters will last longer with less frequency of changing.
ANIMAL/POUTRY FEEDS
For many years bentonite has been used as a binder in the feed pelletizing industry. Small amounts of bentonite can be added to feed products to insure tougher, more durable pellets. By absorbing excess moisture and oils, bentonite aids in the free movement of pellets, preventing lumping and caking. Research has been conducted which indicates that bentonite has additional benefits for both animals and poultry. The bentonite used in the feed slows the digestive system and enables the animal or fowl to better utilize the feed nutrients. Other studies have shown bentonite as a useful ingredient in the control of certain toxins which affect animals and fowl.
OTHER APPLICATIONS
Bentonite has also proved helpful in sealing freshwater ponds, irrigation ditches, reservoirs, sewage and industrial water lagoons, and in grouting permeable ground. In addition, it has been used in detergents, fungicides, sprays, cleansers, polishes, ceramic, paper, cosmetics and applications where its unique bonding, suspending or gellant properties are required.
Normal Drilling Mud Properties
ELEMENT
PRECENTAGE
SiO2
66.9%
Al2O3
16.3%
H2O (Crystal)
6.0%
Fe2O3
3.3%
Na2O
2.6%
CaO
1.8%
MgO
1.5%
K2O
0.48%
TiO2
0.12%
Source: Black Hills Bentonite, LLC.
Bentonite Mining Operations by Area
Bentonite
What is Bentonite?
The term Bentonite was first used for a clay found in about 1890 in upper cretaceous tuff near Fort Benton, Wyoming. The main constituent, which is the determinant factor in the clay's properties, is the clay mineral montmorillonite. This in turn, derives its name from a deposit at Montmorillon, in Southern France.
Bentonite is a clay generated frequently from the alteration of volcanic ash, consisting predominantly of smectite minerals, usually montmorillonite. Other smectite group minerals include hectorite, saponite, beidelite and nontronite. Smectites are clay minerals, i.e. they consist of individual crystallites the majority of which are <2µm in largest dimension. Smectite crystallites themselves are three-layer clay minerals. They consist of two tetrahedral layers and one octahedral layer. In montmorillonite tetrahedral layers consisting of [SiO4] - tetrahedrons enclose the [M(O5,OH)]-octahedron layer (M = and mainly Al, Mg, but Fe is also often found). The silicate layers have a slight negative charge that is compensated by exchangeable ions in the intercrystallite region. The charge is so weak that the cations (in natural form, predominantly Ca2+, Mg2+ or Na+ ions) can be adsorbed in this region with their hydrate shell. The extent of hydration produces intercrystalline swelling. Depending on the nature of their genesis, bentonites contain a variety of accessory minerals in addition to montmorillonite. These minerals may include quartz, feldspar, calcite and gypsum. The presence of these minerals can impact the industrial value of a deposit, reducing or increasing its value depending on the application. Bentonite presents strong colloidal properties and its volume increases several times when coming into contact with water, creating a gelatinous and viscous fluid. The special properties of bentonite (hydration, swelling, water absorption, viscosity, thixotropy) make it a valuable material for a wide range of uses and applications.
Bentonite deposits are normally exploited by quarrying. Extracted bentonite is distinctly solid, even with a moisture content of approximately 30%. The material is initially crushed and, if necessary, activated with the addition of soda ash (Na2CO3). Bentonite is subsequently dried (air and/or forced drying) to reach a moisture content of approximately 15%. According to the final application, bentonite is either sieved (granular form) or milled (into powder and super fine powder form). For special applications, bentonite is purified by removing the associated gangue minerals, or treated with acids to produce acid-activated bentonite (bleaching earths), or treated with organics to produce organoclays.
Foundry: Bentonite is used as a bonding material in the preparation of molding sand for the production of iron, steel and non-ferrous casting. The unique properties of bentonite yield green sand moulds with good flowability, compactability and thermal stability for the production of high quality castings.
