methanethiol

chemical compound

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June 30, 2026

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Methanethiol (CH₃SH) is a simple thiol, also known as methyl mercaptan. Thiols are organic compounds similar to alcohols but with a sulfur atom replacing the oxygen atom. They are known for their strong, often unpleasant odors, detectable in very small concentrations.12

Methanethiol is found in crude petroleum and has a low boiling point of 6°C (43°F). Due to its disagreeable odor, it is used as a warning agent in fuel-gas systems. While generally considered toxic, lower-molecular-weight thiols like methanethiol can be recovered from petroleum for use in manufacturing agricultural chemicals and other commodities.123

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organosulfur compound
Thiols
Low-molecular-weight thiols such as methanethiol (CH₃SH) are found in crude petroleum. As such, they pose serious problems, associated not only with objectionable odors but also with their corrosive effect on equipment and their ability to poison (render nonfunctional) catalysts for air-pollution control or for other chemical processes. If they…
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Low-molecular-weight thiols such as methanethiol (CH₃SH) are found in crude petroleum. As such, they pose serious problems, associated not only with objectionable odors but also with their corrosive effect on equipment and their ability to poison (render nonfunctional) catalysts for air-pollution control or for other chemical processes. If they…
Read More