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Purification catalysts and absorbents
Katalco
JM_960_869 bPurification Broch 27/4/06 11:42 am Page 2
Information contained in this publication or as otherwise supplied to Users is believed to be accurate and correct at time of
going to press, and is given in good faith, but it is for the User to satisfy itself of the suitability of the product for its own particular
purpose. Johnson Matthey plc (JM) gives no warranty as to the fitness of the Product for any particular purpose and any implied
warranty or condition (statutory or otherwise) is excluded except to the extend that exclusion is prevented by law. JM accepts no
liability for loss or damage (other than that arising from death or personal injury caused by JM’s negligence or by a defective
Product, if proved), resulting from reliance on this information. Nothing here in should be considered to provide freedom to
operate under any Patent.
JM_960_869 bPurification Broch 27/4/06 11:42 am Page 3
Contents
Page
Introduction 2
Case studies 3
KATALCOJM PERFORMANCE adds value to your plant 5
Advantages of choosing Johnson Matthey purification catalysts and absorbents 6
Additional capability with KATALCOJM PERFORMANCE 9
Catalyst selector 12
Catalyst characteristics 13
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Feedstock purification is a key unit operation in any
synthesis gas plant which employs steam reforming
technology. Its importance is often overlooked, however, and
the consequences of not installing the correct catalysts and
absorbents, or of not monitoring performance appropriately,
can have dramatic and costly consequences for downstream
catalysts. The key catalysts in synthesis gas plants that may
be poisoned by trace components in the feed gas are
pre-reforming, steam reforming, low temperature shift and
methanol synthesis.
The most common catalyst poisons experienced are
sulphur compounds present as hydrogen sulphide, COS,
mercaptans, organic sulphides and disulphides, and
thiophenes. Occasionally halogen compounds are present,
usually as hydrogen chloride, but sometimes as organic
chlorides. Some plants also experience feedstocks with
more unusual poisons such as mercury, arsenic and other
metallic species.
Very severe poisoning will lead to significant costs. For
example, with severe sulphur poisoning incidents the
affected steam reforming catalyst may need to be replaced.
In addition to downtime, possibly measured in weeks, the
catalyst cost must be added. The financial cost of such
incidents varies depending on the size and type of the plant,
however, for large scale plants (e.g. 100 MMSCFD hydrogen;
2,000 mtpd ammonia; 2,500 mtpd methanol) each day of
lost production costs in the order of US$ 350,000 and
typical catalyst replacement cost is in the order of
US$ 750,000. In comparison, the catalyst and absorbent
cost in a typical purification system for plants of a similar
scale is around US$ 240,000. Thus, the provision and
timely replacement of these materials is a comparatively
small investment compared to the potential costs of
poisoning the downstream catalysts.
IntroductionIn plants with a pre-reformer, sulphur removal is critical to
successful operation of the catalyst. A serious sulphur
incident usually means immediate catalyst replacement is
required. In addition to downtime, the replacement catalyst
cost will be significant, approaching that for a steam reformer
charge depending on the pre-reformer bed volume.
Both sulphur and chlorides severely affect both low
temperature shift (LTS) and methanol synthesis catalysts.
These copper-based catalysts scavenge both sulphur and
chlorides very effectively and are poisoned as a result. For a
2,000 mtpd ammonia plant, the cost in terms of lost LTS
life can be of the order of US$ 500,000 per year plus the
incremental production loss as water gas shift efficiency
decreases. The effect on methanol synthesis catalysts have
similar financial consequences.
In comparison, the total cost of the catalysts and absorbents
in the purification system is significantly less than the cost of
the problems that can occur if the purification catalysts are
not well maintained.
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Case study – PURASPECJM™ ultrapurificationimproves reformer catalyst life
A Western European HyCO plant has operated for a
number of years with a two year turn-around cycle.
Historically at each turn-around, the operator replaced the
steam reforming catalyst in order to have confidence that
the plant would operate reliably and efficiently enough in
the next two year cycle. The steam reformer feedstock is a
methane rich natural gas and the steam reforming
conditions are relatively severe since this is a HyCO plant.