Cat Litter: Bentonite is used for cat litter, due to its advantage of absorbing refuse by forming clumps (which can be easily removed) leaving the remaining product intact for further use.
Pelletizing: Bentonite is used as a binding agent in the production of iron ore pellets. Through this process, iron ore fines are converted into spherical pellets, suitable as feed material in blast furnaces for pig iron production, or in the production of direct reduction iron (DRI).
Construction and Civil Engineering: Bentonite in civil engineering applications is used traditionally as a thixotropic, support and lubricant agent in diaphragm walls and foundations, in tunnelling, in horizontal directional drilling and pipe jacking. Bentonite, due to its viscosity and plasticity, also is used in Portland cement and mortars.
Environmental Markets: Bentonite's adsorption/absorption properties are very useful for wastewater purification. Common environmental directives recommend low permeability soils, which naturally should contain bentonite, as a sealing material in the construction and rehabilitation of landfills to ensure the protection of groundwater from the pollutants. Bentonite is the active protective layer of geosynthetic clay liners.
Drilling: Another conventional use of bentonite is as a mud constituent for oil and water well drilling. Its roles are mainly to seal the borehole walls, to remove drill cuttings and to lubricate the cutting head.
Oils/Food Markets: Bentonite is utilized in the removal of impurities in oils where its adsorptive properties are crucial in the processing of edible oils and fats (Soya/palm/canola oil). In drinks such as beer, wine and mineral water, and in products like sugar or honey, bentonite is used as a clarification agent.
Agriculture: Bentonite is used as an animal feed supplement, as a pelletizing aid in the production of animal feed pellets, as well as a flowability aid for unconsolidated feed ingredients such as soy meal. It also is used as an ion exchanger for improvement and conditioning of the soil. When thermally treated, it can be used as a porous ceramic carrier for various herbicides and pesticides.
Pharmaceuticals, Cosmetics and Medical Markets: Bentonite is used as filler in pharmaceuticals, and due to its absorption/adsorption functions, it allows paste formation. Such applications include industrial protective creams, calamine lotion, wet compresses, and antiirritants for eczema. In medicine, bentonite is used as an antidote in heavy metal poisoning. Personal care products such as mud packs, sunburn paint, baby and facepowders, and face creams may all contain bentonite.
Detergents: Laundry detergents and liquid hand cleansers/soaps rely on the inclusion of bentonite, in order to remove the impurities in solvents and to soften the fabrics.
Paints, Dyes and Polishes: Due to its thixotropic properties, bentonite and organoclays function as a thickening and/or suspension agent in varnishes, and in water and solvent paints. Its adsorption properties are appreciated for the finishing of indigo dying cloth, and in dyes (lacquers for paints & wallpapers).
Paper: Bentonite is crucial to paper making, where it is used in pitch control, i.e. absorption of wood resins that tend to obstruct the machines and to improve the efficiency of conversion of pulp into paper as well as to improve the quality of the paper. Bentonite also offers useful de-inking properties for paper recycling. In addition, acid-activated bentonite is used as the active component in the manufacture of carbonless copy paper.
Catalyst: Chemically-modified clay catalysts find application in a diverse range of duties where acid catalysis is a key mechanism. Most particularly, they are employed in the alkylation processes to produce fuel additives.
Succes for You All,
Michael S. Thang
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Tuesday, 19 August 2008
Shell's Omega MEG process kicks off in South Korea
12 August 2008 00:00 [Source: ICB]
The first full-scale plant using Shell's catalytic MEG process has just come on stream. One ICIS reporter investigates what the technology offers
THE "HOLY Grail" for a process engineer could be the development of a technology that converts all the raw materials to the desired end product with the minimum theoretical energy consumption, no emissions and the lowest capital cost.
While this may be a fantastic but vain hope, in the highly competitive petrochemical industry, particularly with today's high feedstock and energy costs, just a few percentage points of improvement in process performance can push a technology into a leadership position.
