antiknock agent

chemistry

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June 18, 2026

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An antiknock agent is a substance added to gasoline to prevent detonation, or "knocking," in internal-combustion engines. Knocking occurs when the fuel-air mixture in the engine's cylinder burns too rapidly, reducing efficiency and potentially damaging the engine.123

Historically, tetraethyllead was a common antiknock agent, significantly improving the octane number of gasoline. However, due to lead's toxicity and its interference with pollution-control devices, leaded gasoline has been phased out globally. Modern gasoline formulations rely on different blends and additives to achieve the necessary antiknock quality.435

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Fuel
…gasoline are its volatility and antiknock quality. Volatility is a measure of the ease of vaporization of gasoline, which is adjusted in the production process to account for seasonal and altitude variations in the local market. Properly formulated gasoline helps engines to start in cold weather and to avoid vapour…
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…gasoline are its volatility and antiknock quality. Volatility is a measure of the ease of vaporization of gasoline, which is adjusted in the production process to account for seasonal and altitude variations in the local market. Properly formulated gasoline helps engines to start in cold weather and to avoid vapour…
Read More