PURASPECJM 2084 was installed in the purification section
to reduce the level of trace sulphur slipping to the steam
reformer. Over the two year cycle following the installation
of the PURASPECJM 2084, the operator observed a much
slower rate of activity decline in the steam reforming
catalyst. The plant operating conditions for this cycle were
the same as for previous cycles, and it was concluded that
the improved performance was a result of the use of the
ultra-purification absorbent. The operator therefore had the
confidence that the installed steam reformer catalyst would
last for a second two year operating cycle.
The benefit to the operator was the saving in terms of steam
reformer catalyst purchase and replacement costs and an
improved efficiency of operation during the initial two year
operating cycle. This saved the plant US$ 400,000 in
catalyst replacement costs.
Case study – Correct sampling for poisonseliminates plant operating problems
Sampling and testing for sulphur is not a simple task and
there are many issues that have to be addressed. One plant
suffered severe hot banding leading to regular steam outs
and a loss of tube life. Sampling of the feedstock at the exit
of the desulphurization system detected no sulphur and this
was therefore ruled out as the cause of the problem. A
lengthy investigation was conducted to identify the root
cause of the problem but no other potential causes of the
hot banding were found.
The desulphurization system was then re-investigated.
The first issue highlighted was that the sample lines were
relatively long and the metal utilized for the sample lines
would absorb sulphur. The sample lines were therefore
redesigned, reducing the length significantly and using a
metallurgy that would not absorb sulphur. The sample
bombs were also replaced with a superior metallurgy.
Subsequent analysis of the feed gas established that
significant levels of sulphur were passing through the
desulphurization system to the steam reformer.
The installed catalysts and absorbents were then replaced
with KATALCOJM products and the steam reformer was
steamed a final time to remove the sulphur from the
catalyst. As a result of this the tube appearance has now
improved and the tube wall temperatures have returned to
the normal value.
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Case study – KATALCOJM PERFORMANCEverifies plant modifications to deliverperformance
Through KATALCOJM PERFORMANCE Johnson Matthey
Catalysts delivers a range of services that ensures improved
performance of your plant. An example of how this has
benefited one of our customers is outlined below.
As part of a project to eliminate an operational problem, the
plant were proposing to change the outlet temperature from
the feed pre-heat coil upstream of the hydrodesulphurization
bed. The plant operator was concerned that such a change
could lead to operating problems within the coil and
potentially lead to hydrocarbon cracking.
Johnson Matthey was requested to review the proposed
modification in order to determine if there would be any
problems. Our process engineers used Aspen Technology’s
FIHR simulation package to model the performance of the
existing coil. The initial FIHR model used rationalised plant
data in order to calibrate the model and ensure that it was
accurate. The FIHR model was then used to predict the
performance of the coil with the modifications included. The
predicted internal metal skin temperatures were used in
Johnson Matthey’s in-house programs to determine if
hydrocarbon cracking would occur.
This showed that performance of the coil would be acceptable
and that hydrocarbon cracking would not be an issue.
The plant has now been modified and, after a significant
period of operation, has not seen any pressure drop increase
over the hydrodesulphurization bed, confirming that the
model prediction of no carbon formation was correct.
Case study – TRACERCO ZnO scanreduces turnaround costs
A Western European ammonia producer intended to
replace its zinc oxide bed during a planned shut down as it
had been installed for some time. The operator however
had no idea how much of the absorbent had been used.
Prior to the shut down, a TRACERCO MAXIMIZER™ scan was
performed on the zinc oxide vessel. The scan determined
that the boundary between reacted and unreacted zinc
oxide appeared to be approximately 40% down the bed,
indicating that at least 50% of the bed was unreacted ZnO.
Following the scan the vessel was discharged with samples
of the absorbent taken at intervals down the bed depth. The
samples were analysed in the bed and confirmed that from
50% onwards, the bed was unreacted ZnO. The operator
only changed out 50% of the absorbent, which saved them
US$ 190,000 in turn-around costs.
Sulphur absorbent profile results of scanning
zinc oxide vessel
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Impact of Ultrapurification Reformer Activity
and the poisoning problem cannot be resolved, and plant
rate has to be reduced, there will be a loss of production,
which has been proven to cost the plant operator
US$ 6.3 million per year.
