Gasoline flash point

The process fluid. Cyclohexane (CgHi2, MW 84) is a colorless liquid similar in some of its properties to gasoline (flash point 20°C, auto-ignition temperature (AIT) 245°C). The fluid has a normal boiling point of 80°C and a saturation pressure, p i, at 150°C of 0.55 MPa. When the liquid was saturated with nitrogen, or air as when oxidation was occurring in the reactor stream, the pressure was 0.96 MPa. Under these conditions the liquid was 99.8% CsHi2 and 0.2% Nj or air the vapor would have consisted of 82.6% C Hij and 17.4% Nj... 

It should be noted finally that adding gasoline to diesel fuel which was sometimes recommended in the past to improve cold behavior conflicts with the flash point specifications and presents a serious safety problem owing to the presence of a flammable mixture in the fuel tank airspace. Adding a kerosene that begins to boil at 150°C does not have the Scune disadvantage from this point of view. 

Small concentrations of volatile components in a liquid mixture may accumulate in the vapor space of a container over time and appreciably reduce the flash point relative to the reported closed-cup value. This may be the result of degassing, chemical reaction or other mechanism. An example is bitumen [162]. Similarly, if a tank truck is not cleaned between deliveries of gasoline and a high flash point liquid such as kerosene or diesel oil, the mixture might generate a flammable atmosphere both in the tmck tank and the receiving tank. Contamination at the thousand ppm level may create hazards (5-1.4.3 and 5-2.5.4). Solids containing upward of about 0.2 wt% flammable solvent need to be evaluated for flammable vapor formation in containers (6-1.3.2). 

Nature produces a tremendous amount of methyl aleohol, simply by the fermentation of wood, grass, and other materials made to some degree of eellulose. In faet, methyl aleohol is known as wood aleohol, along with names sueh as wood spirits and methanol (its proper name the proper names of all aleohols end in -ol). Methyl aleohol is a eolorless liquid with a eharaeteristie aleohol odor. It has a flash point of 54°F, and is highly toxie. It has too many eommereial uses to list here, but among them are as a denaturant for ethyl alcohol (the addition of the toxie ehemieal methyl aleohol to ethyl aleohol in order to form denatured aleohol), antifreezes, gasoline additives, and solvents. No further substitution of hydroxyl radieals is performed on methyl aleohol. 

This term is used to describe oils that have a flash point above ambient temperature. They will therefore not burn or explode at ambient temperature but will do so when hot. Unfortunately many people do not realize this and treat heavy oils with a disrespect that they would never apply to gasoline, as shown by the incidents described below. Another incident was described in Section 12.2 (c). Heavy oils are widely used as fuel oils, solvents, lubricants, and heat transfer oils, as well as process materials. 

The flash-point is a measure of the ease of ignition of the liquid. It is the lowest temperature at which the material will ignite from an open flame. The flash-point is a function of the vapour pressure and the flammability limits of the material. It is measured in standard apparatus, following standard procedures (BS 2000). Both open- and closed-cup apparatus is used. Closed-cup flash-points are lower than open cup, and the type of apparatus used should be stated clearly when reporting measurements. Flash-points are given in Sax s handbook, Lewis (2004). The flash-points of many volatile materials are below normal ambient temperature for example, ether —45°C, petrol (gasoline) —43°C (open cup). 

Samples from the same study averaged over a typical 8-hour workshift for the area around the backhoe showed average levels of 3.06 mg/m3 (1.10 ppmv). Even higher levels (perhaps in excess of 10,000 ppmv) are possible around large spills of -hexane at such elevated concentrations, as with many components of gasoline-type hydrocarbons, there could be considerable danger from explosions, which are possible when the -hexane levels exceed approximately 1.2% of the volume of air (Merck 1989). Since 0.1% by volume is equivalent to 1,000 ppmv, this flash-point level for -hexane would be at a level of 12,000 ppmv or higher. 

The flash point of a petroleum product is also used to detect contamination. A substantially lower flash point than expected for a product is a reliable indicator that a product has become contaminated with a more volatile product, such as gasoline. The flash point is also an aid in establishing the identity of a particular petroleum product. 

Liquids with flash points below Gasoline, naphtha, benzol, and similar 55... 

Physical Form. JP-4 is a colorless to straw-colored liquid with the odor of gasoline and/or kerosene. JP-7 is a liquid, usually colorless and with the odor of kerosene. JP-4 can be made by refining either crude petroleum oil or shale oil. It is called a wide cut fuel because it is produced from a broad distillation temperature range and contains a wide array of carbon chain lengths, from 4- to 16. It consists of approximately 13% (v/v) aromatic hydrocarbons, 1.0% olefins, and 86% saturated hydrocarbons. JP-7 is made by refining kerosene, a product of refined crude petroleum. It was developed for use in advanced supersonic jets because of its thermal stability and high flash point. ... 

It Ls important to note that a combustible liquid at or above its flash point will behave in the same manner that a flammable liquid would in a similar emergency. As an example No.2 fuel oil when heated to a temperature of 150°F can be expected to act or react in the same way gasoline would at 50°F. In most instances, however, to reach this elevated temperature will require the introduction of an external heat source. Some common examples of combustible petroleum liquids are given in Table 7. 

Gas A state of matter defined as a fluid with a vapor pressure exceeding 40 psia at 100° F. Gasolines Mixture of volatile, flammable liquid hydrocarbons used in internal combustion engines. Typical flash point temperature is around -40 °C. 

Gasoline Blending Stocks Alkylates — Fire Hazards Flash Point (deg. F) < 0 CC ... 

Also according to Van Dolah ammonium nitrate-oil mixtures offer a certain dust explosion hazard and any electric equipment (switches controls, motors, lights) located in the plant should conform to the safety requirements or should be installed outside the plant. In order not to increase the dust explosion hazard no liquid hydrocarbon fuel with higher volatility than No. 2 Diesel fuel (minimum flash point of 145°F, ASTM closed-cup procedure) should be used as an admixture to ammonium nitrate. More volatile fuels, such as gasoline, kerosine or No. 1 Diesel fuel cannot be recommended according to Van Dolah, as they would seriously increase the hazard of a vapour explosion. 

The flash point of methane is very low compared to gasoline, though it is hardly a practical consideration since it is very difficult to conceive of situations where pools of liquid methane would exist. 

Methyl tertiary butyl ether (methyl-r-butyl ether, MTBE boiling point 55°C, flash point -30°C) has excited considerable interest because it is a good octane enhancer for gasoline (it blends as if it had a research octane number of 115 to 135). It also offers a method of selectively removing isobutylene from a mixed C4 stream, thus enabling the recovery of high-purity butene-1. Furthermore, methyl tertiary butyl ether can be isolated, then cracked to yield highly pure iso-butylene and methanol. 

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