Recent Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453
Solid Catalyst Alkylation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453
Ionic Liquid Alkylation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
Abstract
Motor fuel alkylation in the petroleum refining industry refers to the acid-catalyzed
conversion of C 3 -C 5 olefins with isobutane into highly branched C5-C12
isoparaffins collectively called alkylate, a valuable gasoline blending component.
Alkylation reactions are catalyzed by liquid and solid acids. HF alkylation and
sulfuric acid alkylation are the most widely practiced commercial motor fuel
alkylation processes and are the focus of this section. In recent years, considerable
development effort has gone into solid acid catalysts and processes that mitigate
the hazards associated with HF and H2SO4. Several of these processes have been
offered commercially, but have not caught on because of high recycle isobutane
requirements and high capital costs associated with catalyst regeneration. A new
wave of ionic liquid catalysts is currently nearing commercialization.
Keywords
Alkylation • Motor fuel alkylation • Hydrofluoric acid (HF) alkylation • Sulfuric
acid alkylation • Solid catalyst alkylation • Ionic liquid alkylation
Introduction
Motor fuel alkylation in the petroleum refining industry refers to the acid-catalyzed
conversion of C 3 –C 5 olefins with isobutane into highly branched C 5 –C 12
isoparaffins collectively called alkylate, a valuable gasoline blending component.
A major constituent of alkylate is 2,2,4-trimethylpentane which is defined on the
octane scale by a value of 100.
Alkylation reactions are catalyzed by liquid and solid acids, including H 2 SO 4 ,
AlCl 3 -HCl, HF, HF-BF 3 , H 2 SO 4 -HSO 3 F (fluorosulfuric acid), trifluoromethanesulfonic acid, chlorided Pt-alumina, BF 3 on alumina, zeolites, and ion-exchange
resins. However, the catalysts and associated processes commercialized during
World War II for aviation gasoline, HF alkylation and sulfuric acid alkylation,
are the focus of this section as these remain the primary commercially practiced
motor fuel alkylation processes.
In recent years, considerable development effort has gone into catalysts and
processes that mitigate the hazards associated with HF and H 2 SO 4 . Several solid
catalyst processes (UOP Alkylene
TM
, CB&I/Albemarle/Neste Oy AlkyClean
TM ,
and Exelus ExSact
TM processes) have been offered commercially, but have not
caught on because of high recycle isobutane requirements and high capital costs
associated with catalyst regeneration. A new wave of alkylation processes based on
ionic liquid catalysts is currently nearing commercialization.
436
D.A. Nafis et al.
Solid Catalyst Alkylation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453
Ionic Liquid Alkylation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 454
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456
Abstract
Motor fuel alkylation in the petroleum refining industry refers to the acid-catalyzed
conversion of C 3 -C 5 olefins with isobutane into highly branched C5-C12
isoparaffins collectively called alkylate, a valuable gasoline blending component.
Alkylation reactions are catalyzed by liquid and solid acids. HF alkylation and
sulfuric acid alkylation are the most widely practiced commercial motor fuel
alkylation processes and are the focus of this section. In recent years, considerable
development effort has gone into solid acid catalysts and processes that mitigate
the hazards associated with HF and H2SO4. Several of these processes have been
offered commercially, but have not caught on because of high recycle isobutane
requirements and high capital costs associated with catalyst regeneration. A new
wave of ionic liquid catalysts is currently nearing commercialization.
Keywords
Alkylation • Motor fuel alkylation • Hydrofluoric acid (HF) alkylation • Sulfuric
acid alkylation • Solid catalyst alkylation • Ionic liquid alkylation
Introduction
Motor fuel alkylation in the petroleum refining industry refers to the acid-catalyzed
conversion of C 3 –C 5 olefins with isobutane into highly branched C 5 –C 12
isoparaffins collectively called alkylate, a valuable gasoline blending component.
A major constituent of alkylate is 2,2,4-trimethylpentane which is defined on the
octane scale by a value of 100.
Alkylation reactions are catalyzed by liquid and solid acids, including H 2 SO 4 ,
AlCl 3 -HCl, HF, HF-BF 3 , H 2 SO 4 -HSO 3 F (fluorosulfuric acid), trifluoromethanesulfonic acid, chlorided Pt-alumina, BF 3 on alumina, zeolites, and ion-exchange
resins. However, the catalysts and associated processes commercialized during
World War II for aviation gasoline, HF alkylation and sulfuric acid alkylation,
are the focus of this section as these remain the primary commercially practiced
motor fuel alkylation processes.
In recent years, considerable development effort has gone into catalysts and
processes that mitigate the hazards associated with HF and H 2 SO 4 . Several solid
catalyst processes (UOP Alkylene
TM
, CB&I/Albemarle/Neste Oy AlkyClean
TM ,
and Exelus ExSact
TM processes) have been offered commercially, but have not
caught on because of high recycle isobutane requirements and high capital costs
associated with catalyst regeneration. A new wave of alkylation processes based on
ionic liquid catalysts is currently nearing commercialization.
436
D.A. Nafis et al.