By installing ultra-purification upstream of a pre-reformer,
the pre-reformer life can be extended greatly and this can
be worth US$ 250,000 in reduced pre-reformer catalyst
replacement costs.
Chlorides are very difficult to remove from a steam reformer
during a steam out and in many cases the primary reformer
catalyst will have to be changed out. The total cost for a two
week shut-down to replace the catalyst is estimated to be
US$ 2.6 million per week, including shut-down, catalyst and
lost production costs.
KATALCOJM PERFORMANCE adds value to your plantOne plant suffered from a poorly operating purification
system that slipped sulphur to the primary reformer. In
order to continue operating the plant shut down regularly
to steam the primary reformer and remove the sulphur.
Replacing the purification system with KATALCOJM
purification products eradicated the problem saving the
plant operator an estimated US$ 2,100,000 each year.
PURASPECJM ultra-purification absorbent was installed
on a plant and resulted in doubled the life of the steam
reforming catalyst. This saved the customer over
US$ 400,000 in replacement catalyst costs.
Following a TRACERCO MAXIMIZER scan of a zinc oxide
vessel, the plant operators determined that it was only
necessary to change 50% of the bed. This gave a saving of
US$ 190,000 in replacement zinc oxide costs.
A number of plants have removed their hydrodesulphurization
catalysts for a variety of reasons. Of these, one plant found
that the steam reformer catalyst soon became poisoned
and the plant was forced to conduct regular steam outs
whilst they investigated the root cause of the problem. By
the time it was found that the feed to the plant contained
significant levels of organic sulphur, the plant had conducted
three steam outs costing US$ 450,000 in lost production.
During the same period, the reformer tubes were run at
higher than normal temperatures and this reduced the
tube life which increased the tube replacement costs by
US$ 300,000.
The additional sulphur absorption capacity of KATALCOJM 32-5
over competitive materials allows for increased run lengths
and therefore a reduction in absorbent costs. This is worth
US$ 50,000 per charge of zinc oxide plus the cost of
having to conduct the absorbent change out.
The cost of poisoning a steam reforming catalyst charge is
significantly greater than the cost to install, monitor and
operate a good purification system. Operating a plant with a
poisoned steam reforming catalyst leads to hot bands which
in turn increase the tube wall temperature. This increased
temperature reduces the life of the steam reformer tubes,
increasing the tube replacement costs by US$ 250,000. In
such circumstances, if regular steam outs are not conducted
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• Reliable operation
Dependable delivery of purified feed gas into the
downstream process, even during upset conditions,
ensures that the downstream catalysts are able to deliver
high conversion and maintain long operating lives.
• Stable pressure drop
High strength of catalysts ensures that even if pressure
drop starts to build up due to deposition of foulants on
top of the bed, catalysts are strong enough to withstand
the hydraulic forces applied.
Organic sulphur removal - HDS
Effective breakdown of organic sulphur compounds in the
feedstock is essential so that the H2S produced can be
removed downstream. In addition, the catalyst must break
down any organo-chlorine compounds and hydrogenate
olefins to a level acceptable for the steam reformer.
The KATALCOJM HDS catalysts are available in both cobalt
molybdenum (CoMo), KATALCOJM 41-6T, and nickel
molybdenum (NiMo), KATALCOJM 61-1T, formulations to suit
the combination of reactions for particular plant situations.
KATALCOJM 41-6T and KATALCOJM 61-1T are manufactured
with an optimized loading of active components to give high
volumetric activity and ensure high selectivity for
hydrogenation. The high activity allows the catalyst to cope
with increased feed rates, upsets and impurities which would
otherwise lead to slippage of un-reacted organic sulphur
compounds. The products also remove trace levels of
arsenic compounds and, in the case of certain heavy
naphtha feeds, traces of most metallic species.
The trilobe shape offers a lower pressure drop than standard
extrudates. In addition, the strength and attrition resistance
are improved to minimize breakage during loading and
operation, so that a low pressure drop can be maintained
throughout the catalyst life.
