Acetic acid fermentation is one kind of oxidation fermentation. It is a process that ethanol oxidation into acetic acid under the effect of acetic acid bacteria. Besides there are many kinds of microorganisms can also form acetic acid with various compounds through anaerobic activity. But it generally not called acetic acid fermentation.
Acetic acid bacteria is aerobic bacteria. Fermentation is making under aeration conditions and always with the temperature of the range from 25 to 30 centigrade. Acetic acid bacteria need amino acids and vitamins. So there must be adding yeast extract, koji and other organic matter with nitrogen containing to the fermentation liquid.
There are two types of brewing vinegar, they are solid fermentation and liquid fermentation. For example, for saccharification and alcohol fermentation with the original material of starch, finally making acetic acid fermentation. Solid state fermentation is traditional crafts. There are many kinds of microorganisms participate in and product flavor is good. Liquid fermentation is general for industrialized production. It uses pure culture of the fungus and with large output,lower cost, but the flavor is bad.
Vinegar as a life essential items has the important position in food flavoring. Acetic acid can inhibit the growth of spoilage bacteria. You can be kept vegetables fresh and not corruption with vinegar pickled. Acetic acid can also be used as a medical disinfectant. Glacial acetic acid is an important raw material for chemical and pharmaceutical, widely used in printing and dyeing industry. Acetic acid are also widely used in textile industry, fiber industry, pesticide industry, dyestuff industry, plastic industry and others.
Tuesday, June 24, 2014
Tuesday, June 17, 2014
Using Acetic Acid Carefully
Acetic acid has corrosive. Its irritation has effect on steam eye and nose. So we should be more careful in using the acetic acid. If the skin contact with acetic acid. You should wash with water first, then use the soap to wash thoroughly. Certainly you should be careful when the acetic acid get into your eyes. Wash your eyes with water at first and then clean with dry cloth. If it is serious, you must go to the hospital immediately. In order to avoid these accident, you can wear protective glasses which with chemical safety in the working and wear rubber gloves. After working, you should take a shower and change your clothes. Don’t take the work clothes into the living area. When concentration in the air is exceed the standard, you should wear masks.
We have 99.9%min glacial acetic acid,99.8%min glacial acetic acid,90%min glacial acetic acid,80%min glacial acetic acid or according to the special requirement by customer. Annual capacity of our glacial acetic acid is 350,000. The raw material is methanol.If you swallow the acetic acid, you must be given an emetic and go to hospital. Likewise it is also dangerous to inhaled acetic acid vapor. Far away from the pollution areas to rest and keep warm at the same time.
We have 99.9%min glacial acetic acid,99.8%min glacial acetic acid,90%min glacial acetic acid,80%min glacial acetic acid or according to the special requirement by customer. Annual capacity of our glacial acetic acid is 350,000. The raw material is methanol.If you swallow the acetic acid, you must be given an emetic and go to hospital. Likewise it is also dangerous to inhaled acetic acid vapor. Far away from the pollution areas to rest and keep warm at the same time.
Wednesday, April 16, 2014
The Methanol Storage
Methanol is an important organic chemical raw materials, and it is widely used in many industry. It can produce formaldehyde, synthetic rubber, methyl chloride,acetic acid and a series of organic chemical products. It is also used for the synthesis of methanol protein.
Methanol consumption structure in our country is similar to foreign countries, and the largest the consumption field is formaldehyde production. The proportion of consumption is about 40%. The second is MTBE and acetic acid, the proportion is 6% and 7% respectively. However with the needing of protecting the environment and the world oil resources become increasingly scarce, the development of methanol fuel consumption become fast in recent year. It becomes one of the majority power of methanol demand. In addition,along with the two ether entered the civil gas market officially, the demand for methanol is expansion quickly. Now the methanol and its downstream products is most likely to become the leading alternative products for the the beginning of the post petroleum Era.
