The addition of fresh catalyst to theFCC unit is maintained continuous-ly for two reasons: first to maintain

optimum catalytic performance, and sec-ond to maintain the appropriate physicalproperties and quantity of the circulatinginventory. This article highlights the keycatalyst properties that should be moni-tored and can be used for troubleshootingof FCC operating problems caused bychanges in catalyst physical properties orcatalytic performance. The article also pro-vides new FCC process engineers andoperating personnel with an understand-ing of the impact of catalyst properties onFCC unit performance.

Maintaining the appropriate catalyticactivity and selectivity factors is largelydetermined by the addition rate of freshcatalyst and withdrawal rate of equilibri-um catalyst. The following factors willestablish the proper catalyst managementprograms:––––Yield and product quality objectives––––Contaminant metals levels to be toler-ated––––Optimum equilibrium catalyst activitylevel as determined by feed quality andcracking severity––––Response of unit conversion to fresh cat-alyst additions––––Response of unit conversion to equilib-rium catalyst activity level

The optimum equilibrium catalystactivity level must be established for anyspecific unit operation. In order to opti-mise the performance of the FCC unit, theproperties of the FCC catalyst such asactivity and physical structure must bemonitored on an ongoing basis.

Microactivity testing (MAT) is a labora-tory procedure which measures the degreeto which a catalyst sample can crack or“convert” an FCC feedstock sample. Thisprocedure is used to determine the crack-ing activity of the catalyst independent ofthe specific unit operating conditions andfeedstock. Equilibrium FCC catalyst sam-ples are collected from commercial FCC

operations and subjected to microactivitytesting after calcination to remove residu-al carbon.

MAT results are reported on a compre-hensive equilibrium catalyst reportingsheet. This information sheet, along withchemical composition and physical prop-erties, often called an ECat sheet, is a criti-cal tool in the optimisation of a fluid cat-alytic cracking unit.

It is important to note that there can bewide variation in the equilibrium activitynumbers. Therefore, in addition to look-ing at individual data points, it is recom-mended that catalyst activity be moni-tored on the basis of a three- to four-weekmoving average to observe trends. Thesame microactivity procedure can be usedto monitor the cracking activity of thefresh FCC catalyst delivered to the refinery.

Equilibrium catalyst activity is a func-tion of many independent and dependentparameters in both the catalyst manufac-turing process and commercial crackingoperation.

First and foremost, catalyst activity is afunction of the properties of the fresh cat-alyst delivered from the manufacturer.FCC catalyst provides cracking activity viatwo mechanisms – zeolitic cracking andmatrix cracking.

Zeolitic cracking is a function of manyfactors, including zeolite type, zeolite levelin the formulation and the type of treat-ment (rare earth or alternative) providedto stabilise the zeolite. Matrix cracking is afunction of the amount of active aluminacomponent present in the matrix, thematrix surface area, and accessibility oflarge molecules provided by the porestructure.

The relative amounts of zeolitic andmatrix activity can be determined andmonitored via surface area measurements.Total surface area in an FCC catalystincreases with both increasing zeolite con-tent and matrix activity. Total catalystsurface area is routinely reported on theequilibrium catalyst data sheet. In order to

separate the individual contributions ofzeolite and matrix structures to catalystsurface area, it is necessary to employ amore rigorous surface analysis technique.Refiners should verify that either thematrix surface area or the zeolite-to-matrix(Z/M) ratio is reported on a routine basis.Either of these figures will provide theinformation required to calculate both thezeolite and matrix contributions to cata-lyst surface area.

Matrix surface area is often used as anindicator of matrix activity. While highfresh catalyst matrix surface area (125 to175m2/gram) generally indicates the pres-ence of active matrix, it can be deceivingto use this value as the only measure of rel-ative matrix activity. FCC catalyst matrixcontains many components, includingbinders, clay, fillers, active matrix materi-als and additives such as metals traps, andSOx reduction agents. All of these materi-als contribute to matrix surface area, butonly one component – crystalline eta orgamma alumina – contributes to “matrixactivity”, as it is most often discussed.