The purification section in a syngas plant is usually designed
in two to four stages depending on the plant design
requirements. In the hydrodesulphurization (HDS) stage, the
organic sulphur compounds are catalytically converted to
liberate sulphur as hydrogen sulphide with analogous
reaction of any organo-chlorine compounds. The HDS
catalyst also acts as a trapping agent for many of the less
usual poisons if these are present. Where necessary, an
absorbent is next installed to remove hydrogen chloride by
chemical reaction. The third stage is removal of hydrogen
sulphide using absorbents based on zinc oxide, which reacts
to form zinc sulphide. In certain plants, a fourth ultra-
purification stage is used to reduce the sulphur content of
the feed to extremely low levels.
Operational benefits
All Johnson Matthey purification catalysts offer a number of
operational benefits:
• Flexible operating conditions
KATALCOJM and PURASPECJM catalysts and absorbents
can be operated over a wide range of temperatures,
pressures and feedstocks. For example, HDS catalysts and
zinc oxide absorbents have operated continuously in
systems designed to run at temperatures as low as 250°C
(482°F) and pressure as high as 50 bar (725 psi). Our
purification catalysts are proven to be effective on a wide
range of feedstocks, from light natural gases, through
LPG’s, light naphthas to heavy naphthas containing 20%
aromatics.
• Long lives
High activity and excellent absorption capacity mean that,
with appropriate product selection, the purification
catalysts lives will be maximized while extending the life of
the downstream catalysts.
Advantages of choosing Johnson Matthey purification
catalysts and absorbents
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Desulphurization – zinc oxide
The performance of zinc oxide based H2S removal
absorbents is strongly influenced by the formulation of the
product. Usage of a very high purity zinc oxide (say 99+ wt%)
of the highest possible density would place the most
theoretical sulphur capacity in a reactor but would not
provide the best performance in practice. This is due to the
very low porosity and huge mass transfer zone of such a
product, resulting in premature breakthrough of sulphur to
downstream catalyst. Products must be formulated with the
highest possible porosity to facilitate the reaction between
the H2S and zinc oxide to maximize the rate and extent of
sulphur absorption. In turn, this leads to a tight mass
transfer zone and maximizes sulphur absorption capacity
and therefore the absorbent life for a given installed volume.
KATALCOJM 32-series absorbents combine specific zinc
oxide phases with a binder using granulation technology to
produce spheres with the required combination of
properties to provide excellent sulphur absorption capacity
in the differing designs for zinc oxide beds.
KATALCOJM 32-4 is a higher porosity material which has a
particularly sharp sulphur profile. This ensures that
conversion of the zinc oxide in the bed, and therefore
sulphur pick up, is maximized before sulphur breakthrough
occurs. KATALCOJM 32-4 is the product of choice for plants
which are designed with a single sulphur removal bed.
KATALCOJM 32-5 is a higher density material and provides
maximum saturation pick-up. This makes it ideal material for
two bed series lead/lag system designs. The lag bed provides
protection of the downstream process while the sulphur
level exiting the lead bed is allowed to increase before
replacement of the spent bed is required. This allows the
higher saturation capacity of the KATALCOJM 32-5 to be
fully utilized.
Chloride removal
Where chloride species are present in hydrocarbon feeds,
the level is usually low. After these species are converted to
hydrogen chloride over the HDS catalyst, they are present as
hydrogen chloride and must be removed upstream of the zinc
oxide absorbent. Zinc oxide reacts with chlorides to form zinc
chloride and this adversely affects the porosity of the zinc oxide
bed. This in turn impairs its sulphur absorption capacity and
reduces the absorbent life. In addition, at normal operating
temperatures, zinc chloride may migrate causing potential
poisoning, corrosion and metallurgy issues downstream.
The low chloride level means that the volume of absorbent
required is usually small as long as it has a good chloride
capacity. Consequently, it is usually included in the same
reactor(s) as the zinc oxide as a thin top layer. The low contact
time necessitates a fast efficient reaction between the HCl and
its absorbent to effectively remove chloride to extremely low
levels needed for protection of downstream catalysts.