Most suitable storage container to methanol is stainless steel containers and plastic tank. The plastic tank use pure polyethylene as raw material and it uses a special rotational molding process to molding the whole. The plastic tan has many advantages, such as no welding, no leakage, non-toxic, light weight, impact resistance, corrosion resistance, integrated and long life. Certainly, it also could store most inorganic acid, alkali, salt solution and most organic solvents, while can partly replace titanium, stainless steel, high nickel alloy steel and other materials. The production is meet the storage and transportation of dangerous goods regulations and a ideal storage container for methanol and reaction chemical corrosion, clean solution. Methanol in line with national health standards,can replace the stainless steel container to shipment.
Methanol consumption structure in our country is similar to foreign countries, and the largest the consumption field is formaldehyde production. The proportion of consumption is about 40%. The second is MTBE and acetic acid, the proportion is 6% and 7% respectively. However with the needing of protecting the environment and the world oil resources become increasingly scarce, the development of methanol fuel consumption become fast in recent year. It becomes one of the majority power of methanol demand. In addition,along with the two ether entered the civil gas market officially, the demand for methanol is expansion quickly. Now the methanol and its downstream products is most likely to become the leading alternative products for the the beginning of the post petroleum Era.
Most suitable storage container to methanol is stainless steel containers and plastic tank. The plastic tank use pure polyethylene as raw material and it uses a special rotational molding process to molding the whole. The plastic tan has many advantages, such as no welding, no leakage, non-toxic, light weight, impact resistance, corrosion resistance, integrated and long life. Certainly, it also could store most inorganic acid, alkali, salt solution and most organic solvents, while can partly replace titanium, stainless steel, high nickel alloy steel and other materials. The production is meet the storage and transportation of dangerous goods regulations and a ideal storage container for methanol and reaction chemical corrosion, clean solution. Methanol in line with national health standards,can replace the stainless steel container to shipment.
Thursday, October 24, 2013
Isobutanol
Isobutanol is
an organic compound with the formula (CH3)2CHCH2OH. This colorless,
flammable liquid with a characteristic smell is mainly used as a
solvent. Its isomers include n-butanol, 2-butanol, and tert-butanol, all
of which are important industrially.
Isobutanol is produced by the carbonylation of propylene. Two methods are practiced industrially, hydroformylation is more common and generates a mixture of isobutyraldehydes, which are hydrogenated to the alcohols and then separated. Reppe carbonylation is also practiced.
And isobutanol could indeed function as a relatively effective substitute for gasoline — isobutanol releases just around 82% of the heat energy that gasoline does when burned, as compared to the 67% that ethanol does. And, perhaps more importantly, isobutanol doesn’t possess the same significant drawbacks that ethanol does — in particular, it doesn’t possess ethanol’s unfortunate tendency to absorb water, and thus doesn’t damage conventional engines and pipelines in the same way that pure ethanol does. So, while pure ethanol would only be a viable replacement for gasoline if all of the infrastructure in use today was completely replaced, isobutanol cold simply replace gasoline as is — no new infrastructure needed.
Isobutanol — a high-performance biofuel that closely matches the properties of gasoline — can be produced from waste plant materials through the combined actions of a common fungus and a common bacteria, according to new research from the University of Michigan. When paired up together, the fungus Trichoderma reesei, and the bacteria Escherichia coli, can effectively create the biofuel isobutanol from materials such as cornstalks and plant leaves.
While the production of a useful biofuel is impressive enough, the researchers think that the same principle used to produce the biofuel could be used to produce other useful chemicals, such as plastics.
Isobutanol is also produced naturally during the fermentation of carbohydrates and may also be a byproduct of the decay process of organic matter. The biosynthetic pathway used to produce isobutanol was first discovered in species of bacteria from the genus Clostridium. This pathway has been genetically engineered into several species of microorganisms which are more easily manipulated by current scientific methods than microorganisms of the genus Clostridium.
And isobutanol could indeed function as a relatively effective substitute for gasoline — isobutanol releases just around 82% of the heat energy that gasoline does when burned, as compared to the 67% that ethanol does. And, perhaps more importantly, isobutanol doesn’t possess the same significant drawbacks that ethanol does — in particular, it doesn’t possess ethanol’s unfortunate tendency to absorb water, and thus doesn’t damage conventional engines and pipelines in the same way that pure ethanol does. So, while pure ethanol would only be a viable replacement for gasoline if all of the infrastructure in use today was completely replaced, isobutanol cold simply replace gasoline as is — no new infrastructure needed.