In the case of monoethylene glycol (MEG) technology, the holy grail could be the complete conversion of ethylene oxide (EO) to MEG without any production of the higher glycols such as diethylene glycol (DEG). However, this near-impossible goal did not stop researchers at Japan's Mitsubishi Chemical developing a catalytic process that converts practically all the EO into MEG.
Shell Global Solutions, the oil major's global consulting arm, has integrated Mitsubishi's MEG process with its own EO technology to offer the OMEGA process. The first plant incorporating the integrated process is now operating in South Korea, with a second unit in Saudi Arabia due to start up in the next few months.
Piet van den Berg, licensing manager, Shell EO/EG (ethylene glycol) processes, explains: "The global MEG market is growing at 6-7%/year, driven by polyester fiber demand in Asia and demand for PET [polyethylene terephthalate] packaging resin. However, there has been a mismatch of demand, with the DEG market growing at less than 6%/year and so the trend has been to maximize the yield of MEG."
Van den Berg adds that there are two areas where MEG yields can be maximized: improving EO selectivity and MEG selectivity.
EO is produced by the direct oxidation of ethylene, with high purity oxygen over a catalyst containing silver at temperatures of about 230-270°C (440-518°F). A side reaction competing with the main reaction forms carbon dioxide (CO2) and water. This reaction is suppressed using an ethyl chloride moderator. The CO2 is recovered and removed from the process.
In the early 1960s, when today's conventional technology was first being commercialized, EO selectivity was around 65%, with the main by-product being CO2. With the latest catalysts, van den Berg notes that EO selectivity is now approaching 90%.
In the EO to EG step, excess water is used to increase the selectivity to MEG. In the conventional process, the EO-water mixture is heated to around 200°C and the reaction takes place in the aqueous phase under pressure. MEG is produced along with DEG, triethylene glycol (TEG) and other glycols.
The proportion of the higher glycols can be controlled using excess water to minimize the reaction between the EO and glycols, and the water:EO ratio is critical in determining the volumes of higher glycols produced. In Shell's conventional process, a MEG selectivity of 90% is achieved with a H2O:EO ratio (wt/wt) of 9:1. The water-glycol mixture from the reactor is fed to multiple evaporators where the water is recovered and recycled. The water-free glycol mixture is separated by distillation into the MEG and the higher glycols. This operation consumes a lot of energy and requires purification, storage and handling equipment for the by-products.
In the past 10 years, the main EG licensors, which include Shell, have carried out research in using ion exchange resins to enhance the MEG selectivity. According to van den Berg, these resins can achieve a selectivity of 95% and above, but there is still a need for excess water of a H2O:EO ratio (wt/wt) of 6:1.
TWO-STEP PROCESS
However, Mitsubishi Chemical took a different approach, which involved the use of a catalyst and water:EO ratio approaching stoichiometric levels. This conversion is carried out in two reaction steps in order to achieve a high selectivity to MEG.
The first step in the process is the reaction of EO with dissolved CO2 to produce ethylene carbonate (EC). The CO2 is obtained from the CO2 produced and recovered in the EO plant. However, at start-up, the CO2 is supplied from a liquid storage tank. The second step is the reaction of EC with water, present in slight excess, to form MEG. In this reaction, the CO2 consumed in the first reaction is released and recycled back to the EC reactor, resulting in no overall CO2 consumption.
The EC reaction is exothermic (24 kcal/gmole) and the EC hydrolysis reaction slightly endothermic (-2 kcal/gmole). Both take place in the liquid phase using a set of homogeneous catalysts such as phosphonium halide.
The mixture from the EC hydrolysis reactors is fed to a glycol dehydrator to remove the water. The glycol stream containing the catalyst is then sent to the separation section at the bottom of the MEG purification column.
The catalyst solution is recycled back to the EC reactor. A small bleed is taken from the catalyst recycle stream to limit the build-up of heavy components and fresh catalyst can be added. The MEG is flashed off and sent to the top section of the purification column, where the finished MEG is recovered. A stream of heavy glycols, mainly DEG, is separated and sent to storage for further processing.
