Propylene oxide

Propylene oxide - Names and Identifiers

Name	Propylene oxide
Synonyms	PO Epoxypropane PROPYLENOXIDE Methyloxirane Propyleneoxide 2-Methyloxiran Propylene oxide 1,2-Epoxypropane PROPYLENEOXIDE,REAGENT 1,2-Epoxypropane(Propylene oxide) (±)-Methyloxirane, 1,2-Epoxypropane propylene oxide 1,2-epoxypropane methyloxirane
CAS	75-56-9
EINECS	200-879-2
InChI	InChI=1/C3H6O/c1-3-2-4-3/h3H,2H2,1H3

Propylene oxide - Physico-chemical Properties

Molecular Formula	C3H6O
Molar Mass	58.08
Density	0.83g/mLat 25°C(lit.)
Melting Point	-112 °C
Boling Point	34°C(lit.)
Flash Point	−35°F
Water Solubility	40 g/100 mL (20 ºC)
Solubility	425-450g/l
Vapor Presure	29.43 psi ( 55 °C)
Vapor Density	2 (vs air)
Appearance	Liquid
Color	Clear
Odor	Ethereal; characteristic; sweet, alcoholyc; like natural gas.
Exposure Limit	TLV-TWA 50 mg/m3(20 ppm) (ACGIH),240 mg/m3(100 ppm) (OSHA); IDLH2000 ppm.
Merck	14,7856
BRN	79763
Storage Condition	2-8°C
Stability	Stable. Incompatible with acids, bases, oxidizing agents, copper, copper alloys, brass, bronze, iron, metal chlorides, peroxides and a wide variety of other materials. Reacts with compounds containing
Explosive Limit	1.9-36%(V)
Refractive Index	n20/D 1.366(lit.)
Physical and Chemical Properties	Colorless, low-boiling flammable liquid with ether odor. Industrial products are racemic mixtures of two optical isomers. melting point boiling point 34.24 ℃ freezing point -112.13 ℃ relative density 0.859 refractive index 1.3664 flash point <-37 ℃ solubility partially miscible with water [40.5% by weight solubility in water at 20 °c; water has a solubility of 12.8% by weight in propylene oxide], is miscible with ethanol, diethyl ether, and forms a binary azeotrope with dichloromethane, pentane, pentene, cyclopentane, cyclopentene, etc.
Use	Important petrochemical raw materials for the production of Polyether, propylene glycol, surfactant, foaming agent, demulsifier, mineral processing agents

Propylene oxide - Risk and Safety

Risk Codes	R45 - May cause cancer R46 - May cause heritable genetic damage R12 - Extremely Flammable R20/21/22 - Harmful by inhalation, in contact with skin and if swallowed. R36/37/38 - Irritating to eyes, respiratory system and skin.
Safety Description	S53 - Avoid exposure - obtain special instructions before use. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.)
UN IDs	UN 1280 3/PG 1
WGK Germany	3
RTECS	TZ2975000
TSCA	Yes
HS Code	2910 20 00
Hazard Class	3
Packing Group	I
Toxicity	LD50 orally in rats: 1.14 g/kg (Smyth)

Propylene oxide - Upstream Downstream Industry

Raw Materials	Propylene Chlorine Calcium hydroxide Sodium hydroxide Calcium oxide
Downstream Products	1,2-Propanediol 1-butoxypropan-2-ol hydroxypropyl acrylate, mixture of isomers methylacrylate Dimethyl carbonate Propylene carbonate Tris(2-hydroxypropyl)amine 2-Methylpiperazine