Edit by http://www.hiseachem.com
Isobutanol is produced by the carbonylation of propylene. Two methods are practiced industrially, hydroformylation is more common and generates a mixture of isobutyraldehydes, which are hydrogenated to the alcohols and then separated. Reppe carbonylation is also practiced.
And isobutanol could indeed function as a relatively effective substitute for gasoline — isobutanol releases just around 82% of the heat energy that gasoline does when burned, as compared to the 67% that ethanol does. And, perhaps more importantly, isobutanol doesn’t possess the same significant drawbacks that ethanol does — in particular, it doesn’t possess ethanol’s unfortunate tendency to absorb water, and thus doesn’t damage conventional engines and pipelines in the same way that pure ethanol does. So, while pure ethanol would only be a viable replacement for gasoline if all of the infrastructure in use today was completely replaced, isobutanol cold simply replace gasoline as is — no new infrastructure needed.
Isobutanol — a high-performance biofuel that closely matches the properties of gasoline — can be produced from waste plant materials through the combined actions of a common fungus and a common bacteria, according to new research from the University of Michigan. When paired up together, the fungus Trichoderma reesei, and the bacteria Escherichia coli, can effectively create the biofuel isobutanol from materials such as cornstalks and plant leaves.
While the production of a useful biofuel is impressive enough, the researchers think that the same principle used to produce the biofuel could be used to produce other useful chemicals, such as plastics.
Isobutanol is also produced naturally during the fermentation of carbohydrates and may also be a byproduct of the decay process of organic matter. The biosynthetic pathway used to produce isobutanol was first discovered in species of bacteria from the genus Clostridium. This pathway has been genetically engineered into several species of microorganisms which are more easily manipulated by current scientific methods than microorganisms of the genus Clostridium.
And isobutanol could indeed function as a relatively effective substitute for gasoline — isobutanol releases just around 82% of the heat energy that gasoline does when burned, as compared to the 67% that ethanol does. And, perhaps more importantly, isobutanol doesn’t possess the same significant drawbacks that ethanol does — in particular, it doesn’t possess ethanol’s unfortunate tendency to absorb water, and thus doesn’t damage conventional engines and pipelines in the same way that pure ethanol does. So, while pure ethanol would only be a viable replacement for gasoline if all of the infrastructure in use today was completely replaced, isobutanol cold simply replace gasoline as is — no new infrastructure needed.
Edit by http://www.hiseachem.com
Friday, October 11, 2013
Have a knowledge of phenol
A phenol
is one of a number of chemically active compounds which are found
throughout nature, especially in plants. Their molecules each include a
hydroxyl functional group (OH) bonded to the ring of an aromatic compound
— a molecule that includes at least one ring of carbon atoms. Phenols
exhibit a wide range of properties; some are heralded for their health
benefits, while others are deadly poisons. Some have important
industrial uses as drugs or food additives. The word phenol may also refer to carbolic acid (C6H5OH), the simplest of this group of chemicals.
Phenol is the simplest member of a family of compounds in which an -OH group is attached directly to a benzene ring. Phenol itself is the only one of the family that you are likely to need to know about for UK A level purposes.
There is an interaction between the delocalised electrons in the benzene ring and one of the lone pairs on the oxygen atom. This has an important effect on both the properties of the ring and of the -OH group.
Pure phenol is a white crystalline solid, smelling of disinfectant. It has to be handled with great care because it causes immediate white blistering to the skin. The crystals are often rather wet and discoloured.
Phenol is so inexpensive that it attracts many small-scale uses. It once was widely used as an antiseptic, especially as carbolic soap, from the early 1900s through the 1970s. It is a component of industrial paint strippers used in the aviation industry for the removal of epoxy, polyurethane and other chemically resistant coatings. Phenol derivatives are also used in the preparation of cosmetics including sunscreens, hair colorings, and skin lightening preparations. Concentrated phenol liquids are commonly used in the surgical treatment of ingrown toenails to prevent a section of the toenail from growing back. This process is called phenolization.