From 1995, Mitsubishi spent six years of process research and development taking the technology from bench scale to a pilot plant and then to a semi-commercial unit. It first tested the process in a 1,000 tonne/year pilot plant and then built a 15,000 tonne/year demonstration plant to scale up the technology. The MEG produced was tested in a third-party PET plant to check it was fully compatible with MEG from a conventional process.
Shell Global Solutions acquired the Mitsubishi technology in 2002 and became its exclusive licensor. The two firms then carried out a joint design exercise to integrate the Mitsubishi MEG technology with the Shell EO process and to solve scale-up problems with the reactors and separators. Risk, health and safety assessments were also performed.
Van den Berg claims that the selectivity of EO to MEG for the Shell OMEGA process is 99.3-99.5% and it can produce up to 1.95 tonnes of MEG from 1 tonne of ethylene. This conversion compares to 1.53-1.70 tonnes produced by Shell's conventional process, depending on the EO catalyst used.
The OMEGA process is also claimed to have 10% lower capital costs than a conventional process of equal MEG capacity. Much of the savings are due to the elimination of the need to treat the by-products and waste water. Steam consumption is 20% lower, while 30% less waste water is produced.
Since 2004, Shell has sold five licences. The first commercial plant, with a capacity of 400,000 tonnes/year, using the OMEGA process was started up in Daesan, South Korea, for Lotte Daesan Petrochemical in May 2008. The project was implemented in only 29 months, notes Arthur Rots, Shell's EO/EG design group leader. From a kickoff meeting in January 2006, the basic design package was produced by July 2006. South Korea's Samsung Engineering was responsible for the engineering, procurement and construction phase, with mechanical completion in March 2008. Start-up was achieved on May 21, and the guarantee test runs completed on June 1.
The second OMEGA plant, with a MEG capacity of 600,000 tonnes/year, to be operated by PetroRabigh, a joint venture of Saudi oil company Saudi Aramco and Japan's Sumitomo Chemical, in Saudi Arabia, is due to be completed in late 2008. Shell will employ the process in its own 750,000 tonne/year plant in Singapore due for start-up in early 2010. Read More..
US ethylene poised to trend downwards
August 2008 21:02 [Source: ICIS news]
By Stephen Burns
HOUSTON (ICIS news)--Buyers were already marshalling their arguments for a cut of 5 cents/lb or more in US Gulf August ethylene contracts as supply loosens amid soft demand and tumbling spot prices, sources said on Friday.
A fall in the August contract would be only the second decline since a steep climb began in April 2007, and it could mark the sea change that buyers have been hoping would come from the month-long reversal of crude oil's earlier rally.
In an unusual double-month settlement, US Gulf net contracts for June were finalised last week with a 5 cent/lb ($110/tonne or €72/tonne) increase to 70.5 cents/lb.
A contemporaneous agreement was reached for an increase of 4 cents/lb for July, according to data from global chemical market intelligence service ICIS pricing
Including the July increase, the net contract price at 74.5 cents/lb has now soared 89% from the April 2007 low, with a 3 cent/lb drop in February this year as the only blip in the upward trend.
Buyers pointed to improved margins and high operating rates for the loosening of supply, as well as a relatively smooth record of cracker operations.
The arrival of the relatively mild Tropical Storm Edouard near Houston on Tuesday did not dent that track record.
Only minor issues surfaced, such as a power outage that lasted less than two hours at the 200,000 tonne/year Port Neches plant in Texas operated by Huntsman.
The change in ethylene market sentiment has manifested most clearly in the spot market's deep discount to contract values.
August material moved down from a deal at 52.75 cents/lb at the start of the week to 49 cents/lb done on Wednesday, with current price ideas around 47 cents/lb. One buyer expected 45 cents/lb to be traded soon.
Downstream, sources said some polyethylene (PE) producers were quietly postponing their proposed August price hikes as monomer values sank.
However, future price indications give ethylene sellers some room for hope that the slide might not gather too much momentum. The fall in the prompt spot market has flattened the backwardation in the forward curve, with December price ideas notionally at 46.25 cents/lb, according to one broker.
