vacuum resids by reducing their sulfur and organometallic levels. Hydrotreaters
are designed for and run at a variety of conditions depending on many factors
such as feed type, desired cycle length, and expected quality of the products.
Until about 1980, hydrotreating was a licensed technology being offered by a
fairly large number of companies. From 1980 until the end of the last century,
hydrotreating catalysts were becoming more commoditized as the formulations
were less differentiated among the various suppliers. Many of the product
quality specifications are driven by environmental regulations, and these regulations are becoming more stringent every year. With the advent of ultra-lowsulfur fuel regulations ushering in the first decade of the twenty-first century,
however, it was required for hydrotreating research and development to deliver
quantum improvements in catalyst performance and process technology. This
was accomplished in the form of so-called Type II supported transition metal
sulfide (TMS) catalysts, unsupported/bulk TMS catalysts, improved bed grading
catalysts and stacking strategies, advanced catalyst loading techniques,
improved trickle-flow reactor internals designs, and more effective catalyst
activation methodologies.
Keywords
Hydrotreating • Hydrodesulfurization • Hydrodenitrogenation • Resid •
Gasoline • Distillate • Upgrading • Desulfurization • Denitrogenation
Introduction
Hydrotreating or catalytic hydrogen treating removes objectionable materials
from petroleum fractions by selectively reacting these materials with hydrogen
in a reactor at relatively high temperatures at moderate pressures. These objectionable materials include, but are not solely limited to, sulfur, nitrogen, olefins,
and aromatics. The lighter materials such as naphtha are generally treated for
subsequent processing in catalytic reforming units, and the heavier distillates,
ranging from jet fuels to heavy vacuum gas oils, are treated to meet strict product
quality specifications or for use as feedstocks elsewhere in the refinery.
Hydrotreating is also used for upgrading the quality of atmospheric and vacuum
resids by reducing their sulfur and organometallic levels. Many of the product
quality specifications are driven by environmental regulations that are becoming
more stringent every year. Hydrotreaters are designed for and run at a variety of
conditions depending on many factors such as feed type, desired cycle length, and
expected quality of the products; in general, they will operate at the following
ranges of conditions: LHSV, 0.2–8.0; H 2 circulation, 300–4,000 SCFB (50–675
Nm
3 /m
3 ); H 2 partial pressure, 200–2,000 psia (14–138 bara); and typical SOR
temperatures ranging between 500
F and 740
F (260–393
C), with the lower
limits representing minimum operating conditions for naphtha hydrotreating and
Hydrotreating in Petroleum Processing
363
are designed for and run at a variety of conditions depending on many factors
such as feed type, desired cycle length, and expected quality of the products.
Until about 1980, hydrotreating was a licensed technology being offered by a
fairly large number of companies. From 1980 until the end of the last century,
hydrotreating catalysts were becoming more commoditized as the formulations
were less differentiated among the various suppliers. Many of the product
quality specifications are driven by environmental regulations, and these regulations are becoming more stringent every year. With the advent of ultra-lowsulfur fuel regulations ushering in the first decade of the twenty-first century,
however, it was required for hydrotreating research and development to deliver
quantum improvements in catalyst performance and process technology. This
was accomplished in the form of so-called Type II supported transition metal
sulfide (TMS) catalysts, unsupported/bulk TMS catalysts, improved bed grading
catalysts and stacking strategies, advanced catalyst loading techniques,
improved trickle-flow reactor internals designs, and more effective catalyst
activation methodologies.
Keywords
Hydrotreating • Hydrodesulfurization • Hydrodenitrogenation • Resid •
Gasoline • Distillate • Upgrading • Desulfurization • Denitrogenation
Introduction
Hydrotreating or catalytic hydrogen treating removes objectionable materials
from petroleum fractions by selectively reacting these materials with hydrogen
in a reactor at relatively high temperatures at moderate pressures. These objectionable materials include, but are not solely limited to, sulfur, nitrogen, olefins,
and aromatics. The lighter materials such as naphtha are generally treated for
subsequent processing in catalytic reforming units, and the heavier distillates,
ranging from jet fuels to heavy vacuum gas oils, are treated to meet strict product
quality specifications or for use as feedstocks elsewhere in the refinery.
Hydrotreating is also used for upgrading the quality of atmospheric and vacuum
resids by reducing their sulfur and organometallic levels. Many of the product
quality specifications are driven by environmental regulations that are becoming
more stringent every year. Hydrotreaters are designed for and run at a variety of
conditions depending on many factors such as feed type, desired cycle length, and
expected quality of the products; in general, they will operate at the following
ranges of conditions: LHSV, 0.2–8.0; H 2 circulation, 300–4,000 SCFB (50–675
Nm
3 /m
3 ); H 2 partial pressure, 200–2,000 psia (14–138 bara); and typical SOR
temperatures ranging between 500
F and 740
F (260–393
C), with the lower
limits representing minimum operating conditions for naphtha hydrotreating and
Hydrotreating in Petroleum Processing
363