petrochemical industry (Huebner 1999), more severe conditions are employed to
increase the conversion of the naphtha feed to maximize the production of aromatics. In both cases, hydrogen and other light hydrocarbons are produced in the
reactions as by-products. In some applications, hydrogen has a high value and is a
desired product from the process.
History
The need to upgrade naphthas for transportation fuels was recognized early in the
twentieth century. Thermal processes were initially used, but catalytic processes
introduced in the 1940s offered better yields and higher octanes. The first catalysts
were based on supported molybdenum oxide, but were soon replaced by platinumcontaining catalysts. The first platinum-based reforming process, UOP’s
Platforming™ process, came on-stream in 1949 at Old Dutch Refining in Muskegon, Michigan, USA. Since the first Platforming unit was commercialized, innovations and advances have been made continuously, including process flow schemes
and parameter optimization, catalyst formulations, equipment design, and maximization of reformate and hydrogen yields. The need to increase yields and octane led
to lower pressure, higher severity operations. Higher severity generally refers to
conditions such as higher temperature that lead to higher naphtha conversion. This
also results in increased catalyst coking, faster deactivation rates, decreasing yields,
and shorter catalyst lives.
The first catalytic reforming units were designed as semiregenerative (SR) or
fixed-bed units with three to four reactors in series, using Pt/alumina catalysts.
SR reforming units are periodically shut down for catalyst regeneration. A cycle
may run from 6 to 36 months, typically about 1 year. Regeneration involves burning
off coke and reconditioning the catalyst’s active metals. To minimize catalyst
coking and deactivation, these older units were operated at high pressures in the
range of 2,760–3,450 kPa (400–500 psig).
Catalytic reforming processes were improved by the introduction of bimetallic
catalysts. These catalysts allowed lower pressure, high severity operations at about
1,380–2,070 kPa (200–300 psig) and could achieve a 95–98 research octane
number (RON) with typical cycle lengths of 1 year between catalyst regenerations.
The cyclic reforming process was developed in the 1960s by several major oil
companies such as Esso (Powerforming
TM ), Standard Oil (Ultraforming
TM ), and
Shell. These processes allow operation at increased severity by significantly
decreasing the time between regenerations. Cyclic reformers typically employ
five fixed-bed reactors in which each can be isolated from the main process flow,
regenerated, and put back into service without shutting down the unit and losing
production. Each reactor is regenerated every 3–30 days depending on severity,
feed type, and reactor position. The average reactor pressures are approximately
1,380 kPa (200 psig) producing reformates with research octane numbers near 100.
A significant innovation addressing catalyst deactivation and on-stream efficiency was the commercialization of the Platforming™ process with continuous
Catalytic Reforming in Petroleum Processing
231
increase the conversion of the naphtha feed to maximize the production of aromatics. In both cases, hydrogen and other light hydrocarbons are produced in the
reactions as by-products. In some applications, hydrogen has a high value and is a
desired product from the process.
History
The need to upgrade naphthas for transportation fuels was recognized early in the
twentieth century. Thermal processes were initially used, but catalytic processes
introduced in the 1940s offered better yields and higher octanes. The first catalysts
were based on supported molybdenum oxide, but were soon replaced by platinumcontaining catalysts. The first platinum-based reforming process, UOP’s
Platforming™ process, came on-stream in 1949 at Old Dutch Refining in Muskegon, Michigan, USA. Since the first Platforming unit was commercialized, innovations and advances have been made continuously, including process flow schemes
and parameter optimization, catalyst formulations, equipment design, and maximization of reformate and hydrogen yields. The need to increase yields and octane led
to lower pressure, higher severity operations. Higher severity generally refers to
conditions such as higher temperature that lead to higher naphtha conversion. This
also results in increased catalyst coking, faster deactivation rates, decreasing yields,
and shorter catalyst lives.
The first catalytic reforming units were designed as semiregenerative (SR) or
fixed-bed units with three to four reactors in series, using Pt/alumina catalysts.
SR reforming units are periodically shut down for catalyst regeneration. A cycle
may run from 6 to 36 months, typically about 1 year. Regeneration involves burning
off coke and reconditioning the catalyst’s active metals. To minimize catalyst
coking and deactivation, these older units were operated at high pressures in the
range of 2,760–3,450 kPa (400–500 psig).
Catalytic reforming processes were improved by the introduction of bimetallic
catalysts. These catalysts allowed lower pressure, high severity operations at about
1,380–2,070 kPa (200–300 psig) and could achieve a 95–98 research octane
number (RON) with typical cycle lengths of 1 year between catalyst regenerations.
The cyclic reforming process was developed in the 1960s by several major oil
companies such as Esso (Powerforming
TM ), Standard Oil (Ultraforming
TM ), and
Shell. These processes allow operation at increased severity by significantly
decreasing the time between regenerations. Cyclic reformers typically employ
five fixed-bed reactors in which each can be isolated from the main process flow,
regenerated, and put back into service without shutting down the unit and losing
production. Each reactor is regenerated every 3–30 days depending on severity,
feed type, and reactor position. The average reactor pressures are approximately
1,380 kPa (200 psig) producing reformates with research octane numbers near 100.
A significant innovation addressing catalyst deactivation and on-stream efficiency was the commercialization of the Platforming™ process with continuous
Catalytic Reforming in Petroleum Processing
231