That 0.75 cent/lb gap to prompt material is narrower than the 1.25 cents/lb gap seen at the end of last week.
Producers’ arguments in favour of at least maintaining contract prices are also being undermined by the slump in ethane, the dominant feedstock for US Gulf crackers.
Ethane values peaked alongside crude at around $1.50/gal in early July but have since declined by around a third and were only just above $1.00/gal as the week drew to a close.
That is even sharper than the 21% decline in NYMEX crude oil futures since the 11 July peak at $147.27/bbl.
Still, Tropical Storm Edouard - which had not even entered market consciousness two just days before it set off a hurricane alert in Houston - underscored the potential for the rosy supply picture to change.
In September 2007, another pop-up storm rapidly developed into Hurricane Humberto. That storm made landfall in east Texas and caused extended stoppages at three crackers as well as three refineries, giving an upward bump to ethylene prices.
The official hurricane season runs until 30 November.
(Additional reporting by David Barry)
($1 = €0.65)
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Thursday, 14 August 2008
Asia Price rises, Euro Drop to Fan Eurozone Inflation
Asia price rises,euro drop to fan eurozone inflation
Thu Aug 14 18:46:36 PDT 2008
By Marc Jones
FRANKFURT, August 14 (Reuters) - Inflation-fighting European central bankers may be rejoicing at the 20 percent drop in oil prices, but a combination of soaring Asian prices and a recent sharp fall in the euro threatens to spoil the party.
A 7.5 percent drop in the euro against the dollar over the last month is making goods European firms source from abroad substantially more expensive, while high Asia-wide inflation is forcing up prices of goods from the region from t-shirts to TVs.
In China, inflation is over 7 percent, and while producer price data may show low single-digit increases, the impact is amplified by the fact that prices of Chinese goods were actually dropping until recently.
The story is the same across the region. Oil, food and commodity prices have tipped Indian inflation over 12 percent for the first time in 13 years. Indonesian inflation is at 12.2 percent, Philippine inflation at a 17-year high and in Thailand it has jumped to almost 10 percent.
As Asian suppliers push through price rises the whole world suffers but the fall in the euro over the last month is making life particularly hard for companies based in Europe.
That is because they usually pay big Asian suppliers in dollars and while until recently the euro's strength cocooned them from price rises, that protection is rapidly disappearing.
"The euro had risen very sharply against the dollar...this had a very substantial limiting effect on the impact of this Asian inflation pressure... but with the dollar now strengthening against the euro this now presents a greater risk," said Barclays Capital analyst Julian Callow.
"While we may have seen commodity prices moderate, paradoxically the impact of the weaker euro, if it were to continue, means we could be actually get more inflation pressure from Asian manufactured goods."
Evidence from European firms that Asian producers are upping prices is plentiful.
"In terms of suppliers... we have to accept increases due to inflationary pressure and wage pushes, which make products manufactured in Asia and elswhere in the world more expensive," German sportswear maker Puma's Chief Executive Jochen Zeitz said last week.
"All this has a certain impact on the cost structure of products. For 2009 we are now thinking about how to raise prices selectively."
And while the sharp drop in oil prices should cool inflation in the euro zone, higher pricetags on goods sourced from Asia would act as a prop.
"The euro area might get relief on the inflation front from weaker energy and food inflation but it might find core inflation is persistent and may ultimately push up higher partly because of this imported inflation on consumer goods," said Callow.
LONG FUSE
Other economists are more sceptical about the possible impact of Asian inflation on the euro-zone's harmonised index of consumer prices (HICP), running at 4.0 percent in July.
"Given the current structure of the HICP basket, assuming the euro trade-weighted index stays at current levels, I would say the impact (on inflation) would be quite limited, I wouldn't go above 0.1-0.2 percentage points," said UniCredit analyst Aurelio Maccario.
"The story would be different if we see an outright plunge in the euro but that is not our baseline assumption."
