| Identification | More | [Name]
Molybdenum trioxide | [CAS]
1313-27-5 | [Synonyms]
MOLYBDENUM(+6)OXIDE
MOLYBDENUM OXIDE
MOLYBDENUM TRIOXIDE
MOLYBDENUM(VI) OXIDE
MOLYBDENUM(VI) OXIDE ON ALUMINA
MOLYBDIC ACID ANHYDRIDE
MOLYBDIC ANHYDRIDE
MOLYBDIC OXIDE
MOLYBDIC TRIOXIDE
Molylxlic trioxide
Mo 1202T
mo1202t
Molybdena
Molybdenum anhydride
Molybdenum oxide (MoO3)
Molybdenum oxide (MoO5)
Molybdenum peroxide
Molybdenumanhydride
molybdenumoxide(moo3)
molybdenumperoxide | [EINECS(EC#)]
215-204-7 | [Molecular Formula]
MoO3 | [MDL Number]
MFCD00003469 | [Molecular Weight]
143.94 | [MOL File]
1313-27-5.mol |
| Chemical Properties | Back Directory | [Appearance]
Molybdenum trioxide is an odorless, white
crystalline powder that turns yellow when heated. | [Melting point ]
795 °C(lit.)
| [Boiling point ]
1155 °C
| [density ]
4.692 | [vapor pressure ]
0Pa at 20℃ | [Fp ]
1155°C subl. | [storage temp. ]
Store at +5°C to +30°C. | [solubility ]
0.49g/l | [form ]
Sublimed Powder | [color ]
White to gray | [Specific Gravity]
4.69 | [Water Solubility ]
0.5 g/L (20 ºC) | [Merck ]
14,6239 | [Exposure limits]
ACGIH: TWA 10 mg/m3; TWA 3 mg/m3
NIOSH: IDLH 5000 mg/m3 | [InChIKey]
JKQOBWVOAYFWKG-UHFFFAOYSA-N | [CAS DataBase Reference]
1313-27-5(CAS DataBase Reference) | [IARC]
2B (Vol. 118) 2018 | [NIST Chemistry Reference]
Molybdenum(vi) oxide(1313-27-5) | [EPA Substance Registry System]
1313-27-5(EPA Substance) |
| Safety Data | Back Directory | [Hazard Codes ]
Xn,Xi | [Risk Statements ]
R36/37:Irritating to eyes and respiratory system .
R48/20/22:Harmful: danger of serious damage to health by prolonged exposure through inhalation and if swallowed . | [Safety Statements ]
S22:Do not breathe dust .
S23:Do not breathe gas/fumes/vapor/spray (appropriate wording to be specified by the manufacturer) .
S25:Avoid contact with eyes . | [WGK Germany ]
1
| [RTECS ]
QA4725000
| [TSCA ]
Yes | [HazardClass ]
6.1 | [HS Code ]
28257000 | [Safety Profile]
Poison by ingestion,
subcutaneous, and intraperitoneal routes.
Human systemic effects by inhalation:
pulmonary fibrosis and cough. Questionable
carcinogen with experimental neoplastigenic
data. A powerful irritant. Explodes on
contact with molten magnesium. Violent reaction with interhalogens (e.g., bromine
pentafluoride, chlorine trifluoride).
Incandescent reaction with hot sodium,
potassium, or lithium. When heated to
decomposition it emits toxic fumes of Mo. | [Hazardous Substances Data]
1313-27-5(Hazardous Substances Data) | [Toxicity]
LD50 orally in Rabbit: 2689 mg/kg LD50 dermal Rat > 2000 mg/kg |
| Hazard Information | Back Directory | [General Description]
Colorless to white or yellow odorless solid. Sinks in water. | [Reactivity Profile]
MOLYBDENUM TRIOXIDE(1313-27-5) reacts violently with chlorine trifluoride, lithium, potassium and sodium. Readily combines with acids and bases to form a series of polymeric compounds. Incompatible with interhalogens and metals. A violent detonation occurs when heated with molten magnesium. | [Air & Water Reactions]
Insoluble in water. | [Hazard]
Toxic material. | [Health Hazard]
Compound is relatively nontoxic. Dust irritates eyes. | [Potential Exposure]
Molybdenum trioxide is used in
agriculture; manufacture of metallic molybdenum, ceramic
glazes; enamels, pigments, and in analytical chemistry. | [Fire Hazard]
Flash point data for this chemical are not available, but MOLYBDENUM TRIOXIDE is probably non-flammable. | [First aid]
Move victim to fresh air. Call 911 or emergency
medical service. Give artificial respiration if victim is not
breathing. Do not use mouth-to-mouth method if victim
ingested or inhaled the substance; give artificial respiration
with the aid of a pocket mask equipped with a oneway
valve or other proper respiratory medical device.
