Volatility kerosene

Volatilization from mixtures of organic contaminants brings about changes in both the physical and the chemical properties of the residual liquid. We consider data on kerosene volatilization, as summarized in Yaron et al. (1998). Kerosene is an industrial petroleum product composed of more than 100 hydrocarbons, which may become a subsurface contaminant. 

In the subsurface, kerosene volatilization is controlled by the physical and chemical properties of the solid phase and by the water content. Porosity is a major factor in defining the volatilization process. Galin et al. (1990) reported an experiment where neat kerosene at the saturation retention value was recovered from coarse, medium, and fine sands after 1, 5, and 14 days of incubation. The porosity of the sands decreased from coarse to fine. Figure 8.9 presents gas chromatographs obtained after kerosene volatilization. Note the loss of the more volatile hydrocarbons by evaporation in all sands 14 days after application and the lack of resemblance to the original kerosene. It is clear that the pore size of the sands affected the chemical composition of the remaining kerosene. For example, the fractions disap-... 

The effect of aggregation of the subsurface solid phase on kerosene volatilization was studied by Fine and Yaron (1993), who compared the rate of aggregation in two size fractions of a vertisol soil the <1 mm fraction and 2 mm aggregates. The total porosity of these two fractions was similar (53% and 55% of the total volume, respectively). Differences in aggregation are reflected in the air permeability that is, their respective values were 0.0812 0.009 cm and 0.145 0.011 cm Figure 8.10 presents the volatilization of kerosene as affected by the soil aggregation, when the initial amount applied was equivalent to the retention capacity. The more permeable fraction releases kerosene faster and thus enhances volatilization. 

These examples indicate that aggregation and pore-size distribution parameters affect volatilization of petroleum products from a contaminated subsurface. Fine and Yaron (1993) report that kerosene volatilization depends on the type of soil. Tests on four soils with a clay content increasing from 0.3% to 74.4%, and organic matter... 

Microorganisms readily able to degrade hydrocarbons were found in the Neuse River estuary in North Carolina. Although the estuary was relatively free of hydrocarbon contamination, 63% of the bacteria and 71% of the fungi isolated from surface water samples were able to utilize kerosene as the sole carbon source (Buckley et al. 1976). Weathered kerosene (volatile components were allowed to escape prior to testing) was spiked with four marker hydrocarbons, and the degradation of the markers was monitored. 

The products could be classified as a function of various criteria physical properties (in particular, volatility), the way they are created (primary distillation or conversion). Nevertheless, the classification most relevant to this discussion is linked to the end product use LPG, premium gasoline, kerosene and diesel oil, medium and heavy fuels, specialty products like solvents, lubricants, and asphalts. Indeed, the product specifications are generally related to the end use. Traditionally, they have to do with specific properties octane number for premium gasoline, cetane number for diesel oil as well as overall physical properties such as density, distillation curves and viscosity. 

Strontium is softer than calcium and decomposes in water more vigorously. It does not absorb nitrogen below 380oC. It should be kept under kerosene to prevent oxidation. Freshly cut strontium has a silvery appearance, but rapidly turns a yellowish color with the formation of the oxide. The finely divided metal ignites spontaneously in air. Volatile strontium salts impart a beautiful crimson color to flames, and these salts are used in pyrotechnics and in the production of flares. Natural strontium is a mixture of four stable isotopes. 

Petroleum Oils. When satisfactorily stable kerosene—soap—water emulsions were produced in 1874, dormant (winter) oil sprays became widely used to control scale insects and mites (1). The first commercial emulsion or miscible oil was marketed in 1904 and by 1930 highly refined neutral or white oils, free from unsaturated hydrocarbons, acids, and highly volatile elements, were found to be safe when appHed to plant foHage, thus gready enlarging the area of usefulness of oil sprays (see Petroleum). 

Emulsives are solutions of toxicant in water-immiscible organic solvents, commonly at 15 ndash 50%, with a few percent of surface-active agent to promote emulsification, wetting, and spreading. The choice of solvent is predicated upon solvency, safety to plants and animals, volatility, flammabiUty, compatibihty, odor, and cost. The most commonly used solvents are kerosene, xylenes and related petroleum fractions, methyl isobutyl ketone, and amyl acetate. Water emulsion sprays from such emulsive concentrates are widely used in plant protection and for household insect control. 