When phenol donates a hydrogen ion to water, the electron pair remaining on the oxygen atom becomes delocalized, meaning that it becomes redistributed into the phenyl ring and cannot be assigned with certainty to any one pair of atoms. This effect is possible because of the π bonds in the phenyl ring (bonds that form between overlapping unhybridized p-orbitals). In cyclohexanol, on the other hand, all of the carbons in the ring structure share single bonds and there are no π bonds, so the negative charge on the oxygen does not become delocalized if the hydrogen is donated to water.
In a phenol extraction, the acidity of the whole mixture is important to effectively extract the DNA and RNA. Chemists recommend that the phenol should have a pH higher than 7 so that the water layer can successfully gather the DNA. At a pH of 4.5, which is already considered acidic, the RNA can already be gathered by the water phase. To change the phenol’s acidity or alkalinity, some chemicals are added, such as the compound tris or N-ethylmorpholine.
Edit by http://www.hiseachem.com
Phenol is the simplest member of a family of compounds in which an -OH group is attached directly to a benzene ring. Phenol itself is the only one of the family that you are likely to need to know about for UK A level purposes.
There is an interaction between the delocalised electrons in the benzene ring and one of the lone pairs on the oxygen atom. This has an important effect on both the properties of the ring and of the -OH group.
Pure phenol is a white crystalline solid, smelling of disinfectant. It has to be handled with great care because it causes immediate white blistering to the skin. The crystals are often rather wet and discoloured.
Phenol is so inexpensive that it attracts many small-scale uses. It once was widely used as an antiseptic, especially as carbolic soap, from the early 1900s through the 1970s. It is a component of industrial paint strippers used in the aviation industry for the removal of epoxy, polyurethane and other chemically resistant coatings. Phenol derivatives are also used in the preparation of cosmetics including sunscreens, hair colorings, and skin lightening preparations. Concentrated phenol liquids are commonly used in the surgical treatment of ingrown toenails to prevent a section of the toenail from growing back. This process is called phenolization.
When phenol donates a hydrogen ion to water, the electron pair remaining on the oxygen atom becomes delocalized, meaning that it becomes redistributed into the phenyl ring and cannot be assigned with certainty to any one pair of atoms. This effect is possible because of the π bonds in the phenyl ring (bonds that form between overlapping unhybridized p-orbitals). In cyclohexanol, on the other hand, all of the carbons in the ring structure share single bonds and there are no π bonds, so the negative charge on the oxygen does not become delocalized if the hydrogen is donated to water.
In a phenol extraction, the acidity of the whole mixture is important to effectively extract the DNA and RNA. Chemists recommend that the phenol should have a pH higher than 7 so that the water layer can successfully gather the DNA. At a pH of 4.5, which is already considered acidic, the RNA can already be gathered by the water phase. To change the phenol’s acidity or alkalinity, some chemicals are added, such as the compound tris or N-ethylmorpholine.
Edit by http://www.hiseachem.com
Tuesday, September 17, 2013
Methylal
Methylal is a new type of solvent. Methylal has the characteristics
of solubility, no toxicity and no air pollution. Methylal can replace
traditional solvent of acetone, benzene, toluene, Freon, etc. and can be
used in the industries of fungicides, industrial detergents, leather
polishing agent, cosmetics, pharmaceuticals, etc. Methylal greatly
reduces the discharge of toxic organic compounds and reduces atmospheric
pollution. Methylal is a green and environmentally friendly product and
has a broad development prospect.
Methylal, also called dimethoxymethane (DMM), has the molecular formula CH3O-CH2-OCH3. It is a liquid at ambient temperature and pressure, with a boiling point of 42.3°C, flash point of -17.8°C and a melting point of -104.8°C.