Propylene oxide - Reference Information

Open Data Unverified Data

freezing point	-112.13 ℃
Henry's Law Constant	Not an environmentally important parameter because propylene oxide reacts rapidly with water
(IARC) carcinogen classification	2B (Vol. Sup 7, 60) 1994
NIST chemical information	information provided by: webbook.nist.gov (external link)
EPA chemical substance information	information provided by: ofmpeb.epa.gov (external link)
Use of propylene oxide	propylene oxide is a good low boiling solvent and raw material for organic synthesis, can be used for the preparation of propylene glycol, glycerin, propylene glycol, polyester resin, foam and surfactant. It can also be used as a solvent for cellulose acetate, cellulose nitrate, resins and the like. Propylene oxide reacts with ammonia to generate isopropanolamine (Monoisopropanolamine, diisopropanolamine, triisopropanolamine). Isopropanolamine is alkaline and can absorb acid gas, which is widely used in gas purification, such as desulfurization in ammonia industry, carbon dioxide removal, etc. The usage of propylene oxide for various purposes: Polyether polyol (the main raw material of polyurethane foam) 60%, propylene glycol (the raw material of Unsaturated Polyester Resin) 8%~ 10%, reinforced Plastics and non-toxic solvents, etc. 20% ~ 25%, surfactant 5%~ 10%. In 1860, propylene oxide was first synthesized in the laboratory by B. In 1931, the United Carbide Company of the United States built the world's first plant for the production of propylene oxide by chlorohydrin method. Indirect oxidation processes were developed in Spain and the United States in the 1960s. At present, these 2 methods are produced, each accounting for 50%, but the latter has a tendency to come to the top.
toxicity	the toxicity of propylene oxide is smaller than that of ethylene oxide, which is mainly stimulative effect, and has mild anesthetic and protoplasmic toxicity. Direct contact can stimulate the skin, severe cases cause skin necrosis. The olfactory threshold was 360mg/m3. Several minutes after inhalation of high concentration, the patient was poisoned, with eye and upper respiratory tract irritation symptoms, Dyspnea, head pain, dizziness, weakness, calf muscle spasm, gait instability, Nausea, Vomit and Diarrhea, restlessness, delirium, Coma. Elevated blood pressure, arrhythmia, myocardial damage, gastrointestinal bleeding, toxic intestinal paralysis and liver and kidney damage can be seen in the course of the disease. because its toxic symptoms may be related to the increase of histamine and other bioactive substances in the body, it can be treated with anti-histamine drugs and sodium thiosulfate. The threshold value of propylene oxide in workshop air is temporarily set at 240mg/m3 (TLV-TWA, US, 1980), and the maximum allowable concentration is 1mg/m3 (Su, 1972). LD50580mg/kg (mouse, oral) directly inhaled its vapor can cause Vomit, Diarrhea, Coma.
identification test	solubility 1g is dissolved in OT-42 of water, miscible in ethanol and diethyl ether ().
content analysis	the same as the content analysis method in "07115, Ethylene Oxide", but the formula is changed to: Propylene oxide (%) = NaOH solution volume (ml)× 0.0581/sample mass × 100% (a)
Use limit	Disinfection the maximum allowable concentration of the site is 1mg/m3.
uses	mainly used in the production of propylene glycol, polyether polyol, polypropylene glycol, propylene glycol ether and synthetic glycerin, also used in the manufacture of isopropanolamine, propylene carbonate, etc. used in organic synthesis and plastic manufacturing, also used as solvent, chromatographic analysis standard material propylene oxide is an intermediate of the herbicide metolachlor, and is also an important organic synthesis chemical raw material, propylene glycol, allyl alcohol, propionaldehyde, isopropylamine, synthetic glycerin, organic acids and the like can be produced, and Nonionic Surfactants, wetting agents, emulsifiers, detergents and the like can also be produced. propylene oxide is an important organic chemical raw material and the third largest product of propylene series. Its biggest use is to prepare polyols (polyethers) and then to produce polyurethane, in the United States and Western Europe, these uses account for more than 60% and 70%, respectively. Propylene oxide is used to prepare Nonionic Surfactant, propylene glycol, isopropanolamine, propionaldehyde, synthetic glycerin, organic acid, synthetic resin, foam plastic, plasticizer, emulsifier, wetting agent, detergent, bactericide, fumigant, etc. Propylene oxide-derived fine chemicals are used in almost all industrial sectors and in daily life. germicidal disinfectant. important petrochemical raw materials, used in the production of Polyether, propylene glycol, surfactant, foaming agent, demulsifier, mineral processing agent, etc.
