June
2016
HYDROCARBON
ENGINEERING
84
Q&A
q
Explain why catalysts are so crucial to refining and
petrochemical operations.
The importance of catalysts to refining and petrochemical
processes is unparalleled. They are at the very heart of conversion
processes, especially heterogeneous catalysts. Catalysts lower
the activation barrier of reaction pathways, enabling reactions to
occur much faster and much more selectively than would ever be
possible without them. Catalysts are used to convert low value,
readily available, less desirable hydrocarbon products selectively
into higher value products that are in greater demand. Without
catalysts, there simply would not be a commercially viable
chemical industry.
The relatively recent application of catalysts to environmental
control has led to massive improvements in emissions. The
proliferation of environmental control catalysts has allowed the
tightening of emission regulations and permitted compliance at an
affordable price. In addition, state of the art environmental
catalysts allow refiners to improve their margins by processing
cheaper opportunity crudes.
q
How have catalysts changed since your company
began operating in the industry?
The introduction of the Clean Air Act really changed the refinery
landscape with respect to emissions. SO
X
control has become
ever more stringent in the US, and is catching up at a more
moderate pace in other areas. Controlled SO
X
emissions from
FCC units decreased from a few hundred ppm to 10 - 25 ppm in
the US, and typically less than 300 ppm in Europe. Emission of
other gases have followed suite: CO, NO
X
and lately HCN
received a lot of scrutiny. This required more effective control of
emissions, and additives have been chosen by many refiners as a
more cost effective control technology. Technologies have
further evolved, and more active and selective catalytic additives
have now become available. This has also affected fuel
specifications, resulting in deeper hydroprocessing and treating of
fuel components, increasing the need for hydrogen availability.
With the advent of shale oil in refineries, newmetal poisons
came into play. Potassium, calcium and especially iron poisoning
suddenly occurred frequently in many places. This required a new
approach. For example, in the fluid catalytic cracking (FCC) unit,
newmetal traps have been introduced to combat the negative
impact of these metals.
The need for hydrogen has also changed, as low natural gas
prices have pushed for ‘hydrogen addition’-based conversion
processes over the historical ‘carbon rejection’ processes. Refiners
have therefore needed to increase capacity to deal with the need
for increased hydrogen, whether for conversion processes or to
meet fuels regulations. This has led to a drive for catalyst
technologies that enable the refiner to 'do more with less'.
q
What are the main obstacles when developing a new
catalyst technology?
When developing new catalytic technologies, typically, the
challenge is striking the right balance between putting as much
catalytic activity in a catalyst and maintaining good physical
properties. New technologies frequently introduce newmaterials
with specific challenges for incorporation. Expansion of limits of
technology platforms and development of new technology
platforms and the corresponding manufacturing processes requires
substantial research and development (R&D) and engineering efforts.
q
What are the main applications for your company’s
catalysts or catalyst technologies within the refining
and petrochemical industries?
Johnson Matthey supplies a wide range of catalysts and absorbents
for refining and petrochemicals applications, including catalytic
additives for use in FCC units, catalysts for hydrogen plants and
selective hydrogenation catalysts. In addition, the company
supplies catalysts and adsorbents for the purification of gaseous
streams (C1-C2 streams), and lighter liquid petroleum streams (LPG,
olefins, naphtha and kerosene), as well as the upgrading of steam
cracking byproducts.
Johnson Matthey’s FCC and olefin catalysts fall into two major
benefit segments: Performance and Environmental. In the
Performance segment for FCC, the company includes catalysts that
boost activity and conversion, modify product selectivity towards
light olefins, improve gasoline octane, reduce bottoms yields and
protect the main catalyst system from the adverse effects of feed
contaminant metals such as vanadium and iron. For olefins, gains in
olefin yields downstream of steam crackers are achieved via use of
selective hydrogenation catalysts for conversion of unwanted
acetylenes and dienes to olefins. In the Environmental segment, the
company provides adsorbents for the removal of contaminants
such as hydrogen sulfide, mercury, chlorides and arsenic from
hydrocarbon streams. The chloride removal technology allows for
the use of chlorided catalyst platforms without impacting reliability
and safety in downstream units. Sulfur removal technologies are
employed to maintain optimal conversion of precious metal
catalysts, while removal of carbon oxides and sulfur in hydrogen
streams helps protect valuable catalysts. In addition to eliminating
such contaminants from final products, their removal also serves to
protect downstream processes from the detrimental effects of
these contaminants. In FCC applications the company provides
catalysts that, in-situ in the FCC unit, reduce SO
X
and NO
X
emissions, lower sulfur in gasoline and promote CO combustion in
the regenerator with minimumNO
X
penalty.
Johnson Matthey’s portfolio of hydrogen plant catalysts and
services focus on flow sheet functional simplicity such as
tri-functional purification catalyst and detailed steammethane
reformer monitoring using furnace imaging and process
temperature tracking technologies. This approach allows refiners to
achieve long term, reliable hydrogen production.
q
How has the fall in oil prices affected the downstream
catalyst industry over the past 12 months?
In 10 years time, refinery product slate is likely to be very different
from today. The drive for ever more fuel economical
transportation will reduce the demand for gasoline in the US and
Europe. Worldwide economic development will be a big driver for
petrochemicals. Improved process and catalyst technology will
allow for processing more refractory feedstocks, and targeting
lower fuel and improved petrochemical selectivities. In addition,
bio-feeds will form some part of refinery feeds, bringing their own
challenges.
q
What is the next 'big thing' in the downstream
catalyst market?
The ability to intensify hydrogen production through better heat
integration within the flow sheet, and the use of modular
structured reactors to make more hydrogen with less capital
equipment, will be a significant area of growth.
PAUL DIDDAMS AND KEN CHLAPIK,
JOHNSON MATTHEY PROCESS TECHNOLOGIES
