Uses of tetraethyl lead, hazards, storage and waste disposal

Uses of tetraethyl lead, hazards, storage and waste disposal by David Pritchard

Until recently Tetra Ethyl-Lead or TEL was a popular additive to petrol. TEL was added to petrol to improve the octane rating of petrol. TEL is a non biodegradable substance that easily dissolves in petrol and reduces ‘knocking’ in the engine. Not only does TEL allow a higher compression ratio in engines, it also improves the efficiency of engines. TEL was first used as an additive in the US in the 1920s. The effectiveness of TEL as an additive was discovered way back in 1921, what is interesting to note is that TEL was so toxic nearly a dozen researches died while experimenting with TEL.

Despite its known toxicity, Exxon and GM (General Motors) created the Ethyl Petrol Corporation to manufacture and market TEL (the year was 1924). What is shocking is that when the EPA finally started proceedings to phase out TEL in 1974, they were sued by the Ethyl Petrol Corporation. It was only when the EPA won the law suit that the phasing out of TEL began. In fact, the European Union was even slower to react, and only in the year 2000 was TEL completely phased out as an additive to petrol by the European Union.

The reason why TEL has been ‘phased out’, is that on combustion TEL forms Lead Oxide. The Lead Oxide then reacts with Ethylene Dibromide (another petrol additive). Then end result of TEL combustion is Lead Bromide a highly volatile and toxic gas. Lead Bromide not only causes air pollution, but it also leaches into the soil surrounding highways and roads. In addition, the lead in TEL damages catalytic converters that have been standard equipment for US cars for many years now. Whatever the reasons for phasing out TEL, TEL is a highly toxic substance and TEL has posed a serious environment and health risk over the years.

TEL free petrol is now available all over the world, as of today only a handful of countries actually sell leaded petrol (the term ‘leaded’ indicates the petrol still has TEL). Even though TEL has been eradicated as an additive, even today the concentration of lead in soil surrounding roadways is very high. Aviation fuel and high performance fuel still have TEL. In fact, there has been no suitable replacement for TEL in aviation fuel and every year a small amount of TEL is still produced to be added to aviation fuel. Similarly, TEL is also a standard additive in high octane fuel for racing.

As of 2007, unleaded petrol is available throughout the world, and the only countries in which leaded petrol is extensively used are Yemen, Afghanistan and North Korea. Leaded petrol is still available in parts of Northwest Africa, Europe, Commonwealth of Independent States (CIS), Iraq, Jordan and the Palestinian territories. The use of alternative additives and high quality petrol has meant that slowly but surely the phasing out of TEL as an additive in petrol has been a success, however more work needs to be done to completely eliminate TEL from all type of fuels.

Bradley Abert is the author of this article on tetraethyl lead.
Find more information about tetraethyl lead tank remediationhere.

Article Source: Sustainable Living Articles

Folic Acid Formula and Chemistry

Folic Acid Formula and Chemistry by hari

Folic acid is a water soluble vitamin that is associated with the B vitamins. Originally all of the B vitamins were thought to be the same vitamin until it was discovered that they were actually a complex of vitamins that occurred in the same foods and in many cases worked together in the body .



Folic acid is also referred to as folate, folacin or sometimes vitamin M. Folate is basically used to describe the derivatives of a compound called, pteroylglutamic acid. This is the most commonly sold type of folate in the supplement industry. In the industry, folic acid is a term used to pteroylglutamic acid and the term folate is used to imply the derivatives of pteroylglutamic acid.



In fact the food we eat from the natural world contains mostly folates and not folic acid. Folates can be found in liver, yeast, green leafy veggies, peas, and some fruits including citrus.



The form used in fortifying foods is pteroylglutamic acid (PGA) or folic acid itself. Today the government requires fortification of certain foods with folic acid because it is so important to the human body. Mostly folic acid is fortified in cereals and flours. Folic acid can also be found by itself as a supplement or in a B vitamin complex.



Pteroylglutamic acid (PGA) is composed of three large subunits. These are pteridine, P-amino benzoic acid, and glutamic acid. As is easy to see PGA takes its name from combination of the names of the three subunits. Glutamic acid is an amino acid that the body can actually synthesize by itself and is found in proteins.