KATALCOJM 59-3 is formulated to provide fast reaction times
and to have a high capacity for chloride removal. It contains
a highly reactive alkali phase, sodium aluminate, dispersed
on an alumina substrate. The gas phase reaction between
HCl and sodium aluminate locks up the chloride as sodium
chloride. Where higher chloride levels are encountered, the
high reactivity of KATALCOJM 59-3 allows spikes of HCl to be
removed effectively without compromising plant operation.
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PURASPECJM for unusual purificationrequirements
In addition to our standard products, Johnson Matthey
Catalysts offer a number of PURASPECJM catalysts and
absorbents for difficult or unusual purification duties.
Arsenic as arsine or organo-arsine can be found
occasionally in natural gas and LPG cuts. Although the HDS
catalyst will remove these, the arsenic compounds act as a
poison. An alternative approach is to treat the hydrocarbon
upstream using a dedicated arsenic guard bed. For gas
phase, we recommend PURASPECJM 1152 whereas, for
liquid phase LPG, it is PURASPECJM 5152.
Mercury and organo-mercury compounds are being
reported more frequently in various hydrocarbon sources in
part due to improved analytical methods and in part due to
increased processing of mercury containing sources.
Mercury has been found in the ammonia synthesis section
of certain plants implying that it passes through the entire
flowsheet. Thus, if mercury is identified in the feed,
upstream treatment should be considered. For gas phase,
we recommend PURASPECJM 1156 whereas, for liquid phase
naphtha, it is PURASPECJM 6156. These products are able to
remove mercury to below ppb levels.
For various reasons, in certain flowsheets it is necessary to
run the purification section cooler than usual. In these cases,
special HDS catalyst and zinc oxide absorbents are preferred
which are optimized for the lower temperature. Where the
HDS reactor must operate at an inlet temperature below
300°C (572°F), KATALCOJM 61-2T is the preferred product.
This has a higher active metal level to initiate the reaction at a.cooler temperature. For H2S removal below 250°C (482°F),
PURASPECJM 2020 is preferred to KATALCOJM 32-series.
Ultra-purification
Ultra-purification or sulphur polishing absorbents are
appropriate in some specific plant circumstances where the
downstream catalysts are more susceptible to poisoning
even by low sulphur levels. Analysis indicates that the total
sulphur level exiting the zinc oxide absorbent is typically a
few tens of ppb comprising of H2S, COS and traces of
organo-sulphur species. The precise levels and mix vary as a
function of the feedstock composition, operating conditions
and effectiveness of the purification products installed. This
low level of sulphur may still have a negative impact, for
example, if the plant has a pre-reformer or a highly stressed
top fired reformer since these are both particularly sensitive
to sulphur poisoning. Thus, to maximize the life of these
absorbents, Johnson Matthey Catalysts recommends the use
of an ultra-purification catalyst, PURASPECJM 2084, as a
final stage in the purification system. This reacts with and
removes most of the trace sulphur compounds typically to
levels below 10 ppbv.
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Since both of these methods have drawbacks, Johnson
Matthey recommends supplementing sample analysis with the
TRACERCO MAXIMIZER zinc oxide bed scanning technique.
This is a proven, highly effective method for determining zinc
oxide usage and prediction of remnant bed life. It uses an
external scanning device and so there is no need for a plant
shut down. Results are available almost instantly.
This measurement uses a radioactive neutron source and a
neutron detector to measure neutron back-scattering and to
detect density differentials in the material inside the vessel.
As zinc sulphide is more dense than zinc oxide, there is
greater neutron absorption through zinc sulphide than zinc
oxide. This difference is measured and therefore accurately
determines the position of the interface.
This service is available through the Johnson Matthey
TRACERCO business.
Monitoring consumption of ZnO
Proper monitoring to ensure optimum utilization of a zinc
oxide charge is a challenging task. One method of
calculating zinc oxide usage is to measure inlet and exit
sulphur levels together with gas flow rate to calculate the
amount of sulphur removed. This value can be compared to
the expected sulphur capacity of the bed to estimate the
proportion of the zinc oxide consumed and also to predict
the remaining life for the bed. In plants with frequent on line
low level sulphur analysis combined with flow monitoring,
this calculation may be reasonably accurate. Many plants,
however, rely on analysis of gas samples taken from the
process at intervals, sometimes with several days between
samples. This procedure reduces the calculation accuracy
and increases the risk of sulphur breakthrough.
