Of automotive gasoline

Since 1946, hydroformer operation has been shifted largely to the production of automotive gasoline or benzene and aromatic solvents. These types of operation have been described in the literature in recent years (5, 5, 7). 

FIGURE 2-3. Existing Information on Health Effects of Automotive Gasoline... 

Fig. 9.2 Map of secondary atomization regimes as functions of Ohnesorge and Weber numbers, in which the areas representative of automotive gasoline and diesel sprays are identified...

J. D. Benson and co-workers. Effects of Gasoline Sulfur on Mass Exhaust Emissions—-Autoj Oil Air Quality Improvement Research Program, SAE 912323, Society of Automotive Engineers, Warrendale, Pa., 1991. 

Zhao, F., D.L. Harrington, and M.C. Lai, Automotive Gasoline Direct-Injection Engines, Warrendale, PA Society of Automotive Engineers, 2002. 

ATSDR. 1995. Toxicological profile for automotive gasoline. Agency for Toxic Substances and Disease Registry, Division of Toxicology, Atlanta, GA. 

Sometimes, part design requires multiple polymer layers. For example, an automotive gasoline tank can consist of both nylon and crosslinked polyethylene to provide combined chemical [-, resistance and strength, To produce multilayered parts, the first polymer, which will form... 

Three-way catalysts are used in most 1981 gasoline-fueled automobiles to lower the levels of NO, CO, and hydrocarbons in engine exhaust. These catalysts normally operate under dynamic conditions catalyst temperature increases rapidly after the engine starts (during catalyst "warmup"), and exhaust flowrate and composition fluctuate under most modes of operation. The warmup of automotive catalysts is reasonably well understood (1). The operation of three-way catalysts in the dynamic exhaust environment after warmup is complex and less well understood. 

As an example, when automotive catalytic mufflers and converters were introduced many years ago, the automobile industry required the petrochemical industry to eliminate lead from gasoline since lead degraded and reduced the effectiveness of the catalyst and caused the destruction of the gasoline. One set of industrial compounds that can harm catalysts are halogens, a family of compounds that include chlorine, bromine, iodine, and fluorine. Bromine, while not prevalent in industry, is present in chemical plants. Freons are fluorine compounds. Silicone is another compound that is deleterious to catalysts. It is used as a slip agent, or a lubricant, in many industrial processes. Phosphorous, heavy metals (zinc, lead), sulfur compounds, and any particulate can result in shortening the life of the catalyst. It is necessary to estimate the volume or the amount of each of those contaminants, to assess the viability of catalytic technologies for the application. 

There are numerous refining methods employed to extract the fractions of petroleum liquids and gases. A particular refinery process design is normally dependent on the raw feedstock characteristics (e.g., crude oil and produced gas natural specifications) and the market demands (e.g., aviation or automotive gasolines), which it intends to meet. 

Automotive gasoline contains 150 or more different chemical compounds and the relative concentrations of the compounds vary considerably, depending on the source of crude oil, refinery process, and product specifications. Typical hydrocarbon constituents are (volume basis) alkanes (4 to 8%), alkenes (2 to 5%), isoalkanes (25 to 40%), cycloalkanes (3 to 7%), cycloalkenes (1 to 4%), and aromatics (20 to 50%). However, these proportions vary greatly. 

Evaporative processes are very important in the weathering of volatile petroleum products and may be the dominant weathering process for gasoline. Automotive gasoline, aviation gasoline, and some grades of jet fuel (e.g., JP-4) contain 20 to 99% highly volatile constituents (i.e., constituents with fewer than nine carbon atoms). 

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