Folate and folic acid once absorbed are carried to the liver via the bloodstream. Here a small portion of aproximantly a tenth of a mg/day is excreted into the bile. Bile is used by the body to help breakdown fats for absorption, so the folic acid is reabsorbed by the body in this process. Over the course of the day the liver is the main storage site for folic acid containing half of the body’s folic acid supply.



Folic acid found in the cell’s cytoplasm in the form 5-methyl-THF-monoglutamate. In order for folic acid in the blood to be taken into the bodies cells it must first be converted to 5-methyl-THF-monoglutamate from 5-methyl-THF via an enzymatic reaction using vitamin B12. This is an example of the B vitamins working together in the body.



On average the body doesn’t store folic acid or folates long-term and they need to be taken in daily. Interestingly the synthetic form of folic acid sold in supplements and in fortified foods is easier for the human body to absorb than the natural form. In order to get the same amount of nutrient from natural foods as you do from synthetic supplement a person would need to take in one mcg. of folate for every .6 mcg. of folic acid.



The average adult should take in about four hundred micrograms of folic acid daily. Those pregnant, who could become pregnant, or are lactating should take between six hundred and eight hundred micrograms daily.



Author Vincent Platania represents the Stanley Home Products. Stanley Home Products has been in business since 1936, and offers high quality home and personal care products to keep your home and your body clean.
Visit http://www.stanleybeautycare.com




Article Source: Sustainable Living Articles

Folic Acid Formula and Chemistry

Folic Acid Formula and Chemistry by hari

Folic acid is a water soluble vitamin that is associated with the B vitamins. Originally all of the B vitamins were thought to be the same vitamin until it was discovered that they were actually a complex of vitamins that occurred in the same foods and in many cases worked together in the body .



Folic acid is also referred to as folate, folacin or sometimes vitamin M. Folate is basically used to describe the derivatives of a compound called, pteroylglutamic acid. This is the most commonly sold type of folate in the supplement industry. In the industry, folic acid is a term used to pteroylglutamic acid and the term folate is used to imply the derivatives of pteroylglutamic acid.



In fact the food we eat from the natural world contains mostly folates and not folic acid. Folates can be found in liver, yeast, green leafy veggies, peas, and some fruits including citrus.



The form used in fortifying foods is pteroylglutamic acid (PGA) or folic acid itself. Today the government requires fortification of certain foods with folic acid because it is so important to the human body. Mostly folic acid is fortified in cereals and flours. Folic acid can also be found by itself as a supplement or in a B vitamin complex.



Pteroylglutamic acid (PGA) is composed of three large subunits. These are pteridine, P-amino benzoic acid, and glutamic acid. As is easy to see PGA takes its name from combination of the names of the three subunits. Glutamic acid is an amino acid that the body can actually synthesize by itself and is found in proteins.



Folate and folic acid once absorbed are carried to the liver via the bloodstream. Here a small portion of aproximantly a tenth of a mg/day is excreted into the bile. Bile is used by the body to help breakdown fats for absorption, so the folic acid is reabsorbed by the body in this process. Over the course of the day the liver is the main storage site for folic acid containing half of the body’s folic acid supply.



Folic acid found in the cell’s cytoplasm in the form 5-methyl-THF-monoglutamate. In order for folic acid in the blood to be taken into the bodies cells it must first be converted to 5-methyl-THF-monoglutamate from 5-methyl-THF via an enzymatic reaction using vitamin B12. This is an example of the B vitamins working together in the body.



On average the body doesn’t store folic acid or folates long-term and they need to be taken in daily. Interestingly the synthetic form of folic acid sold in supplements and in fortified foods is easier for the human body to absorb than the natural form. In order to get the same amount of nutrient from natural foods as you do from synthetic supplement a person would need to take in one mcg. of folate for every .6 mcg. of folic acid.



The average adult should take in about four hundred micrograms of folic acid daily. Those pregnant, who could become pregnant, or are lactating should take between six hundred and eight hundred micrograms daily.