Sampling of inlet gas sulphur content at intervals may not
identify variation and spikes in the sulphur content of the feed.
For example, natural gas may become sour as the wells
approach exhaustion. Alternatively, natural gas may be taken
from a number of fields with variation in sulphur content and
mixed in varying proportions. In such cases, samples analysed
at intervals are unlikely to detect variation accurately. Thus, the
calculation of the inlet sulphur will be inaccurate.
Sampling of exit gas sulphur content is essential to
determine that the downstream catalysts are protected. If
sampling at intervals, however, it is possible that the critical
point when breakthrough occurs may be missed. Also, exit
gas sampling provides no direct information on the extent to
which the zinc oxide bed has been consumed or of impending
sulphur breakthrough. Only a small proportion of plants
have gas sample points down the bed and even then the
gas sample may not be representative if the sample point is
damaged or blocked.
Additional capability with KATALCOJM PERFORMANCE
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Sulphur sampling system design
Sulphur sampling and testing is a highly complex area.
Johnson Matthey Catalysts has a detailed knowledge of the
process and mechanical design of the sampling system and
also an extensive understanding of the analysis
methodologies. Using this, Johnson Matthey Catalysts can
review sampling and testing systems to identify improvement
opportunities. This will ensure that any sulphur that does slip
from the desulphurization will be detected before the impact
on the downstream equipment and catalysts is significant.
Catalyst probe
The TRACERCO catalyst probe allows insertion of a sample
of catalyst into a process stream. By selecting an
appropriate absorbent/catalyst it is possible to check for the
presence of poisons within a stream and thereby determine
the root cause of downstream problems. Intermittent ‘slugs’
of poisons can be identified using the sample probe
whereas such random levels of poisons will be almost
impossible to identify with spot sampling of the process
stream, but yet can cause severe plant problems.
Trouble-shooting – sulphur analysis
It is often helpful to determine the type of poisons present
in a feedstock to assist in designing the optimum purification
system. Johnson Matthey Catalysts can offer users of its
products a detailed sulphur analysis services through our
state of the art equipment for the characterisation of
sulphur compounds. The equipment utilizes a
chromatograph with a chemiluminescence detector that
allows for measurement and speciation of sulphur
containing compounds at levels of between 10 and 20 ppbv.
In comparison, the sulphur slip from zinc oxide is typically
50 ppbv and from ultra-purification is 10 ppbv.
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This figure illustrates typical locations for installation of the
catalyst probe. A probe installed upstream of the purification
system will pick up and allow identification of the poisons in
the feed gas. A probe installed downstream of the purification
system will allow pick up and identification of any poisons
that have slipped through the purification system.
Carbon prediction in feed pre-heat coil
One problem that some operators have faced in the past has
been a gradual build up in the pressure drop across the
hydrodesulphurization bed which is greater than expected.
On inspection of the inlet distributor and catalyst bed,
significant amounts of carbon has been found to be have
been deposited. The root cause of this is that although the
bulk gas temperature leaving the feed pre-heat coils is not
high enough to cause hydrocarbon cracking, the internal
metal skin temperature of the coil can be much hotter than
this. In some cases, this temperature is sufficiently high that
hydrocarbons, particularly longer chained species, will crack
and the carbon is deposited on the catalyst bed.
Johnson Matthey Catalysts can provide detailed modelling of
the feed pre-heat coil to determine whether this will be an
issue or not. Using the HYSYS flowsheet package available
from our partner, Aspen Technology, a model can be
constructed that defines the heat and mass balances
around the pre-heat coil. From this heat and mass balance,
a more detailed model of the coil itself is produced using
Aspen Technology’s FIHR program. This allows for
determination of the internal skin temperature of the coil.
Using Johnson Matthey’s in-house carbon cracking models,
it is possible to determine the cracking temperature of the
feed and therefore whether there is a potential problem in
the feed pre-heat coil.
