alpha-Butene

alpha-Butene - Names and Identifiers

Name	1-butene
Synonyms	1-C4H8 1-BUTENE 1-butene Butene-1 But-1-ene -Butylene cis-butene alpha-Butene trans-butene .beta.-Butene Polybut-1-ene .alpha.-Butene alpha-Butylene 1-butene, homopolymer
CAS	106-98-9
EINECS	203-449-2
InChI	InChI=1/C4H8/c1-3-4-2/h1-4H2
InChIKey	VXNZUUAINFGPBY-UHFFFAOYSA-N

alpha-Butene - Physico-chemical Properties

Molecular Formula	C4H8
Molar Mass	56.11
Density	0.5951
Melting Point	−185°C(lit.)
Boling Point	−6.3°C(lit.)
Flash Point	80
Water Solubility	222 mg/kg at 25 °C (shake flask-GC, McAuliffe, 1966)
Solubility	Soluble in alcohol, benzene, and ether (Weast, 1986)
Vapor Presure	1939 mm Hg ( 21.1 °C)
Vapor Density	1.93 (vs air)
Appearance	gas
Color	Colorless to Almost colorless
Odor	Slightly aromatic
Merck	14,1519
BRN	1098262
pKa	>14 (Schwarzenbach et al., 1993)
Storage Condition	-20°C Freezer
Stability	Volatile
Explosive Limit	9.3%
Refractive Index	1.3962
Physical and Chemical Properties	Boiling point -6.25 ℃ freezing point -185.35 ℃ relative density 0.5951 refractive index 1.3962 flash point -80 ℃ solubility insoluble in water, soluble in ethanol, ether, benzene-soluble.
Use	Mainly used for dehydrogenation to butadiene, also can be synthesized by water n-butanol

alpha-Butene - Risk and Safety

Risk Codes	12 - Extremely Flammable
Safety Description	S9 - Keep container in a well-ventilated place. S16 - Keep away from sources of ignition. S33 - Take precautionary measures against static discharges.
UN IDs	UN 1012 2.1
WGK Germany	-
FLUKA BRAND F CODES	4.5-31
Hazard Note	Extremely Flammable
Hazard Class	2.1
Packing Group	II

alpha-Butene - Nature

Open Data Verified Data

is a colorless, flammable gas at room temperature and atmospheric pressure. 1-Butene is soluble in ethanol and ether, insoluble in water. Easy to liquefy. In a low-pressure cylinder, it is shipped as liquefied petroleum gas at its own vapor pressure of 162kPa.

Last Update：2024-01-02 23:10:35

alpha-Butene - Hair-making

Open Data Verified Data

Industrial 1-butene (content 97%) was used as raw material, dried through silica gel, and then sent to a low-temperature rectification column. The Feed gas is condensed and liquefied by liquid nitrogen refrigerant in the distillation kettle, and then subjected to fractional distillation. It can be purified by batch distillation.

Last Update：2022-01-01 09:31:42

alpha-Butene - Use

Open Data Verified Data

used as standard gas and preparation of special standard mixture.

Last Update：2022-01-01 09:31:42

alpha-Butene - Safety

Open Data Verified Data

1-butene acts as an anesthetic at high concentrations. Its toxicity is about 4.5 times that of ethylene, skin contact liquid 1 butene will produce frostbite. After inhalation can appear shortness of breath, slow, muscle disorders, misjudgment, fatigue, Nausea, Vomit and other symptoms. The staff should be protected and the working environment should be well ventilated. Flammable, the cylinder should be stored in a well-ventilated place, away from the heat source and fire, not with oxygen, chlorine, strong oxidant or combustible stored together.

Last Update：2022-01-01 09:31:42

alpha-Butene - Reference Information

olfactory threshold (Odor Threshold)	0.36ppm
freezing point	-185.35 ℃
Henry's Law Constant	(atm?m3/mol):0.25 at 25 °C (Hine and Mookerjee, 1975)
LogP	2.35 at 20℃
EPA chemical information	Information provided by: ofmpub.epa.gov (external link)
Overview	n-butene is a colorless gas under normal conditions with a weak aromatic smell. It is used to make butadiene, methyl ketone, ethyl ketone, sec-butanol, butylene oxide and butene polymers and copolymers.
use	1-butene is the raw material for the preparation of 1, 2-butanediol and sec-butanol, and can be used to make the fungicide ethylconazole and the insecticide. It is mainly used for dehydrogenation to butadiene, and n-butanol can also be synthesized by water It is mainly used as standard gas for analytical instruments of petrochemical enterprises, atmospheric monitoring and scientific research and other fields One of the important basic chemical raw materials. The hydration of butene into sec-butanol can further produce methyl ethyl ketone, oxidative dehydrogenation to butadiene, catalytic oxidation to maleic anhydride and acetic acid, 1-butene self-polymerization can produce poly 1-butene, and ethylene copolymerization into Linear low density polyethylene.
production method	is mainly obtained by separation of C4 fraction. The butene content of C4 fractions from different sources varied. When separating butene isomers from C4 fraction, butadiene and isobutene are generally separated first, and then the remaining materials are rectified (or isomerized, adsorbed, etc.) to obtain 1-butene with purity higher than 99%. In some chemical applications (such as hydration to sec-butanol), the three isomers of butene can be used as raw materials, while butane and isobutane as inert substances do not affect the reaction. Therefore, in these situations, it is not necessary to separate one by one. In addition, there are other methods for the synthesis of butene. For example, ethylene dimerization can produce butene; n-butanol, isobutanol dehydration, or n-butane, isobutane dehydrogenation, etc. the content of 1-butene in C4 component obtained by tube furnace cracking and steam cracking method in naphtha cracking of petroleum fraction reaches about 35%, and 1-butene can be obtained by separating C4 fraction.
auto-ignition temperature	723 °F
DOT Classification	2.1 (Flammable gas)
toxic substance data	information provided by: pubchem.ncbi.nlm.nih.gov (external link)