Lead scavenger

Much of the bromine output in the U.S. was used in the production of ethylene dibromide, a lead scavenger used in making gasoline antiknock compounds. Lead in gasoline, however, has been drastically reduced, due to environmental considerations. This will greatly affect future production of bromine. 

Other uses of ethylene dichloride include its formulation with tetraethyl and tetramethyl lead solutions as a lead scavenger, as a degreasing agent, and as an intermediate in the synthesis of many ethylene derivatives. 

Used industrially as a chemical intermediate, solvent, dry cleaning fluid, degreaser, and lead scavenger for antiknock fluids used in agriculture as a fumigant. 

FIGU RE 4.16 Relative solubilities of BTEX, MTBE, and the lead scavengers EDC and EDB. 

Uses Preparation of tetrachloroethylene and carbon tetrachloride lead scavenger for antiknock fluids metal cleanser soil fumigant for nematodes solvent for oils, fats, gums, waxes, and resins spotting agent. 

Uses Lead scavenger was used in anti knock (leaded) gasoline grain and fruit fumigant waterproofing preparations insecticide medicines general solvent organic synthesis. 

Uses. A fumigant (now banned for soil and grain use) in gasoline as a lead scavenger chemical intermediate in the industrial synthesis of other brominated compounds... 

Alkyl lead compounds are extremely effective gasoline antiknock agents. By decomposing to form lead oxide compounds during the gasoline combustion process, lead alkyls interrupt the rapid chain scission reactions which lead to combustion knock. Also, lead alkyls help to prevent exhaust valve seat wear and may minimize octane requirement increase. However, unless utilized in conjunction with lead scavengers such as 1,2-dichloromethane, lead deposits can accumulate within the gasoline combustion chamber. 

The majority of 1,2-dichloroethane released into the environment enters the atmosphere from its production and use as a chemical intermediate, solvent and lead scavenger in gasoline. It has been detected at low levels in ambient and urban air, groundwater and drinking-water samples (United States National Library of Medicine, 1997). 

Catalyst-poisoning studies have concentrated on the potential poisons introduced with fuel, particularly on lead, which has been added intentionally to improve the combustion characteristics at the high compression ratios employed in modem internal combustion engines prior to the introduction of exhaust purification catalysts. The lead is usually introduced as motor mix which contains tetraethyllead in a mixture with organic halides, chlorides or bromides. These halides transport the lead in the form of volatile halides out of the engine and into the exhaust, and are hence termed lead scavengers. Thus the potential catalyst-poison elements associated with the additive mixture are Pb, Br, and Cl. 

Production of vinyl chloride solvent lead scavenger in lead petrol... 

Intramolecular Cyclization The 1,2-dihaloethanes (XCH2CH2X) are used as pesticides, lead scavengers. 

USE As plasticizer in vinyl plastics manuf, as flame-retardant, solvent for nitrocellulose, in cellulosic molding compositions, as additive to extreme pressure Lubricants, as a nonflammable fluid in hydraulic systems, as lead scavenger in gasoline Yust, Bame, U4S. pat. 2,889,212 (1959 to Shell) to sterilize certain surgical instruments ... 

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