sec-Butyl mercaptan

  • sec-Butanethiol
  • 2-Butanethiol
  • 2-Butyl mercaptan
  • sec-Butyl thioalcohol
  • sec-Butyl thiol
  • 2-Mercaptobutane
Formula
CH3CH2CH(SH)CH3
Structure
Description
Colorless liquid, obnoxious, heavy skunk-like odor.
Uses
Odorant for natural gas.

Registry Numbers and Inventories.
CAS
513-53-1
EC (EINECS/ELINCS)
208-165-2
EC Class
highly flammable
UN (DOT)
2347
Merck
12,1612
Beilstein/Gmelin
1718766
Beilstein Reference
4-01-00-01584
Swiss Giftliste 1
G-8024
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C4H10S
Formula mass
90.19
Melting point, °C
-165
Boiling point, °C
85
Vapor pressure, mmHg
74 (25 C)
Vapor density (air=1)
3.11
Density
0.8290 g/cm3 (20 C)
Solubility in water
Slightly soluble
Viscosity
0.463 cp (20 C)
Surface tension
23.1 g/s2 (30 C)
Refractive index
1.4338 (20 C)
pKa/pKb
10.69 (pKa)
Partition coefficient, pKow
2.13
Heat of fusion
6.48 kJ/mol
Heat of vaporization
86.6 kJ/mol

Hazards and Protection.
Storage
Keep in a cool, dry, dark location in a tightly sealed container or cylinder. Keep away from incompatible materials, ignition sources and untrained individuals. Secure and label area. Protect containers/cylinders from physical damage.
B2
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Wear appropriate protective gloves, clothing and goggles.
Respirators
Wear positive pressure self-contained breathing apparatus (SCBA).
Small spills/leaks
Make no contact with the spilled material. ELIMINATE all ignition sources and ground all equipment. Stop leak if you can do it without risk. A vapor suppressing foam may be used to reduce vapors. Absorb or cover with dry earth, sand or other non-combustible material and transfer to containers. Use clean non-sparking tools to collect absorbed material.
Disposal code
6
Stability
No data.

Fire.
Flash Point,°C
-23
Upper exp. limit, %
9.6
Lower exp. limit, %
1.7
Fire fighting
Use of water spray when fighting fire may be inefficient. Small Fires: Dry chemical, carbon dioxide, water spray or regular foam. Large Fires: Water spray, fog or regular foam. Do not use straight streams.
Fire potential
In general, mercaptans are flammable substances.
Hazards
Vapors may form explosive mixtures with air. Vapors may travel to source of ignition and flash back. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapor explosion hazard indoors, outdoors or in sewers.
Combustion products
Fire will produce irritating, corrosive and/or toxic gases.

Health.
Poison_Class
4
Exposure effects
Narcosis and paralysis may be caused with concentrated vapors. Drowsiness, weakness, and mild depression may be seen at exposures of 50 to 500 ppm for one hour.
   Ingestion
Nausea and vomiting have been reported in humans due to the refractory odor.
   Inhalation
Pulmonary edema was seen in animals near lethal concentrations.
   Skin
May irritate or burn. May cause toxic effects if absorbed through the skin.
   Eyes
See Skin.

First aid
 
   Ingestion
Seek medical assistance.
   Inhalation
Move victim to fresh air. Apply artificial respiration if victim is not breathing. Administer oxygen if breathing is difficult.
   Skin
Remove contaminated clothing and wash exposed area thoroughly with soap and water. A physician should examine the area if irritation or pain persists.
   Eyes
Irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes. If irritation, pain, swelling, lacrimation, or photophobia persist, the patient should be seen in a health care facility.

Transport.
UN number
2347
Response guide
Hazard class
3
Packing Group
II
 
HS Code
2930 90 70