Administer oxygen if breathing is difficult. Remove and
isolate contaminated clothing and shoes. In case of contact
with substance, immediately flush skin or eyes with running
water for at least 20 minutes. For minor skin contact,
avoid spreading material on unaffected skin. Keep victim
warm and quiet. Effects of exposure (inhalation, ingestion,
or skin contact) to substance may be delayed. Ensure that
medical personnel are aware of the material(s) involved
and take precautions to protect themselves. Medical observation
is recommended for 24 to 48 hours after breathing
overexposure, as pulmonary edema may be delayed.
As first aid for pulmonary edema, a doctor or authorized
paramedic may consider administering a drug or other
inhalation therapy. | [Shipping]
UN2811 Toxic solids, organic, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name
Required. | [Incompatibilities]
Explodes on contact with molten
magnesium. Violent reaction with strong oxidizers, such as
chlorine trifluoride; bromine pentafluoride. Not compatible
with strong acids; active metals (sodium, potassium,
lithium). | [Description]
Molybdenum trioxide is an odorless, whitecrystalline powder that turns yellow when heated; Freezing/Melting point 5 795℃. Hazard Identification (based onNFPA-704 M Rating System): Health 2, Flammability 0,Reactivity 0. Slightly soluble in water. | [Chemical Properties]
Molybdenum trioxide is an odorless, white crystalline powder that turns yellow when heated.
Molybdenum trioxide is perhaps the most important compound of molybdenum. Pure molybdenum trioxide is used in chemical and catalyst manufacture. The technical product is added to steel as an alloying agent. Molybdenum trioxide also serves as a catalyst in the petroleum industry and as a component of ceramics, enamels and pigments.
| [Physical properties]
Soft white powder; orthorhombic crystals; turns yellow on heating; density 4.69 g/cm3 at 21°C; melts at 795°C without decomposition to a dark yellow liquid; vapor pressure 20 torr at 851°C and 200 torr at 1,014°C; boils at 1,155°C; sparingly soluble in cold water (1.066 g/L at 18°C) and moderately soluble in hot water (20.55 g/L at 70°C); dissolves in acids and alkalies. | [Definition]
ChEBI: Molybdenum trioxide is a molybdenum oxide. | [Flammability and Explosibility]
Nonflammable | [storage]
Color Code—Blue: Health Hazard/Poison: Storein a secure poison location. Prior to working with thischemical you should be trained on its proper handling andstorage. Molybdenum trioxide must be stored to avoid contact with strong acids (such as hydrochloric, sulfuric, andnitric); alkalis, sodium, potassium, and molten magnesiumsince violent reactions occur. Store in tightly closed containers in a cool, well-ventilated area. | [Purification Methods]
Crystallise it from water (1g/50mL) between 70o and 0o. The solubility in H2O is 0.1% at 18o, and 2% at 70o. It is a white powder which turns yellow reversibly on heating. It sublimes readily at 1155o/760mm. [Hein & Herzog Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II p 1412 1965.] |
| Questions and Answers (Q&A) | Back Directory | [Uses]
Molybdenum(VI) oxide is used in catalyst compositions to carry out desulfurization of petroleum feedstocks and to remove nitrogen-containing compounds from petroleum fractions. Other uses of this oxide include preparation of various molybdate salts and as reagents for chemical analyses.
| [Preparation]
Molybdenum(VI) oxide is obtained by igniting molybdenum or its compounds in air:
2Mo + 3O2 → 2MoO3
2MoS2 + 7O2 → 2MoO3 + 4SO2
MoS2 + 4O2 → MoO3 + SO2 + SO3
Roasting the sulfide is carried out in a multiple-hearth roaster under controlled temperature and airflow. The product mixture is sublimed to obtain high purity oxide.
Purified molybdenum(VI) oxide also is made by prolonged heating of ammonium molybdate in air:
(NH4)2Mo2O7 → 2MoO3 + 2NH3 + H2O
An alternative method involves repeatedly evaporating a mixture of ammonium molybdate and nitric acid. Ammonium nitrate so formed is separated from the product molybdenum(VI) oxide by extraction with water:
(NH4)2Mo2O7 + 2HNO3 → 2MoO3 + 2NH4NO3 + H2O
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