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Ethylene (IUPAC name: ethene) is a hydrocarbon which has the formula C 2 H 4 or H 2 C=CH 2.It is a colourless, flammable gas with a faint "sweet and musky" odour when pure. [7] It is the simplest alkene (a hydrocarbon with carbon–carbon double bonds).
The chief use of ethane is the production of ethylene (ethene) by steam cracking. Steam cracking of ethane is fairly selective for ethylene, while the steam cracking of heavier hydrocarbons yields a product mixture poorer in ethylene and richer in heavier alkenes (olefins), such as propene (propylene) and butadiene, and in aromatic hydrocarbons.
There is a difference in the mixing ratio, depending on whether it is ethylene glycol or propylene glycol. For ethylene glycol, the mixing ratios are typically 30/70 and 35/65, whereas the propylene glycol mixing ratios are typically 35/65 and 40/60. It is important that the mixture be frost-proof at the lowest operating temperature. [24]
The reaction usually involves strong acid as catalyst. [19] The first step in hydration often involves formation of a carbocation. The net result of the reaction will be an alcohol. The reaction equation for hydration of ethylene is: H 2 C=CH 2 + H 2 O→ H 3 C-CH 2 OH Example of hydrohalogenation: addition of HBr to an alkene
It is the ethylene (IUPAC name: ethene) molecule (H 2 C=CH 2) with one fewer hydrogen atom. The name is also used for any compound containing that group, namely R−CH=CH 2 where R is any other group of atoms. An industrially important example is vinyl chloride, precursor to PVC, [3] a plastic commonly known as vinyl.
This reaction, the Williamson ether synthesis, involves treatment of a parent alcohol with a strong base to form the alkoxide, followed by addition of an appropriate aliphatic compound bearing a suitable leaving group (R–X). Although popular in textbooks, the method is usually impractical on scale because it cogenerates significant waste.
The monomers are terephthalic acid (HOOC—C 6 H 4 —COOH) and ethylene glycol (HO—CH 2 —CH 2 —OH) but the repeating unit is —OC—C 6 H 4 —COO—CH 2 —CH 2 —O—, which corresponds to the combination of the two monomers with the loss of two water molecules.
The main differences between each of them concerns the catalyst employed, design of the reactor and strategies to achieve higher conversion rates. [1] Olefins are useful precursors to myriad products. Steam cracking is the core technology that supports the largest scale chemical processes, i.e. ethylene and propylene. [2]