Methylal hazards and first aid measures
Methylal is irritating to mucous membrane and has anesthetic effects. Inhalation of vapors may cause nose and throat irritation. Inhalation of high-concentration methylal can cause dizziness and other symptoms. Methylal is harmful to the eyes and the hurt can last for several days. Long-term methylal contact can cause dry skin.
Methylal is a condensation product of methanol and formaldehyde and has low toxicity and corrosiveness, which makes it an ideal substitute solvent for benzene, toluene, xylene, acetone, etc. which are for example commonly used in painting industries.
First aid measures
Skin Contact: Remove contaminated clothing, and wash the skin thoroughly with soap and water.
Eye contact: Lift the eyelids; Wash the eyes with moving water or saline water, and go to see a doctor.
Methylal inhalation: Rapidly move from the scene to places with fresh air; maintain the respiratory tract clear; if breathing is difficult, oxygen should be provided; if breathing stops, artificial respiration should be immediately carried out, and a doctor should be sent.
Methylal ingestion: Drink enough warm water; apply the emetic method and go to see a doctor.
Methylal clean production technology
Methylal has excellent physical and chemical properties, good degreasing capability and volatile property. Methylal can be used as detergent for replacing F11, F113, and chlorinated solvents. Therefore, methylal is a environmental protective product for replacing Freon to reduce volatile organic compounds (VOCs) emissions and reduce air pollution. Due to its dissolution characteristic, methylal can be used as a substitute for part of the halogen hydrocarbon solvent. Methylal has good miscibility with many solvents, especially LPG, of DME. Methylal has low boiling point which is helpful to improve the steam pressure and atomization rate of aerosol. Methylal has excellent solubility in water and provides good prospects for the development of water-based aerosol.
As methylal is regarded as being an environmentally friendly solvent, it can replace many of the oil downstream products of which are relatively toxic solvents and chemicals. In the past two years, China in particular has led the way and implemented methylal use in many areas.
Production technology of high-concentration methylal
Methylal synthesis uses sulfuric acid as catalyst at all times, but the sulfuric acid has severe corrosion to the equipment. With the development of methylal technology, solid resin is used as catalyst, the combination technique of reaction and distillation is developed, and then yield and quality are greatly improved. With the help of methylal plant, general-concentration methylal is processed into low-concentration methylal, 92% methylal is pressed into the differential pressure distillation column for pressure distillation. Pressure is controlled at 1.2-1.5Mpa, the top temperature of the distillation column is controlled at 120 ℃, and the bottom temperature of the distillation column is controlled at 135 ℃. High concentration methylal is produced at the bottom, distillate at the top of column flow back to the reaction column and thepressure distillation column.
The combination of methylal physical properties such as low molecular weight, minimal viscosity and high solvent power make methylal an ideal candidate for application in environmentally friendly paint strippers.
How far does methanol-formaldehyde-methylal chain can go?
The methylal technology is produced by the condensation reaction of methanol and formaldehyde. The operation of a huge amount of methylal devices brings more space for methanol demands. The chain of methanol-formaldehyde-methylal looks stable and has good demand support. The demands are increased for methanol and formaldehyde plant enterprises of overcapacity. However, a series of market performance reflects the market space of methylal is very small, and the chain of methanol-formaldehyde-methylal chain will be at the risk of out of control.
Methylal, also called dimethoxymethane (DMM), has the molecular formula CH3O-CH2-OCH3. It is a liquid at ambient temperature and pressure, with a boiling point of 42.3°C, flash point of -17.8°C and a melting point of -104.8°C.
Methylal hazards and first aid measures
Methylal is irritating to mucous membrane and has anesthetic effects. Inhalation of vapors may cause nose and throat irritation. Inhalation of high-concentration methylal can cause dizziness and other symptoms. Methylal is harmful to the eyes and the hurt can last for several days. Long-term methylal contact can cause dry skin.
Methylal is a condensation product of methanol and formaldehyde and has low toxicity and corrosiveness, which makes it an ideal substitute solvent for benzene, toluene, xylene, acetone, etc. which are for example commonly used in painting industries.
First aid measures
Skin Contact: Remove contaminated clothing, and wash the skin thoroughly with soap and water.