Some hquid defoamers are preemulsified relatives of paste defoamers. In addition to the fatty components mentioned above, kerosene [8008-20-6] or an organic cosolvent such as 2-propanol have been used to enhance stabiUty of the oil—water emulsion and the solubiUty of the defoamer s active ingredients. These cosolvents are used less frequently as concerns increase about volatile organic emissions (VOCs) from the paper machine. Additionally, the use of ultrapure mineral oil in defoamers has become commonplace. Concern about the creation of 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and 2,3,7,8-tetrachlorodibenzofuran (TCDF) in the pulping process has led to the discovery of unchlorinated precursor molecules, especially in recycled mineral oil and other organic cosolvents used in defoamer formulations (28). In 1995 the mineral oil that is used is essentially free of dibenzodioxin and dibenzofuran. In addition, owing to both the concern about these oils and the fluctuating cost of raw materials, the trend in paper machine defoamers is toward water-based defoamers (29). 

Liquid fuels for ground-based gas turbines are best defined today by ASTM Specification D2880. Table 4 Hsts the detailed requirements for five grades which cover the volatility range from naphtha to residual fuel. The grades differ primarily in basic properties related to volatility eg, distillation, flash point, and density of No. 1 GT and No. 2 GT fuels correspond to similar properties of kerosene and diesel fuel respectively. These properties are not limited for No. 0 GT fuel, which allows naphthas and wide-cut distillates. For heavier fuels. No. 3 GT and No. 4 GT, the properties that must be limited are viscosity and trace metals. 

A minimum volatihty is frequently specified to assure adequate vaporization under low temperature conditions. It can be defined either by a vapor pressure measurement or by initial distillation temperature limits. Vaporization promotes engine start-up. Fuel vapor pressure assumes an important role particularly at low temperature. For example, if fuel has cooled to —40°C, as at arctic bases, the amount of vapor produced is well below the lean flammabihty limit. In this case a spark igniter must vaporize enough fuel droplets to initiate combustion. Start-up under the extreme temperature conditions of the arctic is a major constraint in converting the Air Force from volatile JP-4 to kerosene-type JP-8, the military counterpart of commercial Jet Al. 

Vaporized fuel oil gas behaves very elosely to natural gas beeause it provides high performanee with a minimum reduetion of eomponent life. About 40% of the turbine power installed operates on liquid fuels. Liquid fuels ean vary from light volatile naphtha through kerosene to the heavy viseous residuals. The elasses of liquid fuels and their requirements are shown in Table 12-1. 

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). 

Middle Distillates Lower volatility distillates including diesel fuel, kerosene, jet fuels, and lighter fuel oils. 

Other important properties include Hash point, volatility, viscosity, specific gravity, cloud point, pour point, and smoke point. Most of these properties are related directly to the boiling range of the kerosene and are not independently variable. The flash point, an index of fire hazard, measures the readiness of a fuel to ignite when exposed to a flame. It is usually mandated by law or government regulation to be 120° or 130° F (48° or 72° C), Volatility, as measured... 

Diesel-like products (jet fuel, diesel. No. 2 fuel oil, kerosene) are moderately volatile products that can evaporate with no residue. They have a low-to-moderate viscosity, spread rapidly into thin slicks, and form stable emulsions. They have a moderate-to-high (usually, high) toxicity to biota, and the specific toxicity is often related to type and concentration of aromatic compounds. They have the ability to penetrate substrate, but fresh (unoxidized) spills are nonadhesive. 

The differential volatilization of neat kerosene components from a liquid phase, directly into the atmosphere during volatilization up to 50% (w/w), is presented in Fig. 8.8. Ten kerosene components were selected, and their composition was depicted as a function of gas chromatograph peak size (%), which is linearly related to their concentration. It may be seen that the lighter fractions evaporate at the beginning of the volatilization process. Increasing evaporation causes additional components to volatilize, which leads to a relative increase in the heavier fractions of kerosene in the remaining liquid. 

Fig. 8.8 Major remaining components of kerosene during the volatilization process (Yaron et al. 1998)...

Fig. 8.9 Effect of porosity on composition of kerosene during 14 days of volatilization from fine, medium and coarse sand, as seen from gas chromatograph analyses. Reprinted from Galin Ts, Gerstl Z, Yaron B (1990) Soil pollution by petroleum products. IB Kerosene stability in soil columns as affected by volatilization. J Contam Hydrol 5 375-385. Copyright 1990 with permission of Elsevier...

Fig. 8.10 Volatilization of kerosene from vertisol as affected by aggregate size. Reprinted from Fine P, Yaron B (1993) Outdoor experiments on enhanced volatilization by venting of kerosene components from soil. J Contam Hydrol 12 335-374. Copyright 1994 with permission of Elsevier...

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