Phthalic anhydride

  • 1,3-Isobenzofurandione
  • Phthalic acid anhydride
  • 1,2-Benzenedicarboxylic acid anhydride
  • 1,3 Dixophthalan
Formula
C8H4O3
Structure
Description
Thin white flakes with a characteristic choking odor.
Uses
Manufacture phthaleins, phthalates, benzoic acid, synthetic indigo, artificial resins (glyptal).

Registry Numbers and Inventories.
CAS
85-44-9
EC (EINECS/ELINCS)
201-607-5
EC Index Number
607-009-00-4
EC Class
Harmful; Irritant; Sensitising
R 22 37/38 41 42/43
S 23 24/25 26 37/39 46
RTECS
TI3150000
RTECS class
Tumorigen; Mutagen; Reproductive Effector; Primary Irritant
UN (DOT)
2214
Merck
12,7528
Beilstein/Gmelin
118515
Beilstein Reference
5-17-11-00253
RCRA
U190
Swiss Giftliste 1
G-2749
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Japan ENCS (MITI)
Listed
Korea ECL
Listed

Properties.
Formula
C8H4O3
Formula mass
148.12
Melting point, °C
131
Boiling point, °C
284
Vapor pressure, mmHg
0.0002 (20 C)
Vapor density (air=1)
6.6
Saturation Concentration
0.26 ppm at 20 C (calculated)
Odor Threshold Odor threshold 0.32-0.72 mg/m3
Critical temperature
609
Critical pressure
41.6
Density
1.545 g/cm3 (20 C)
Solubility in water
6.2 g/L (20 C)
Viscosity
1.125 cp (155 C)
Surface tension
35.5 g/s2 (115 C)
Dipole moment
5.25 D
Partition coefficient, pKow
1.12
Heat of fusion
23.26 kJ/mol
Heat of vaporization
54.01 kJ/mol
Heat of combustion
-3255 kJ/mol

Hazards and Protection.
Storage
Keep container closed when not in use. Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from water. Corrosives area.
D2A D2B
Handling
Wash thoroughly after handling. Use only in a well ventilated area. Use with adequate ventilation. Ground and bond containers when transferring material. Do not breathe dust, vapor, mist, or gas. Do not get in eyes, on skin, or on clothing. Empty containers retain product residue, (liquid and/or vapor), and can be dangerous. Keep container tightly closed. Do not ingest or inhale. Do not allow contact with water. Discard contaminated shoes. Do not pressurize, cut, weld, braze, solder, drill, grind, or expose empty containers to heat, sparks or open flames.
Protection
Wear impervious protective clothing, including boots, gloves, lab coat, apron or coveralls, as appropriate, to prevent skin contact. Rubber and neoprene are recommended materials for personal protective equipment. Use chemical safety goggles and/or full face shield where dusting or splashing of solutions is possible. Maintain eye wash fountain and quick-drench facilities in work area.
Respirators
A full-face piece respirator with an organic vapor cartridge and particulate filter (NIOSH type N100 filter) may be worn up to 50 times the exposure limit, or the maximum use concentration specified by the appropriate regulatory agency or respirator supplier, whichever is lowest. If oil particles (e.g. lubricants, cutting fluids, glycerine, etc.) are present, use a NIOSH type R or P particulate filter. For emergencies or instances where the exposure levels are not known, use a full-face piece positive-pressure, air-supplied respirator.
Small spills/leaks
Clean up spills immediately, using the appropriate protective equipment. Sweep up or absorb material, then place into a suitable clean, dry, closed container for disposal. Avoid generating dusty conditions. Remove all sources of ignition. Use a spark-proof tool. Provide ventilation. Do not get water inside containers.
Disposal code
4
Stability
Stable under ordinary conditions of use and storage. Heat will contribute to instability. When molten it should be covered with inert gas.
Incompatibilities
Strong oxidizers. nitric acid, sodium nitrite, copper oxide.
Decomposition
Carbon dioxide and carbon monoxide may form when heated to decomposition. Slowly reacts with water to form phthalic acid.

Fire.
Flash Point,°C
152
Autoignition, °C
570
Upper exp. limit, %
10.5
Lower exp. limit, %
1.7
Fire fighting
Wear full protective clothing and NIOSH-approved self-contained breathing apparatus with full facepiece operated in the pressure demand or other positive pressure mode. Extinguish fire with water spray, dry chemical, alcohol foam, or carbon dioxide. Water or foam may cause frothing.
Fire potential
May burn but does not ignite readily.
Hazards
Substance will react with water (some violently) releasing flammable, toxic or corrosive gases and runoff. When heated, vapors may form explosive mixtures with air: indoors, outdoors, and sewers explosion hazards. Most vapors are heavier than air. They will spread along ground and collect in low or confined areas (sewers, basements, tanks). Vapors may travel to source of ignition and flash back. Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated or if contaminated with water.
Combustion products
Fire will produce irritating, corrosive and/or toxic gases.
Health
3
 
Flammability
1
 
 
Reactivity
0
 

Health.
Exposure limit(s)
NIOSH REL: TWA 6 mg/m3 (1 ppm) OSHA PEL: TWA 12 mg/m3 (2 ppm) IDLH 60 mg/m3
Poison_Class
4
Exposure effects
Contact with water causes formation of phthalic acid, which is responsible for the corrosive effects. Corrosive effects may be delayed several hours. Chronic exposure by inhalation or skin contact can cause allergic sensitization. Causes liver and kidney effects in laboratory animals.
   Ingestion
Corrosive. Swallowing can cause severe burns of the mouth, throat, and stomach. Can cause sore throat, vomiting, diarrhea.
   Inhalation
Inhalation of vapor, fume or dust is a primary irritant. Coughing, choking, as well as headache and dizziness can occur. May cause allergic respiratory reaction.
   Skin
Corrosive. Symptoms of redness, pain, and severe burn can occur. May cause allergic skin reactions.
   Eyes
Conjunctival edema and corneal destruction can occur. Symptoms include pain, tearing, and photophobia.

First aid
 
   Ingestion
Do NOT induce vomiting. If victim is conscious and alert, give 2-4 cupfuls of milk or water. Never give anything by mouth to an unconscious person. 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. DO NOT use mouth-to-mouth respiration. If breathing has ceased apply artificial respiration using oxygen and a suitable mechanical device such as a bag and a mask.
   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. Wash clothing before reuse. Destroy contaminated shoes.
   Eyes
Get medical aid immediately. Do NOT allow victim to rub or keep eyes closed. Gently lift eyelids and flush continuously with water. Extensive irrigation is required (at least 30 minutes).

Transport.
UN number
2214
Response guide
Hazard class
8
Packing Group
III
 
USCG CHRIS Code
PAN
 
11 Organic anhydrides
HS Code
2917 35 00
 
Std. Transport #
4966150
 
IMO Chemical Code
17
IMO Pollution Category
C
IMO Hazard code
S/P