tetraetyylilyyttiä

Tetraetyylilyyttiä, chemical formula Pb(C2H5)4, also known as tetraethyl lead or TEL, is an organolead compound that was historically used as a gasoline additive. Its primary function was to increase the octane rating of gasoline, preventing engine knocking and allowing for higher compression ratios. This led to improved engine performance and fuel efficiency. TEL was synthesized by reacting chloroethane with sodium-lead alloy.

The use of tetraethyl lead began in the 1920s and it became widely adopted in leaded gasoline. However, as its use became widespread, concerns regarding its environmental and health impacts grew. Lead is a neurotoxin, and the combustion of TEL released lead compounds into the atmosphere. These lead particles could accumulate in soil and water, posing risks to human health, particularly to children, where exposure can lead to developmental problems.

Due to these environmental and health concerns, the use of tetraethyl lead has been phased out in most countries. Leaded gasoline was banned for on-road vehicles in the United States in 1996, and similar bans have been implemented globally. While its use in gasoline has largely ceased, TEL may still find limited applications in aviation gasoline or specific industrial processes, though these are also subject to increasing restrictions. The legacy of TEL's widespread use continues to be a subject of environmental remediation efforts.