Automobiles leaded gasoline

Patterson thought he could identify the culprit If the high concentrations of lead observed in a few surface waters of the Pacific were representative of the sea surface of the entire northern hemisphere, the bulk of this lead could be readily be accounted for as originating from leaded gasolines. The hypothesis was unproven, but Patterson immediately understood its social implications. Automobile exhaust emitted lead as soluble lead-halide particles, which humans and other mammals easily absorb. When Patterson reported his ocean sediment research in an encyclopedic, 45-page article in 1962, he handed a copy to a colleague saying, Read it. It s important. ... 

Leaded gasoline was one of the country s top ten industrial chemicals during the 1960s it accounted for 90 percent of all automobile fuel sold in the United States. As Esso ads proclaimed, there was a tiger in the tank of almost every American car. Between 1926 and 1985, more than seven million tons of lead were burned as fuel additives. In terms of sheer volume, leaded gasoline was one of the most important organic chemicals that modern society has produced. 

Jerome O. Nriagu. The Rise and Fall of Leaded Gasoline. The Science of the Total Environment. 92 (1990) 13-28. An authoritative history of leaded gasoline. The source for airplane octane lead industry pays Kehoe s salary one of few environmentally unsafe products forced out of market place one of top 10 chemicals in U.S. Esso slogan compression ratio and valve seat recession Kettering about automobile at crossroads, Europe versus U.S. 90 percent all U.S. gas and 80 percent worldwide autos after 20 years of TEL TEL drove U.S. transport lead removed from Ethyl trade name and Ethyl s control of publications and environment to be monitored by voluntary self-regulation, not legislation. 

Information available regarding the chemistry of lead in air is limited. Before the ban on sales of leaded gasoline, lead particles were emitted to the atmosphere from automobiles as lead halides (mostly PbBrCl) and as double salts with ammonium halides (e.g., 2PbBrCl NH4Cl. Pb3[P04]2, and PbS04 [Biggins and Harrison 1979 Ter Haar and Bayard 1971]). After 18 hours, approximately 75% of the bromine and 30-40% of the chlorine disappeared, and lead carbonates, oxycarbonates and oxides were produced. 

Dibromoethane releases to the atmosphere historically have been due to fugitive emissions from leaded gasolines, automobile exhaust, and the former use of the compound as a fumigant (Fishbein 1979). 

The two instruments most suited to the sputter depth profiling of individual particles are the Auger and ion microprobes. The characterization of automobile exhaust particles produced in the combustion of leaded gasoline will be used to illustrate this point. 

Lead aerosol in the air is poisonous to breathe, especially for young children. Many people called for the abolition of lead in gasoline. In the 1970s, the photochemical smog in California was attributed to unburned hydrocarbons and carbon monoxide from automobile tailpipes, and the best solution was the catalytic converter which works with finely divided platinum particles deposited on alumina monoliths. When leaded gasoline is used, these platinum atoms would be quickly covered by a barrage of lead aerosols. This finally led to the abolishment of TEL as a gasoline additive. 

It should be noted that Pb concentrations in this polluted air are about 100 times lower than the aerosol S levels, or are only a few tens of ng Pb/m. In the Beijing area the contribution of automotive emissions to atmospheric Pb at Xinglong is expected to be minor owing to the small amounts of leaded gasoline used privately owned automobiles, trucks, and other gasoline powered vehicles are nonexistent in China. Instead, coal combustion may be the principal source of fine particle Pb as well as K and S. 

Transportation sources, particularly automobiles, are a major source of air pollution and include smoke, lead particles from tetraethyl lead additives, CO, nitrogen oxides, and hydrocarbons. Since the mid-1960s there has been significant progress in reducing exhaust emissions, particularly with the use of low-lead or no-lead gasoline as well as... 

The 1974/75 slump in gasoline demand is over, the 1976 demand Is expected to top 6% while the 1977 demand will return to a more normal 3 to 5%. The question of lead phase-down appears relieved with an EPA postponement, but as a result of the steadily increasing number of vehicles that use unleaded gasoline (about 107o increase annually on the total number of automobiles in the United States) by 1980 some 62% of the total gasoline pool will have to meet no-lead gasoline specification. 

The MRSPC was applied to the in situ study of automobile exhaust gas emissions. A four-cylinder engine using both leaded gasoline fuel as well as a 15% methanol blend was used to investigate the particulate... 

Of the six heavy metals discussed in this chapter, Pb has been studied extensively with respect to the environmental effects. Clair Patterson, the father of environmental Pb studies, in one of his many major publications concerning the global Pb cycle (Patterson and Settle, 1987), noted that during pre-industrial times Pb in the troposphere originated from soil dusts and volcanic gases. In modern times (1950-1980) the proportion of natural Pb in the atmosphere is overwhelmed by the industrial sources of smelter emissions and automobile exhausts. Lead air pollution levels measured near our Nation s roadways decreased 97% between 1976 and 1995 due to the consequence of the Clean Air Act that eliminated leaded gasoline which interfered with the performance of catalytic converters. 

On a more local level, man s activities in the urban/suburban environment have produced a strong imprint of Pb on the land surface. In the US, automobile and truck travel are the primary means of moving people and goods around the continent. With the introduction of leaded gasoline in the 1950s, the mean annual atmospheric concentration of Pb nearly tripled in value. 

Since lead-containing antiknock additives of leaded gasolines rapidly destroy the activity of the catalytic emission control systems, unleaded gasolines have had to be used in automobiles fitted with this or related systems. However, since using this fuel modification also eliminates one of the main sources of lead emissions to the atmosphere, this trend also has a highly favorable additional impact [11, 12]. Before unleaded gasolines were on the market, it was common to find high lead levels in the core areas of busy cities... 

One of the most widely known examples of catalyst poisoning is taken from the automobile industry. Though tetra-ethyl lead has been removed from essentially all gasoline in North America, the ban on leaded gasoline is not worldwide, and leaded and unleaded gasoline is available in many countries. Catalytic converters, which contain precious metals like platinum, palladium, and rhodium, are used to both reduce NO c and oxidize CO and unburned hydrocarbons. Lead irreversibly destroys the catalytic ability of the converter. Concentrations of lead in leaded gasoline are nominally 150mg/L. 

The second part of this work consisted in testing a copper-chromite catalytic converter in an automobile ran with leaded gasoline (about 0.6 g Pb/1 ). 

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