Flash point ethanol

The classes of solvents which are most favourable. Table 16.2 Diluted ethanol flash point ... 

Like brines, alcohols were readily available and widely used as antifreeze Hquids in the early 1900s. Both methanol and ethanol offer exceUent heat transfer and efficient freeze point depression. However, the alcohols have the distinct disadvantage of their low boiling points. During the summer months when the engines operate hot, significant amounts of the alcohols are lost because of evaporation. These evaporative losses result in cosdy make-up requirements. Additionally, the alcohols have very low flash points and potentially flammable vapors. These safety concerns have, particularly in recent years, caused the use of alcohols to be completely discontinued for most heat-transfer systems. 

The partial pressure of LEL ethanol is 0.0327 atm. The temperature that produces a vapor pressure of 0.0327 atm is I l C. which is our predicted flash point. This is close to the reported 13°C. 

The most widely known aleohol is ethyl aleohol, simply beeause it is the aleohol in aleoholie drinks. It is also known as grain aleohol, or by its proper name, ethanol. Ethyl aleohol is a eolorless, volatile liquid with a eharaeteristie odor and a pungent taste. It has a flash point of 55°F, is classified as a depressant drug, and is toxic when ingested in large quantities. Its molecular formula is CjHjOH. In addition to its presence in alcoholic beverages, ethyl alcohol has many industrial and medical uses, such as a solvent in many manufacturing processes, as antifreeze, antiseptics, and cosmetics. 

Some organic compounds can be in solution with water and the mixture may still be a flammable mixture. The vapors above these mixtures such as ethanol, methanol, or acetone can form flammable mixtures with air. Bodurtha [39] and Albaugh and Pratt [47] discuss the use of Raoult s law (activity coefficients) in evaluating the effects. Figures 7-52A and B illustrate the vapor-liquid data for ethyl alcohol and the flash point of various concentrations, the shaded area of flammability limits, and the UEL. Note that some of the plots are calculated and bear experimental data verification. 

Alcohols such as methanol and ethanol are readily available and are occasionally used despite significant disadvantages, such as low boiling points. During summer months significant amounts of alcohol can be lost due to evaporation. Such losses lead to costly replacement of the additive. Furthermore, alcohols have low flash points, which may cause safety problems. Moreover, methanol is highly poisonous. Therefore, the use of alcohols has ceased almost completely in recent years. 

Solubility Slightly soluble in water (152 mg/L at 20 °C) (ECETOC, 1986) and chloroform miscible with diethyl ether and ethanol (Lide Milne, 1996) (g) Volatility Vapour pressure, 1.28 kPa at 25 °C (Lide Milne, 1996) relative vapour density (air = 1), 3.7 (Verschueren, 1996) flash-point (closed-cup), 15 °C (Coty et al., 1987)... 

Flash point (+) 36°C (-) 34°C Soluble in ether, hydrocarbons, chloroform, benzene, ethanol etc. ... 

Acetone is very flammable and should not be exposed to heat or flame. Mixts of acet vapor with air are expl if the acet content is 2.55 to 12.8% at RT. The ignition temp of acet vapor in air at 0° is 567° and in oxygen 485° (Ref 20). The expl props and hazards of acet air mixts and precautions against their propagation to expln are discussed in Refs 5,6,7,8,9,19,27 28. The expel detmn of weak shocks in liqs, such as acet, ethanol and ether is discussed in Ref 45. Brooke (Ref 40) detmnd the flash points of acet-water mixts and has shown that they are ignitable even when the acet content is as low as 2%. The fl p of a 2% acet-water mixt is 44.4° and of an 18% soln is 7.1°. The fl p decreases rapidly with an increase in the acet content. In pouring acet down the drain, it is ad visible to add enough water to make the acet concn less than 2%... 

It is safer than ethanol because of its higher flash point and lower vapor pressure. 

Butanol (h-butanol boiling point 117.7°C, density 0.8097, flash point 28.9°C) can be obtained from carbohydrates (such as molasses and grain) by fermentation. Acetone and ethanol are produced as by-products. 

A flammable chemical substance is a solid, liquid, vapor, or gas that ignites easily and burns rapidly in air. Many of the flammable chemicals used in laboratories are flammable liquids and organic solvents. The vapors of these chemical substances form ignitable mixtures with air. Based on the flash points of these chemicals, classifications are made. The flash point of a chemical substance is defined as the lowest temperature at which a fuel-air mixture present above the surface of a liquid will ignite, if an ignition source is present. The common flammable chemical substances include, but are not restricted to, acetone, benzene, cyclohexane, ethanol, ethyl acetate, ethyl ether, gasoline, hexane, isopropyl alcohol, methanol, propanol, tetrahydro-furan and toluene, and xylene. 

Diethyl ether (bp 35°) is the most commonly used solvent in spite of its low boiling point, low flash point, and ease of forming peroxides, a property shared by all ethers. For extracting aqueous solutions, U.S.P. ether, which contains a few per cent of alcohol and water, is usually quire satisfactory. However, for most reactions, anhydrous ether is required. The U.S.P. ether may be fairly well dried by heating to reflux with sodium wire overnight. Ether purified in this fashion is also useful in extracting compounds which have a boiling point close to that of ethanol or which may react with ethanol, since this is present in the U.S.P. ether. It may be noted that anhydrous ether is also commercially available. 

Dimethyl phthalate is sensitive to prolonged exposure to light and it should therefore be stored in a cool, dark, dry, well-ventilated area that is protected from physical damage, and isolated from incompatible substances. Containers of dimethyl phthalate may be hazardous when empty as they may retain product residues such as vapors and liquids. There is a slight fire hazard when exposed to heat, and above the flash point (see Section 10) explosive vapor-air mixtures may be formed. Carbon dioxide and carbon monoxide are released when dimethyl phthalate is heated to decomposition. Solutions of dimethyl phthalate in acetone, dimethyl sulfoxide, ethanol... 

Neither the handkerchief nor the banknote have suffered any damage, because only the alcohol burns. The flame has the characteristic yellow color of sodium. The boiling point of ethanol is 78 C, while its flash point is 12 °C. 

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