Author Vincent Platania represents the Stanley Home Products. Stanley Home Products has been in business since 1936, and offers high quality home and personal care products to keep your home and your body clean.
Visit http://www.stanleybeautycare.com




Article Source: Sustainable Living Articles

The Use of Fluorochemical Compounds in Organic Chemistry

The Use of Fluorochemical Compounds in Organic Chemistry by Craig Elliott

Generally, the major uses of fluorochemical compounds fall into three major categories at the turn of the 21st century. The first are the rather stable halocarbon compounds used in medicine such as several types of inhalation anesthetics for anaesthesia. A very major industrial use is in the form of heat tolerant and inert synthetic oils and metalworking lubricants. However, there are many fluorochemicals and halocarbon chemicals that are used extensively, albeit carefully, in organic (meaning carbon containing) chemistry. The unique nature of fluorine, even among other halogen elements, grants halocarbon fluoro compounds unique properties that are indispensable in organic chemical work.



Since the discovery of hydrofluoric acid (HF) from calcium fluoride and sulphuric acid in the 17th century, it has been well known to generations of chemists that certain fluorochemical compounds have very unusual properties. The etching of glass has been performed commercially with HF since the 18th century. Despite being a weak acid, it has an unparalleled ability to corrode silicon and calcium. Much of the pure and quite toxic elemental fluorine (F) is produced from HF by electrolysis.



Trifluoroacetic Acid (TFA) is another very commonly used halocarbon compound. TFA is a relatively simple organic molecule and is a colorless liquid that is a powerful carboxylic acid in solution. It can be produced by "electro-fluorinating" plain old acetic acid. Though similar to the much more familiar acetic acid (better known as the business end of vinegar), it is a strong acid in this form, stronger than acetic acid by at least 3 orders of magnitude.



On the other hand, Trifluoroacetic Anhydride (TFAA) is a very similar substance that is often used in creating free trifluoro methyl groups in organic reactions. It is a handy relative to TFA that can be stored indefinitely as long as it doesn't get wet. When it does come in contact with water it reverts back to TFA. It can be made by chemically dehydrating TFA. However, TFAA is also very highly corrosive, and dangerous to work with under anything but the strictest of conditions. Even just inhaling fumes from a TFAA reaction can cause permanent lung injury, as many reactive fluorochemicals do in their gaseous state.



The use of 2,2,2-Trifluoroethanol (TFE), sometimes known by its old school name trifluoroethyl alcohol, in organic chemistry for many years has been to dissolve nylon. A colourless liquid that smells like everyday ethanol, trifluoroethanol is very often used as a solvent since it is more acidic than water given the highly negative nature of the fluorine end of the molecule. This characteristic also makes it possible for useful hydrogen bridging to occur in solution, making it a useful intermediary step in the creation of more stable and non-toxic fluorochemical compounds with heterocycles such as the amino acid pyridine.



More recently, TFE has been used as part of a solvent capable of selectively cleaving bits of folded proteins off their parent molecule. TFE is also notable for being the source of trifluoroacetaldehyde and TFA when oxidized. Though TFE doesn't reach a gaseous state until temperatures exceed 70C, the liquid has a flash point of only 33C. Controlled lab conditions are absolutely necessary when handling TFE.



Trifluoroacetyl Chloride (or TFAC) is perhaps the most difficult of these to work with. It is a gas at room temperature (down to below the freezing point of water) and one that doesn't smell very good, at that. TFAC is almost always delivered to labs and vendors in pressurized cylinders that are handled very carefully since the contents are toxic and acidic when released into the air. Contact with the skin is not recommended under any circumstances, since the contents will readily hydrolyze into TFA and hydrochloric acid.



TFAC is highly advantageous when used as an intermediate substance in the synthesis of organic molecules. Pesticides and herbicides also use TFAC in the manufacturing process.



Though fluorochemical compounds are very often dangerous or toxic themselves, they very strongly bond to many organic molecules and provide the properties that make many of the wonders of modern medicine possible. That said, research into testing the stability of the novel halocarbon compounds that are introduced every year continues in the interest of public health.



Any client who wishes to utilize halocarbon chemicals in a lab or manufacturing capacity is advised to make themselves fully aware of the MSDS data sheet for each fluoro-chemical since so many of them are corrosive in their native state and some are even explosive when improperly handled. It is of the highest and utmost importance to use care and consider safety first when using fluorochemicals in any environment.



About Author:

Craig Elliott is a writer for halocarbon.com. Halocarbon.com is a leading provider of Fluorochemicals | Anesthetics



Article Source: Sustainable Living Articles

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