Neil Alden Armstrong
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Then in the first 2 decades of the 20th century horseless carriages in increasing droves came looking for fuel. Researchers had found early on that the internal combustion engine ran best on light fuels like gasoline but distillation refining just didn't produce enough of it—only about 20 percent gasoline from a given amount of crude petroleum. Even as oil prospectors extended the range of productive wells from Pennsylvania through Indiana and into the vast oil fields of Oklahoma and Texas, the inherent inefficiency of the existing refining process was almost threatening to hold back the automotive industry with gasoline shortages. The problem was solved by a pair of chemical engineers at Standard Oil of Indiana—company vice president William Burton and Robert Humphreys, head of the lab at the Whiting refinery, the world's largest at the time. Burton and Humphreys had tried and failed to extract more gasoline from crude by adding chemical catalysts, but then Burton had an idea and directed Humphreys to add pressure to the standard heating process used in distillation. Under both heat and pressure, it turned out that heavier molecules of kerosene, with up to 16 carbon atoms per molecule, "cracked" into lighter molecules such as those of gasoline, with 4 to 12 carbons per molecule, Thermal cracking, as the process came to be called, doubled the efficiency of refining, yielding 40 percent gasoline. Burton was issued a patent for the process in 1913, and soon the pumps were keeping pace with the ever-increasing automobile demand. In the next decades other chemical engineers improved the refining process even further. In the 1920s Charles Kettering and Thomas Midgley, who would later develop Freon (see Air Conditioning and Refrigeration), discovered that adding a form of lead to gasoline made it burn smoothly, preventing the unwanted detonations that caused engine knocking. Tetraethyl lead was a standard ingredient of almost all gasolines until the 1970s, when environmental concerns led to the development of efficiently burning gasolines that didn't require lead. Another major breakthrough was catalytic cracking, the challenge that had escaped Burton and Humphreys. In the 1930s a Frenchman named Eugene Houdry perfected a process using certain silica and alumina-based catalysts that produced even more gasoline through cracking and didn't require high pressure. In addition, catalytic cracking produced forms of gasoline that burned more efficiently.Different forms of all sorts of things were coming out of refineries, driven in part by the demands of war. Houdry had also invented a catalytic process for crude oil that yielded butadiene, a hydrocarbon compound with some interesting characteristics. In the years before and during World War II it became one of two key ingredients in the production of synthetic rubber, an especially vital commodity as the war in the Pacific cut off supplies of natural rubber. The stage was now set for a revolution in petrochemical technology. As the war drove up demands for both gasoline and heavier aviation fuels, supplies of byproduct compounds—known as feedstocks—were increasing. At the same time, chemical engineers working in research labs were finding potential new uses for just those feedstocks, which they were beginning to see as vast untapped sources of raw material.
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