be used for the alkylation of olefins with aromatics as in the production of
cumene (isopropylbenzene), ethylbenzene, etc. This review will concentrate
on refinery and olefin oligomer applications and will not discuss aromatic
alkylation applications.
History
The discovery of acid catalysis, and in particular the development of solid phosphoric acid (SPA) catalysts, is attributed to the pioneering work of Vladimir Ipatieff
at what was then called Universal Oil Products and is today known as UOP – a
Honeywell company. The first commercial unit for the production of octenes by the
dimerization of butenes came on stream in 1935. Introduction of this new gasoline
component contributed to the popularization of the automobile that had previously
been constrained by the availability of straight-run gasolines from petroleum crude
fractionation. In addition, the octenes obtained by butene dimerization had a much
higher octane number than naturally occurring straight-run gasolines. Several
hundred units were soon built to satisfy the growing demand for gasoline.
The dimerization and oligomerization of olefins over SPA catalysts is known as
the catalytic condensation process. This is still the dominant process for the
dimerization and oligomerization of olefins. Recent developments include acid
zeolite catalysts and, sulfonic acid resin catalysts.
The other type of condensation catalysts most often found in refinery applications for the production of gasoline components is organometallic catalysts developed by the Institut Franc ¸ais du Pe ´trole (IFP). They are used, in the dimerization of
propylene to isohexenes (Dimersol G process), or in the oligomerization of light
olefins from cracked gases (Dimersol E) or in the production of heptenes and
octenes from propylene and/or butenes (Dimersol X).
Because the production of olefin dimers and oligomers almost invariably produces
a blend of isomers and often also a lighter and a heavier fraction, the production of
these olefins for petrochemical applications cannot be easily segregated from their
application in gasoline and diesel fuel uses. However, it is usually the case that
catalysts can be tailored within certain limits so as to yield more branched
compounds (higher octane) for gasoline applications and less branched products
for petrochemical applications. Because the products from such processes always
have some branching, the quality of the products in the diesel range is somewhat poor
(low cetane numbers) and their use in diesel applications is not that extensive.
Catalytic Condensation Process
The catalytic condensation process was developed in the early 1930s as a means to
convert light gases produced by thermal cracking and thermal reforming into useful
products. R. E. Schaad and V. N. Ipatieff discovered that phosphoric acid mixed
with kieselguhr (an abundant naturally occurring siliceous diatomite mineral)
Olefin Condensation
459
cumene (isopropylbenzene), ethylbenzene, etc. This review will concentrate
on refinery and olefin oligomer applications and will not discuss aromatic
alkylation applications.
History
The discovery of acid catalysis, and in particular the development of solid phosphoric acid (SPA) catalysts, is attributed to the pioneering work of Vladimir Ipatieff
at what was then called Universal Oil Products and is today known as UOP – a
Honeywell company. The first commercial unit for the production of octenes by the
dimerization of butenes came on stream in 1935. Introduction of this new gasoline
component contributed to the popularization of the automobile that had previously
been constrained by the availability of straight-run gasolines from petroleum crude
fractionation. In addition, the octenes obtained by butene dimerization had a much
higher octane number than naturally occurring straight-run gasolines. Several
hundred units were soon built to satisfy the growing demand for gasoline.
The dimerization and oligomerization of olefins over SPA catalysts is known as
the catalytic condensation process. This is still the dominant process for the
dimerization and oligomerization of olefins. Recent developments include acid
zeolite catalysts and, sulfonic acid resin catalysts.
The other type of condensation catalysts most often found in refinery applications for the production of gasoline components is organometallic catalysts developed by the Institut Franc ¸ais du Pe ´trole (IFP). They are used, in the dimerization of
propylene to isohexenes (Dimersol G process), or in the oligomerization of light
olefins from cracked gases (Dimersol E) or in the production of heptenes and
octenes from propylene and/or butenes (Dimersol X).
Because the production of olefin dimers and oligomers almost invariably produces
a blend of isomers and often also a lighter and a heavier fraction, the production of
these olefins for petrochemical applications cannot be easily segregated from their
application in gasoline and diesel fuel uses. However, it is usually the case that
catalysts can be tailored within certain limits so as to yield more branched
compounds (higher octane) for gasoline applications and less branched products
for petrochemical applications. Because the products from such processes always
have some branching, the quality of the products in the diesel range is somewhat poor
(low cetane numbers) and their use in diesel applications is not that extensive.
Catalytic Condensation Process
The catalytic condensation process was developed in the early 1930s as a means to
convert light gases produced by thermal cracking and thermal reforming into useful
products. R. E. Schaad and V. N. Ipatieff discovered that phosphoric acid mixed
with kieselguhr (an abundant naturally occurring siliceous diatomite mineral)
Olefin Condensation
459