production method	chloropropanol is generated from propylene, chlorine and water at atmospheric pressure and 60 ℃, and then saponified, condensed, obtained by distillation. From the oxidation of ethylbenzene to ethylbenzene peroxide, in the catalytic naphthenic acid molybdenum, and propylene cyclization. There are mainly chlorine alcohol method and indirect oxidation method. 1. Chlorohydrin method from propylene and chlorine, water at atmospheric pressure and 60 ℃ by hypochlorous acid to generate chloropropanol, then saponification, condensation, distillation derived. 2. Indirect oxidation of ethylbenzene (or isobutane, cumene, etc.) by oxidation of ethylbenzene hydroperoxide (or tert-butyl hydroperoxide, cumene hydroperoxide, etc.), in the presence of catalysts such as molybdenum naphthenate, it is obtained by The epoxidation reaction with propylene. 3. Electrochemical chlorohydrin method this method uses an aqueous solution of sodium chloride (or potassium chloride, sodium bromide, sodium iodide) to generate chlorine gas and sodium hydroxide by electrolysis. Propylene is introduced into the anode region to generate chloropropanol, the reaction of chloropropanol with sodium hydroxide in the cathode zone generates propylene oxide. There are several preparation methods. (1) chlorohydrin method with propylene as raw material, by hypochlorous acid, saponification, and then by concentration, distillation and product. The reaction of propylene and hypochlorous acid is carried out in an aqueous solution, and chlorine gas is mixed with hypochlorous acid and hydrochloric acid in a state of equilibrium in water, and the reaction temperature is 30-50 ℃, the resulting hydrous chloropropanol and 10% milk of lime are saponified in a saponification kettle. Steam is introduced into the saponification kettle, and the produced propylene oxide is distilled and then subjected to condensation rectification to obtain a finished product. CH3CH = CH2 + HOCl → CH3CHOHCH2Cl + CH3CHClCH2OH this method does not require high purity of propylene and high yield, but requires a large amount of chlorine gas and lime milk, which causes serious equipment corrosion, this method is mainly used to produce propylene oxide in our country because of the problem of environmental pollution. (2) the main process of peroxide method is the production of organic hydrogen peroxide, and propylene is oxidized by peroxide. This reaction, whether it is the production of organic hydrogen peroxide or the transfer of oxygen from the peroxide to the propylene molecule in the presence of a catalyst, is a liquid-phase reaction in which, in addition to the main product, propylene oxide, there are co-products. At present, there have been achieved the industrialization of the ethyl benzene and the method of isobutane. Ethylbenzene hydroperoxide is prepared from ethylbenzene by oxidation, Epoxidation of propylene is carried out in the presence of a catalyst such as copper naphthenate to obtain propylene oxide and α-phenylethanol. Styrene can be obtained by dehydration. The reaction temperature of ethylbenzene oxidation is 130~150 ℃, the pressure is 0.07~0.14 MPa, the selectivity of ethylbenzene hydroperoxide is 90%, and the epoxidation temperature is 50~120 ℃, the pressure is normal pressure ~ 0.864 MPa. For example, a mixture of ethylbenzene hydroperoxide 14%, propylene 35%, ethylbenzene 50%, and α-phenylethanol 1%(mass fraction) is added to 0.4% manganese Naphthenate-sodium naphthenate (nMo/nNa = 2, molar ratio). As a catalyst, reaction at 100 ℃ for 1.5 h, the conversion of ethylbenzene hydroperoxide was 99%, and the selectivity of propylene oxide was 78%. The reaction product was treated by distillation to obtain propylene oxide product, in the dehydration reactor, α-phenylethanol was dehydrated at 250 to 280 ° C. Using TiO3-Al2O3 as a catalyst, and 100% was converted to styrene with a selectivity of 92%. The characteristics of this method: low cost, economic and reasonable, less three wastes, and combined production of styrene. Isobutane-hakang method takes isobutane as raw material, and then reacts with the oxidant tert-butyl hydroperoxide to obtain propylene oxide and tert-butyl alcohol. Tert-butyl hydroperoxide is prepared at 100~110 deg C, without catalyst, usually with tert-butyl hydroperoxide as initiator, propylene epoxidation reaction conditions are reaction temperature 121 deg C, pressure 4.1 MPa. The reaction was carried out in the presence of molybdenum catalyst for 0.5 h. The yield of propylene oxide was 88% (calculated as peroxide) and the selectivity was 81%. This method can produce tert-butyl alcohol, the yield is about 60%,(CH3)2CHCH3 + O2 →(CH3)3COOH +(CH3)3COH
category	flammable liquid
toxicity grade	high toxicity
Acute toxicity	oral-rat LD50: 380 mg/kg; Oral-mouse LD50: 440 mg/kg
stimulation data	Skin-rabbit 415 mg moderate; Eye-rabbit 20 mg severe
explosive hazard characteristics	in case of ammonia, chlorosulfonic acid, hydrochloric acid, hydrogen fluoride, nitric acid, sulfuric acid and fuming sulfuric acid can be exploded
flammability hazard characteristics	in case of open flame, high temperature, flammable oxidant; Combustion stimulus smoke
storage and transportation characteristics	The warehouse is ventilated and dried at low temperature; Stored separately from oxidants and acids
extinguishing agent	dry powder, dry sand, carbon dioxide, foam, 1211 extinguishing agent
Occupational Standard	TWA 100 PPM
spontaneous combustion temperature	430°C
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)
immediate life-and health-threatening concentration	400 ppm