Eye contact: Lift the eyelids; Wash the eyes with moving water or saline water, and go to see a doctor.
Methylal inhalation: Rapidly move from the scene to places with fresh air; maintain the respiratory tract clear; if breathing is difficult, oxygen should be provided; if breathing stops, artificial respiration should be immediately carried out, and a doctor should be sent.
Methylal ingestion: Drink enough warm water; apply the emetic method and go to see a doctor.
Methylal clean production technology
Methylal has excellent physical and chemical properties, good degreasing capability and volatile property. Methylal can be used as detergent for replacing F11, F113, and chlorinated solvents. Therefore, methylal is a environmental protective product for replacing Freon to reduce volatile organic compounds (VOCs) emissions and reduce air pollution. Due to its dissolution characteristic, methylal can be used as a substitute for part of the halogen hydrocarbon solvent. Methylal has good miscibility with many solvents, especially LPG, of DME. Methylal has low boiling point which is helpful to improve the steam pressure and atomization rate of aerosol. Methylal has excellent solubility in water and provides good prospects for the development of water-based aerosol.
As methylal is regarded as being an environmentally friendly solvent, it can replace many of the oil downstream products of which are relatively toxic solvents and chemicals. In the past two years, China in particular has led the way and implemented methylal use in many areas.
Production technology of high-concentration methylal
Methylal synthesis uses sulfuric acid as catalyst at all times, but the sulfuric acid has severe corrosion to the equipment. With the development of methylal technology, solid resin is used as catalyst, the combination technique of reaction and distillation is developed, and then yield and quality are greatly improved. With the help of methylal plant, general-concentration methylal is processed into low-concentration methylal, 92% methylal is pressed into the differential pressure distillation column for pressure distillation. Pressure is controlled at 1.2-1.5Mpa, the top temperature of the distillation column is controlled at 120 ℃, and the bottom temperature of the distillation column is controlled at 135 ℃. High concentration methylal is produced at the bottom, distillate at the top of column flow back to the reaction column and thepressure distillation column.
The combination of methylal physical properties such as low molecular weight, minimal viscosity and high solvent power make methylal an ideal candidate for application in environmentally friendly paint strippers.
How far does methanol-formaldehyde-methylal chain can go?
The methylal technology is produced by the condensation reaction of methanol and formaldehyde. The operation of a huge amount of methylal devices brings more space for methanol demands. The chain of methanol-formaldehyde-methylal looks stable and has good demand support. The demands are increased for methanol and formaldehyde plant enterprises of overcapacity. However, a series of market performance reflects the market space of methylal is very small, and the chain of methanol-formaldehyde-methylal chain will be at the risk of out of control.
Thursday, September 5, 2013
Dimethylformamide
Dimethylformamide
(DMF) is an organic compound that is used as a solvent for many
products, including lacquers, pigments and dyes. Known as a volatile
organic compound (VOC), DMF can endanger both humans and wildlife, but
the threat is regarded as minimal because it does not occur in nature
and isn't encountered by humans outside of occupational settings. Dimethylformamide is not stable when strong acids or bases are around it, and it hydrolyzes back into its original state of dimethylamine and formic acid. According to the Material Safety Data Sheet (MSDS), dimethylformamide is hazardous to health, flammable, reacts to skin on contact and poses a minimal threat of reacting with other chemicals.
Recently we showed how crystallization in microemulsions could lead directly to the most stable polymorph, thereby leapfrogging Ostwald’s rule of stages. Here we consider in more details the crystallization of mefenamic acid from dimethylformamide microemulsions. Crystallization of mefenamic acid from bulk DMF has previously been shown to produce only the metastable Form II irrespective of the supersaturation or temperature.
Dimethylformamide is a polar (hydrophilic) aprotic solvent with a high boiling point. It facilitates reactions that utilizes polar mechanisms, such as SN2 reactions. Dimethylformamide can be synthesized from methyl formate and dimethylamine or by reaction of dimethylamine with carbon monoxide. Dimethylformamide is not stable in the presence of strong bases such as sodium hydroxide or strong acids such as hydrochloric acid or sulfuric acid and is hydrolyzed back into formic acid and dimethylamine, especially at elevated temperatures.
