Premium gasoline

The conventional leaded premium gasoline is characterized by minimum RON and MON values of 97 and 86, respectively. In 1993, it was the principal product in the gasoline pool in France having 60% of the sales, but its share is diminishing and, in 2000, it will play mostly a minor role. 

To the refiner, the question of octane numbers in future gasolines is of primary importance because it determines the course of operations, the development or on the contrary the stagnation of such and such a process. Table 5.12 thus gives an example of the typical composition by origin and concentration of different base constituents of three grades of the most common motor fuels distributed today in Europe conventional premium gasoline at 0.15 g Pb/1, Eurosuper and Superplus. 

Specifications and test methods for premium gasoline (see AFNOR information document M ]5-005). 

In relatively small doses (see Chapter 5), additives made it possible for the refiner to gain several points in octane number and thereby to allow the premium gasoline to meet specifications. 

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. 

Chemical composition does not generally come into play, except for the case where it is necessary to establish maximum specifications for undesirable compounds such as sulfur, nitrogen, and metals, or even more unusually, certain compounds or families of compounds such as benzene in premium gasolines. By tradition, the refiner supposedly possesses numerous degrees of freedom to generate products for which the properties but not the composition are specified. 

The most extensive worldwide program on methanol blend gasoline was in Italy where from 1982 to 1987 a 1.9 x lO" m /yr (5 x 10 gal/yr) plant produced a mixture containing 69% methanol. The balance contained higher alcohols. This mixture was blended into gasoline at the 4.3% level and marketed successfully as a premium gasoline known as Super E (82). 

An alternative source of the ethyl component was ethyl bromide, a less expensive material. It was at this point that GM called upon DuPont to take over process development. DuPont was the largest U.S. chemical company at the time. It had extensive experience in the scale-up of complex chemical operations, including explosives and high-pressure synthesis. The manufacturing process was undertaken by DuPont s premier department, the Organic Chemical section. GM contracted with DuPont to build a 1,300 pound per day plant. The first commercial quantities of TEL were sold in Februai-y 1923 in the form of ethyl premium gasoline. 

TEL was not the only way to increase octane number. Those few companies who did not wish to do business with Jersey Standard, sought other means to produce a viable premium gasoline. TEL represented the most serious threat to the traditional gasoline product. It was cheap, vei y effective, and only 0.1 percent of TEL was required to increase the octane number 10 to 15 points. In contrast, between 50 to 100 times this concentration was required of alternative octane enhancers to achieve the same effect. 

A typical gallon of gasoline sells for 3.00 per gallon, with the premium gasoline (Octane Number 93) commanding about a 0.20 premium over the regular gasoline... 

Sea water and corrosion products were delivered with premium gasoline by barge to the fuel distribution terminal storage tanks. The water settled to the bottom of the terminal tank and was drawn off with fuel and delivered to service station tanks. Customers fueling at these service stations pumped premium gasoline containing sea water and corrosion products into their automobiles. 

Figure 5. Ignition resistance of commercial premium gasolines...

The olefin content of the gasoline pool has decreased from 19% on a leaded basis to only 9% on a lead free basis. Aromatics, however, have increased from 21 to 42%, respectively, and are as high as 51% in the premium gasoline. 

Figure 5. Product distribution from partial oxidation reforming of premium gasoline using the ANL catalyst.

It is certain that world use of natural gas will increase dramatically in the near future as industrialized countries replace coal-fired facilities with cleaner-burning natural gas. In addition, a number of countries remote from major markets are in the process of installing world-scale plants for utilization of natural gas and gas liquids for production of fertilizers, methanol, premium gasoline blending stocks, and other basic petrochemical derivatives that will result in higher-value products from natural gas and gas liquids for which there are no local markets. 

Figure 028. Apparatus for the distillation of unleaded premium gasoline (carefully distill at 70 Celsius).

Milne TA, Evans RJ, Nagle N. 1990. Catalytic conversion of microalgae and vegetable oils to premium gasoline, with shape-selective zeolites. Biomass 21 219-232. 

Predict When you apply a hypothesis to a specific situation, you predict something about that situation. A prediction makes a statement in advance, based on prior observation, experience, or scientific reasoning. People use predictions to make everyday decisions. Scientists test predictions by performing investigations. Based on previous observations and experiences, you might form a prediction that cars are more efficient with premium gasoline. The prediction can be tested in an investigation. 

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