The key factor could be if Asian suppliers absorb some of the impact of home-grown inflation on their margins as the rapid slowdown in the United States and much of Europe tempers demand.
"I think the impact of the manufactured goods price inflation from Asia may be being dampened at the moment by the weakness in the U.S. economy. The full implictions of this might not come through until we see a more buoyant global economy again," said Callow.
Others back up that idea. Last month Goldman Sachs nudged down their Asian 2008 and 2009 growth forecasts calculating that the slowdown was starting to grip.
But most economists agree that while inflation in Asia will soon peak, it will remain a slow burning problem as rising personal wealth buoys demand, central banks keep accomodative interest rates and governments slash food and fuel subsides.
"While we see inflation possibly peaking in some countries in Q3 2008, we do not foresee the consumer price inflation receding back to benign levels anytime soon," Deutsche Bank analysts wrote in a recent note.
"We expect inflation to remain at elevated levels over the medium term, despite the decline in oil prices. Anecdotal evidence suggests that within 5 years, western-style salaries may be required in developing Asia to attract talent."
(Additional reporting by Eva Kuehnen; Editing by Gerrard Raven)
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Michael S. Thang
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Tuesday, 12 August 2008
Base Oil, Lubricant
LUBRICANT BASE OIL
Lubricant oils are produced from Parafinic & Naphtenic Stock.
3 basic types of crude oil :
> 1. Parafinic
> 2. Iso-Parafinic Napthtenic
> 3. Aromatic, Asphaltic
Lubricant formulation guide :
1. Additives
2. Lube base oil 80-90 %
Lube base divided into 5 parts :
1. Group 1
VI ( Viscosity Index = the lower the VI, the larger a change in viscosity with
temp. changes ) = 80-120, component Lube base > 90 %, Sulfur <>
2. Group 2
VI = 80-120, component Lube base oil > 90 %, Sulfur <>
3. Group 3
VI > 120, component Lube base oil > 90 %, sulfur <>
4. Group 4
PAO ( Poly Alpha Olefin ), Lube base oil mostly used for car race.
PAO hasve had superior performance characterictic such as Viscosity Index
( VI ), Pour Point,
Volatility and Oxidation stability that it could not be achieved by convention
mineral oil. With modern base oil manufacturing, VI, Pour Point, Volatility &
Oxidation stability all can be independently controlled.
5. Group 5
Exlude Group I - IV.
Notes : Group I & II as conventional based oil.
Group III-V as synthetic based oil.
Dubase Oil as Group III stock is available, please contact me.
Succes for you all,
Michael S. Thang
chemical_info@yahoo.com
Read More..
Lubricant oils are produced from Parafinic & Naphtenic Stock.
3 basic types of crude oil :
> 1. Parafinic
> 2. Iso-Parafinic Napthtenic
> 3. Aromatic, Asphaltic
Lubricant formulation guide :
1. Additives
2. Lube base oil 80-90 %
Lube base divided into 5 parts :
1. Group 1
VI ( Viscosity Index = the lower the VI, the larger a change in viscosity with
temp. changes ) = 80-120, component Lube base > 90 %, Sulfur <>
2. Group 2
VI = 80-120, component Lube base oil > 90 %, Sulfur <>
3. Group 3
VI > 120, component Lube base oil > 90 %, sulfur <>
4. Group 4
PAO ( Poly Alpha Olefin ), Lube base oil mostly used for car race.
PAO hasve had superior performance characterictic such as Viscosity Index
( VI ), Pour Point,
Volatility and Oxidation stability that it could not be achieved by convention
mineral oil. With modern base oil manufacturing, VI, Pour Point, Volatility &
Oxidation stability all can be independently controlled.
5. Group 5
Exlude Group I - IV.
Notes : Group I & II as conventional based oil.
Group III-V as synthetic based oil.
Dubase Oil as Group III stock is available, please contact me.
Succes for you all,
Michael S. Thang
chemical_info@yahoo.com
Read More..
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