Products Description of Propylene
Propylene is the second-simplest olefin, featuring the structural formula CH₂=CHCH₃. It stands as one of the most critical organic chemical feedstocks, surpassed only by ethylene and benzene. It is generally isolated from gas streams produced in thermal cracking and catalytic cracking, and is also generated as a by-product during ethylene manufacturing via light oil cracking.
An unsaturated carbon-carbon double bond exists in its molecular framework, which allows propylene to participate in addition reactions with hydrogen, halogens and hydrogen halides, alongside addition polymerization. It functions as an essential starting material for making acrylonitrile, polypropylene, ethylene-propylene rubber, propylene oxide, acetone and various synthetic resins, synthetic rubbers, synthetic fibers and plastics.
Melting point | -185 °C(lit.) |
Boiling point | -47.7 °C(lit.) |
Density | 1.49 |
Vapor density | 1.48 (vs air) |
Vapor pressure | 15.4 atm (37.7 °C) |
Refractive index | 1.3567 |
Flash point | -108°C |
Acidity coefficient (pKa) | 43(at 25°C) |
Form | colorless gas |
Explosion limits | 11.10% |
Odor threshold | 13ppm |
Water solubility | 0.33g/L(25 °C) |
Thermal conductivity | 0.11 W/(m-K) |
Freezing point | -185.25℃ |
Merck | 137,941 |
BRN | 1696878 |
Henry's Law Con stant | 5.6x10-5 mol/(m3Pa) at 25℃, Plyasunov and Shock (2000) |
Dielectric constant | 1.9 (20℃) |
Stability | Stable. Highly flammable. Easily forms explosive mixtures with air. Incompatible with strong oxidizers, strong acids, and halogens. |
InChI | 1S/C3H6/c1-3-2/h3H,1H2,2H3 |
InChIKey | QQONPFPTGQHPMA-UHFFFAOYSA-N |
SMILES | CC=C |
LogP | 1.77 at 20℃ |
Product Application of Propylene
Propylene is an indispensable building block for the chemical industry and acts as a core starting material to make a great variety of downstream chemical products. Gas-phase oxidation of propylene generates acrolein, an intermediate for preparing acrylic acid, allyl alcohol, glyceraldehyde, glycolaldehyde, plus methionine, a prominent additive applied in food and animal feed.
Ammoxidation of propylene affords acrylonitrile, a crucial precursor for synthetic fibers, synthetic elastomers and plastic commodities. Propylene chlorination forms allyl chloride, which may be processed onward into allyl alcohol, propylene dichlorohydrin, chloropropionitrile and other intermediates for glycerol, epoxy resins, epichlorohydrin rubber and surfactants.
Propylene undergoes alkylation to form cumene, the main precursor for phenol synthesis, alongside acetone as a marketable by-product. Hydroformylation of propylene yields n-butyraldehyde and isobutyraldehyde; these are vital intermediates for plasticizers, colorants, solvents, agrochemicals and other organic chemical goods.
Besides the above routes, propylene hydration yields isopropanol, which can be further processed into acetone, isopropylamine and isopropyl ester derivatives. Propylene is also amenable to dimerization, trimerization, polymerization and tetramerization to deliver high-value outputs including ethylene, propylene trimers, polypropylene and dodecene. Dodecene, in particular, is a key intermediate for surfactant manufacturing.
