Antifreeze from ethylene glycol

Antifreeze. Any compound or mixture that lowers the freeing point of water can be referred to as antifreeze. The preponderant, commercial antifreeze is ethylene glycol diluted with water. Other organic compounds used occasionally are methanol, ethanol, and propylene glycol. The primary application is to protect automotive cooling systems from freezing. 

In Delaware, this oil (4500 gal/yr) is recycled at the oil refinery at Delaware City 306 Liquid carbon dioxide is being used to take motor oil off of high-density polyethylene containers, so that both can be recycled.307 Safety-Kleen Corp. offers nationwide collection for used oil and antifreeze from cars and other sources.308 Mobile on-site services are also available for removing toxic compounds and acid degradation products from ethylene glycol antifreeze, with addition of new corrosion inhibitors, so that the antifreeze can be reused.309 Organoclays have been used to remove oils from water.310... 

Most tj es of antifreeze used in cars are solutions of ethylene glycol. Every year, thousands of dogs and cats die from ethylene glycol poisoning because they consume improperly stored antifreeze or antifreeze that has leaked out of a radiator. The antifreeze has a somewhat sweet taste, which attracts a curious dog or cat. Young children are also at risk for ethylene glycol poisoning. 

It is also possible for chemicals to become more toxic when metabolized. A good example of this is ethylene glycol, the major component of antifreeze. When ethylene glycol is ingested it is metabolized to products that accumulate and cause toxic effects, including metabolic acidosis (a condition of excess acid in the body) and severe damage to the kidneys and brain from the formation of crystals of calcium... 

To prevent an engine block from damage by freezing and expansion of the coolant, antifreeze is mixed with water in the cooling system. The chemical name of antifreeze is ethylene glycol, and it has the chemical formula C2H 02. A solution containing 40% ethylene glycol and 60% water by mass freezes at Fahrenheit, or... 

When antifreeze becomes unsuitable for use, either because of depletion of inhibitors, presence of corrosion products or corrosive ions, or degradation of the fluid, recycling and reuse of the antifreeze, rather than disposal, may be considered. Although ethylene glycol is readily biodegraded in typical municipal waste treatment faciHties, antifreeze disposal becomes problematic because the coolant may contain hazardous quantities of heavy metals picked up from the cooling system. Recycling may be economically preferred over coolant disposal and reduces the concern for environmental impact. 

Ethanol has been used in the United States to a considerable extent as an antifreeze but it has largely been replaced for such use by ethylene glycol. The use of fermentation alcohol in automotive fuel has been discussed above. Several tropical countries consider ethanol, produced from regenerable resources, an attractive petrochemical feedstock. 

Aqueous solutions of many salts, of the common strong acids (hydrochloric, nitric and sulphuric), and of bases such as sodium hydroxide and potassium hydroxide are good conductors of electricity, whereas pure water shows only a very poor conducting capability. The above solutes are therefore termed electrolytes. On the other hand, certain solutes, for example ethane-1,2-diol (ethylene glycol) which is used as antifreeze , produce solutions which show a conducting capability only little different from that of water such solutes are referred to as non-electrolytes. Most reactions of analytical importance occurring in aqueous solution involve electrolytes, and it is necessary to consider the nature of such solutions. 

The aquatic toxicity of antifreeze agents is not strictly a function of the main component. Aquatic toxicity may come also from minor components in the formulation. Both ethylene glycol and propylene glycol are believed to be essentially nontoxic for aquatic life. 

Wyandotte A process for making a mixture of ethylene and propylene glycols, for use as antifreeze, from propane. The propane is cracked to a mixture of ethylene and propylene, which are not separated but converted to the corresponding glycols by chlorohydrination. Developed by the Wyandotte Chemicals Corporation. 

Together, antifreeze, PET, and polyester polymers account for about 98% of the ethylene glycol produced in the United States. It is also used sometimes as a deicer for aircraft surfaces. The two hydroxyl groups in the EG molecule also make EG suitable for the manufacture of surfactants and in latex paints. Other applications include hydraulic brake fluid, the manufacture of alkyd resins for surface coatings, and stabilizers for water dispersions of urea-formaldehyde and melamine-formaldehyde The hygroscopic properties (absorbs moisture from the air) make EG useful as a humectant for textile fibers, paper, leather, and adhesives treatment. 

The law of 1906 was only a beginning. It did not regulate the safety and effectiveness of drug formulations. This was no more evident than in the case of mass poisoning which resulted from the consumption of "elixir of sulfanilamide" produced by the S.E. Massengill Company of Bristol, Tennessee. Between September and October 1937 doctors had prescribed almost 12 gallons of a 10% solution of sulfanilamide in an ethylene glycol(antifreeze) solvent flavored with saccharin, caramel, amaranth, and raspberry extract. The company s chief chemist, Harold Watkins, was not aware of the toxicity of that concentration of the solvent. 

Kidney failure from the metabolic formation of calcium oxalate has been especially common in cat species, which have voracious appetites for ethylene glycol in antifreeze. Deposits of solid calcium oxalate have also been observed in the liver and brain tissues of victims of ethylene glycol poisoning. 

Before ethylene glycol [melting point (mp) = — 13°C boiling point (bp) = 199°C] became widely adopted as automobile radiator antifreeze, methanol (bp = 65°C) was used for this purpose. Methanol is less expensive. However, unlike ethylene glycol, it is not an all-season coolant and must he removed from the radiation in hot weather. Explain this difference. 

Alcohols occur widely in nature. Methanol is also known as wood alcohol because it can be obtained by distilling wood in the absence of air. It is very poisonous and can cause blindness or death if ingested. Ethanol is consumed in alcoholic beverages. Other simple alcohols, such as 2-phenylethanol from roses and menthol from peppermint, are constituents of natural flavors and fragrances. Alcohols are important intermediates in chemical synthesis. They are also commonly used as solvents for various chemical processes. Ethylene glycol is used in antifreeze and in the preparation of polymers such as Dacron. 

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