Recently we showed how crystallization in microemulsions could lead directly to the most stable polymorph, thereby leapfrogging Ostwald’s rule of stages. Here we consider in more details the crystallization of mefenamic acid from dimethylformamide microemulsions. Crystallization of mefenamic acid from bulk DMF has previously been shown to produce only the metastable Form II irrespective of the supersaturation or temperature.
Dimethylformamide is a polar (hydrophilic) aprotic solvent with a high boiling point. It facilitates reactions that utilizes polar mechanisms, such as SN2 reactions. Dimethylformamide can be synthesized from methyl formate and dimethylamine or by reaction of dimethylamine with carbon monoxide. Dimethylformamide is not stable in the presence of strong bases such as sodium hydroxide or strong acids such as hydrochloric acid or sulfuric acid and is hydrolyzed back into formic acid and dimethylamine, especially at elevated temperatures.
There are several ways to form dimethylformamide,
all of which involve the use of dimethylamine. For smaller production
runs, dimethylamine is catalyzed with carbon monoxide and methanol or
with methyl formate. In larger, laboratory-scale productions, formic
acid and dimethylamine react together to create this solvent.
In contrast, we show that stable Form I can be produced from DMF microemulsions provided the lowest supersaturations that can achieve crystallization are used; these correspond to initial supersaturations that are significantly higher than those commonly used in bulk solution crystallizations, owing to the large decrease in supersaturation that occurs when a nuclei grows in a 3D-nanoconfined droplet. Increasing the supersaturation above the minimum required for crystallization leads to increasing proportions of metastable Form II crystals.
In contrast, we show that stable Form I can be produced from DMF microemulsions provided the lowest supersaturations that can achieve crystallization are used; these correspond to initial supersaturations that are significantly higher than those commonly used in bulk solution crystallizations, owing to the large decrease in supersaturation that occurs when a nuclei grows in a 3D-nanoconfined droplet. Increasing the supersaturation above the minimum required for crystallization leads to increasing proportions of metastable Form II crystals.
As a solvent, or a chemical that mixes with other liquids, dimethylformamide
is used in the formation of many products that require a strong
chemical reaction. Its high boiling point leaves it with low evaporation
potential, so it will not quickly dissipate when used with other
chemicals at high temperatures. Many plastics and curing processes, such
as the curing done to leather, need this chemical to complete the
product or process. It also can be used to break down many organic
compounds.
Dimethylformamide
is a neutral compound, so it does not react very well when paired with a
strong acid or base. A strong base would be a compound such as sodium
hydroxide, and a strong acid would be something such as sulfuric acid.
When a base or acid is paired with this compound, it will revert to its
two original components. This reverting process is increased if placed
in a high-temperature vat.
Co-exposure of noise, DMF and TOL can affect the ambulatory blood pressure and heart rate among synthetic leather workers. Noise exposure may have obviously higher effect than chemical exposure.
Co-exposure of noise, DMF and TOL can affect the ambulatory blood pressure and heart rate among synthetic leather workers. Noise exposure may have obviously higher effect than chemical exposure.
Dimethylformamide
is a VOC, meaning it is dangerous for humans and wildlife. It is not
made in nature and isn't encountered outside certain work settings, so
it is not regarded as an especially hazardous compound. Testing has
shown that DMF can easily and quickly transfer from dirt to groundwater
and will quickly spread through any body of water. Dimethylformamide also has been shown to cause cancer and chronically affect organs such as the lungs and heart.
The
MSDS, which grades all compounds on a scale of 0 to 4 with 4 being a
serious hazard, shows DMF to be a hazard. The worst risk is contacting
or touching the chemical, which is rated as a 3. Both health and
flammability risks earn a 2; DMF also must be stored away from high
temperatures. The reactivity level is only 1, so it should not react
with other compounds in an adverse way.This article is from http://www.hiseachem.com/news/Dimethylformamide.htm .
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