3-Mercaptopropionic acid

  • beta-Mercaptopropanoic acid
  • 3-Thiopropionic acid
Formula
HSCH2CH2COOH
Structure
Description
Amorphous crystals or clear liquid, strong, acrid, sulfide-like odor, stench.
Uses
Stabilizer, antioxidant, catalyst, chemical intermediate.

Registry Numbers and Inventories.
CAS
107-96-0
EC (EINECS/ELINCS)
203-537-0
EC Class
toxic, corrosive
R 25 34
S 26 36/37/39 45
RTECS
UF5270000
RTECS class
Other
UN (DOT)
2922
Beilstein/Gmelin
773807
Beilstein Reference
4-03-00-00726
Swiss Giftliste 1
G-8994
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C3H6O2S
Formula mass
106.14
Melting point, °C
17 - 19
Boiling point, °C
217
Vapor pressure, mmHg
0.05 (25 C)
Density
1.2199 g/cm3 (20 C)
Solubility in water
Soluble
Refractive index
1.491 (20 C)
pKa/pKb
4.34 (pKa)
Partition coefficient, pKow
0.43
Heat of vaporization
50.0 kJ/mol
Heat of combustion
-2142 kJ/mol

Hazards and Protection.
Storage
Keep away from sources of ignition. Store in a cool, dry place. Store in a tightly closed container. Corrosives area.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Do not get in eyes, on skin, or on clothing. Avoid contact with heat, sparks and flame. Do not ingest or inhale. Use only in a chemical fume hood.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves and clothing to prevent skin exposure. Clothing: Wear appropriate protective clothing to prevent skin exposure.
Respirators
Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.
Small spills/leaks
Absorb spill with inert material, (e.g., dry sand or earth), then place into a chemical waste container.
Disposal code
6
Stability
Has not been fully evaluated.
Incompatibilities
Bases - oxidizing agents - reducing agents.
Decomposition
Carbon monoxide, oxides of sulfur, carbon dioxide.

Fire.
Flash Point,°C
93
Autoignition, °C
350
Lower exp. limit, %
2.2
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Will burn if involved in a fire. To extinguish fire use water spray, dry chemical, carbon dioxide, or chemical foam.
Fire potential
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes.
Hazards
Contact with metals may evolve flammable hydrogen gas.
Combustion products
Fire may produce irritating, corrosive and/or toxic gases.

Health.
Poison_Class
2
Exposure effects
   Ingestion
Harmful if swallowed. Causes gastrointestinal tract burns. May cause perforation of the digestive tract.
   Inhalation
May cause irritation of the respiratory tract with burning pain in the nose and throat, coughing, wheezing, shortness of breath and pulmonary edema. Causes chemical burns to the respiratory tract.
   Skin
Causes skin burns.
   Eyes
Causes eye burns.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid immediately.
   Inhalation
Get medical aid immediately. Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen.
   Skin
Get medical aid immediately. Immediately flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes.
   Eyes
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.
UN number
2922
Response guide
Hazard class
8
Packing Group
I; II; III
 
HS Code
2930 90 70