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Butadiene -IntroductionButadiene is a simple conjugated diene with

the formula C4H6.

Isomers: 1,-!utadiene and 1,"-!utadiene

It is an important industrial chemical used as amonomer in the production of s#nthetic ru!!er.

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$roduction- Extractionfrom C4 Hydrocarbons$roduced as a !#product of the steam crac%ing

process used to produce eth#lene and other ole&ns.

'liphatic h#drocar!osn mi(ed with steam, heated to

)er# high temperatures *often o)er + C, producesa comple( mi(ture of unsaturated h#drocar!ons,including !utadiene.

/ight feeds, such as ethane gi)e primaril# eth#lenewhen crac%ed, !ut hea)ier feeds fa)or the formation

of hea)ier ole&ns, !utadiene, and aromatich#drocar!ons.

Butadiene is t#picall# isolated from the other four-car!on h#drocar!ons produced in steam crac%ing !#e(traction, which it is then stripped !# distillation.

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From Dehydrogenation

of n-Butane'lso can !e produced !# the catal#tic

deh#drogenation of normal !utane.

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From EthanolButadiene is also produced from ethanol.

0ot competiti)e with steam crac%ing for

producing large )olumes of !utadiene, lowercapital costs ma%e production from ethanol a)ia!le option for smaller-capacit# plants.

 wo processes are in use.

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2ingle-step process, ethanol is con)erted to!utadiene, h#drogen, and water at 434C o)er an# of a )ariet# of metal o(idecatal#sts

2 CH3CH

2OH → CH

2=CH-CH=CH

2 + 2 H

2O + H

2

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two-step process, ethanol is o(idised toacetaldeh#de, which reacts with additionalethanol o)er a tantalum-promoted poroussilica catal#st at "3 C.

CH3CH

2OH + CH

3CHO → CH

2=CH-CH=CH

2 + 2 H

2O

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From ButenesB# catal#tic deh#drogenation of normal

!utenes. Howe)er this process is thought to!e no longer practiced commerciall#.

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Uses5ost !utadiene is pol#merised to produce

s#nthetic ru!!er.

2maller amounts of !utadiene are used toma%e the n#lon intermediate, adiponitrile.

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$ol#!utadieneIt is a s#nthetic ru!!er that is a pol#mer

formed from the pol#merisation process of themonomer 1,-!utadiene.

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Polymerization ofbutadiene' h#drocar!on diene molecule has two car!on-

car!on dou!le !onds*i. e. !etween two sets ofcar!on atoms. $ol#!utadiene can !e formed from

man# 1,-!utadiene monomers undergoing freeradical pol#merisation to ma%e a much longerpol#mer chain molecule.

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 he trans dou!le !onds allow the pol#mer chainto sta# rather straight, allowing sections ofpol#mer chains to line up against each other and

eecti)el# form microcr#stalline regions in thematerial.

 he cis dou!le !onds cause a !end in thepol#mer chain, pre)enting pol#mer chains fromlining up and forming cr#stalline regions andresulting in larger regions of amorphous pol#mer.5aterial with a su!stantial percentage of cis 

dou!le !ond con&gurations will gi)es 7e(i!leelastomer *ru!!er-li%e 8ualities.

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'ssignment0atural and 2#nthetic 9u!!ers*ump 1 dan

2#nthetic 9u!!er 5anufacturing $rocess *ump " dan 6

2#nthetic 9u!!er: 'pplications and ;ses *ump dan