Such modelling is useful in troubleshooting pressure drop
problems over a hydrodesulphurization vessel and also in
determining whether changes in operating conditions will
change the temperature regime such that hydrocarbon
cracking will be an issue.
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KATALCOJM and PURASPECJM purification catalysts are
suitable for the full range of feeds to synthesis gas plants,
whether an off gas, a natural gas, LPG or naphtha. Typical
recommendations for our standard purification products are
given below, however, Johnson Matthey Catalysts will provide
specific recommendations to suit particular plant conditions
depending on the feedstock composition, poisons present
and vessel configuration.
Johnson Matthey Catalysts are experts in difficult and
unusual purification requirements and for these applications
offer the PURASPECJM product range for a wide range of
trace impurity removal. These include HDS catalyst and ZnO
absorbents for low temperature applications, as well as
products to remove the less usual poisons such as mercury
and arsenic compounds.
Catalyst selectorPre-sulphided HDS catalysts may be recommended in the
following circumstances:
Pre-sulphiding can be achieved in situ by injection of a
sulphiding agent with hydrogen at defined conditions.
Alternatively, Johnson Matthey Catalysts can deliver the
catalyst in the pre-sulphided form.
PURASPECJM products may be recommended for removal of
the less usual poisons. The most frequently offered products
are summarised.
Feedstock impurity/ KATALCOJM product
operating situation recommendation
organic sulphur 41-6T
olefins saturation 61-1T
high COx content 61-1T
halide removal 59-3
low sulphur content (single bed) 32-4
moderate sulphur content (single bed) 32-5 & 32-4
high sulphur content (lead lag beds) 32-5
downstream pre-reformer PURASPECJM 2084
long reformer catalyst cycle times PURASPECJM 2084
Operating situation PURASPECJM product
recommendation
mercury PURASPECJM 1156/
PURASPECJM 6156
arsenic PURASPECJM 1152/
PURASPECJM 5152
low temperature HDS KATALCOJM 61-2T
low temperature ZnO PURASPECJM 2020
very high sulphur feeds fully active immediately
high olefin feeds fully active immediately
high carbon oxide feeds avoid methanation
very low sulphur feeds avoid possible over reduction
very high hydrogen feeds avoid possible over reduction
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Catalyst characteristics
Physical properties (typical)
Composition
KATALCOJM 41-6T cobalt oxide/molybdenum oxide/alumina
KATALCOJM 61-1T nickel oxide/molybdenum oxide/alumina
KATALCOJM 59-3 sodium aluminate/alumina
KATALCOJM 32-4 zinc oxide
KATALCOJM 32-5 zinc oxide
PURASPECJM 2084 copper/zinc oxide/alumina
Catalyst KATALCOJM 41-6T KATALCOJM 61-1T KATALCOJM 59-3 KATALCOJM 32-4 KATALCOJM 32-5 PURASPECJM 2084
Form trilobe extrusions trilobe extrusions spherical granules spherical granules spherical granules spherical granules
Diameter 2.5 2.5 2.0-4.75 2.8-4.75 2.8-4.75 2.5-4.75
(mm)
Typical loaded density
(kg/m3) 590 560 860 1140 1350 870
(lb/ft3) 37 35 54 71 84 54
KATALCOJM 61-1T
KATALCOJM 59-3
KATALCOJM 41-6T
KATALCOJM 32-4
KATALCOJM 32-5
PURASPEC 2084
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Belasis Avenue
Billingham
Cleveland
TS23 1LB
UK
Tel +44 (0)1642 553601
Fax +44 (0)1642 522542
Oakbrook Terrace
Two Transam Plaza Drive
Chicago
Illinois 60181
USA
Tel +1 630 268 6300
Fax +1 630 268 9797
For further information on Johnson Matthey Catalysts, contact your local sales office or visit our website at www.jmcatalysts.com
KATALCO, PURASPEC, STREAMLINE and TRACERCO are trademarks of the Johnson Matthey group of companies.
www.jmcatalysts.com© 2005 Johnson Matthey Group
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