Last Update：2024-04-09 19:43:38

Propylene oxide - Nature

Open Data Verified Data

colorless, low-boiling flammable liquid with ether odor. The industrial product is a racemic mixture of two optical isomers. Freezing point -112.13 °c. Boiling point 34. 24 °c. The relative density was 0.859. Flash point <-37 °c, refractive index 3664. Viscosity (25 ℃)0.28mPa.s is partially miscible with water [40.5% by weight solubility in water at 20 °c; Water solubility in propylene oxide 12. 8% by weight] is miscible with ethanol, ether, and forms a binary azeotrope with dichloromethane, pentane, pentene, cyclopentane, cyclopentene, etc.

Last Update：2024-01-02 23:10:35

Propylene oxide - Preparation Method

Open Data Verified Data

There are mainly chlorine alcohol method and indirect oxidation method.

chlorohydrin method from propylene and chlorine gas, water under normal pressure and 60 deg C by hypochlorous acid to produce chloropropanol, and then saponification, condensation, distillation.
indirect oxidation of ethylbenzene (or isobutane, cumene, etc.) via oxidation to ethylbenzene hydroperoxide (or tert-butyl hydroperoxide, cumene hydroperoxide, etc, it is obtained by The epoxidation reaction with propylene.
electrochemical chlorohydrin method this method uses an aqueous solution of sodium chloride (or potassium chloride, sodium bromide, sodium iodide) to generate chlorine gas and sodium hydroxide by electrolysis. Propylene is introduced into the anode region to generate chloropropanol, the reaction of chloropropanol with sodium hydroxide in the cathode zone generates propylene oxide.

Last Update：2022-01-01 10:15:27

Propylene oxide - Use

Open Data Verified Data

important raw materials for organic synthesis, used in the manufacture of propylene glycol, propylene glycol, propionaldehyde, synthetic glycerin, organic acids, synthetic resins, foams, plasticizers, surfactants, emulsifiers, wetting agents, detergents, bactericide, fumigant, etc.

Last Update：2022-01-01 10:15:27

Propylene oxide - Safety

Open Data Verified Data

propylene oxide is a toxic substance, which has a stimulating effect on skin and mucosa, can damage the cornea and conjunctiva of the eye, cause pain in respiratory organs, swelling and burning of skin, and even cause tissue necrosis. Inhalation of its vapor can affect the central nervous system, showing depression and Vomit, Diarrhea, Coma, collapse and other symptoms. Mouse oral ld50580 mg/kg. The maximum allowable concentration in the air of the workplace is 1mg/m3. Operators should wear gas masks, goggles, and protective gloves.
propylene oxide is a low-boiling, flammable liquid, the vapor can spontaneous combustion or explosion in the air, should be stored in accordance with the provisions of toxic dangerous goods. The storage tanks and reactors, etc. are preferably covered with an inert gas. The temperature and pressure of the container should be maintained at 25 °c and 0. 3MPa or less. Relevant fire and explosion prevention measures shall be implemented. Storage and transport containers should be made of stainless steel.

Last Update：2022-01-01 10:15:28