Page 162 - Chemical and process design handbook

Speight_Part II_B 11/7/01 3:11 PM Page 2.103

BUTENE-1

The steam cracking of naphtha and catalytic cracking in the refinery pro-
duce the C stream, which includes butane, 1-butene (butylene), cis- and
4
trans-2-butene, isobutylene, and butadiene.
C H → CH CH CH CH=CH
n 2n+2 3 2 2 2
Extracting the isobutylene with sulfuric acid and distilling the 1-butene
away from butane and butadiene is used for separation of the 1-butene. It is
also made by Ziegler (or non-Ziegler) oligomerization of ethylene (Fig. 1).

1-butene is used as a comonomer to make polyethylene and is used to
make valeraldehyde (pentanal) by the oxo process, polybutene-l, and buty-
lene oxide.

Catalyst
preparation
and storage
n-butene
Ethylene recycle

Liquid phase reactor Distillation Fractionator
Ethylene

C 6 +
Catalyst Heavy ends and
removal spent catalyst

FIGURE 1 Manufacture of butene-1 (n-butene) by dimerization of ethylene.

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