However, since many catalyst compo-nents contain alumina, including zeolite,obtaining reliable values for eta andgamma alumina content is not possible. Impact of FCCU operation on catalystactivitySecond, equilibrium FCC catalyst activityis a function of the daily replacement (andwithdrawal) rate of catalyst and the cata-lyst deactivation rate. Key FCCU factorswhich affect catalyst deactivation rate arelisted below. These factors are interrelatedand essentially encompass the combinedeffects of temperature, time, metals con-tamination and the presence of steam.

1.Vanadium in FCC feedstock depositsitself on the surface of cracking catalystand migrates to zeolite, where it destroysthe crystalline structure. This results in apermanent loss of a portion of the zeolitecracking activity.

2.Regenerator temperature influencesthe rate of zeolite activity loss via both

Troubleshooting FCCU operating problems

Important FCC catalyst properties and the way they affect unit performanceare described in this article, which also reviews operating problems that can

be corrected, based on analysis and adjustment of the catalysts’ properties

Jack R Wilcox Dennis C Kowalczyk Robert J Campagna

Refining Process Services Inc

RREEFFIINNIINNGG

PPTTQQ WWIINNTTEERR 11999966//9977

2277

hydrothermal and vanadium-induceddeactivation mechanisms. Matrix activitywill also deactivate in the FCC regeneratorover time as a function of temperature.

33..The level of excess oxygen in the FCCregenerator can greatly influence thedegree to which vanadium on the catalystsurface is oxidised. Refiners who convertto oxygen enrichment of regenerator airoften report activity loss ranging as high as4 to 5 MAT numbers.

44..The presence of contaminant metalsother than vanadium can also add to thetotal deactivation profile in a commercialFCC unit. The presence of sodium at thezeolite site interacts with vanadium togreatly exacerbate the destructive tenden-cy of both of these metal contaminants.Certain contaminant metals can alsointeract with the active matrix sites in thecatalyst and render them inaccessible.

55..The presence of steam in the catalystparticles will greatly enhance zeolite deac-tivation resulting from dealumination.FCC regenerator steam is present from anumber of sources, including humidity inthe regenerator air, entrained steam fromthe catalyst stripping section, and waterformed via combustion of coke. Steam isalso produced during combustion ofunstripped hydrocarbon, and for catalystparticles containing significant amountsof unstripped oil, steam concentration inthe pores can reach 25 to 35 mole%.Troubleshooting problems with catalystactivityFrom time to time, most FCC operationsexperience bouts of declining levels offeedstock conversion. This can often beattributed to factors related to deteriora-tion in feedstock quality, such as increas-ing carbon residue and asphaltene con-tent, decreasing API gravity, increasingaromatic content and increasing basicnitrogen content. However, there areother instances when unit conversion lossis related to a loss of fundamental catalyt-ic cracking activity.

A gradual decline in equilibrium cata-lyst activity may be difficult to diagnose inan FCC unit, given all the noise inherentin commercial operation. That is why it isimportant to develop a meaningful mov-ing average trendline for catalyst activitybased on the catalyst activity numbersreported by each supplier. Although theremay be differences in the absolute valuesreported by each laboratory, the movingaverage trendlines should be similar.Troubleshooting catalytic activity lossIf it is determined that catalyst activity asmeasured by MAT testing is declining,there are a number of potential root caus-es to be investigated:

Increased catalyst deactivation date.Increased catalyst deactivation is evi-denced by declining MAT activity with nocorresponding decrease in catalyst addi-

tion rate or increase in catalyst vanadiumand/or sodium level.

It is important to observe if the equilib-rium catalyst activity loss is accompaniedby more fines (0 to 40 micron particles)production. Further, FCC operators mayobserve an increase in catalyst losses fromthe unit. The combination of these twoconditions may indicate a new source ofboth deactivation and attrition.

A new source of steam or some alter-ation in an existing source of unit steamcould create conditions conducive to bothcatalyst breakage and zeolite deactivation.FCC unit operators should undertake athorough inspection of all potential trou-blespots and look for signs of increasedsteam usage, steam jets such as wouldresult from an open blast steam nozzle,and the presence of wet steam.

In the FCCU, matrix activity loss resultsprimarily from thermal mechanisms whilezeolite deactivation results primarily fromhydrothermal mechanisms. Therefore,increased catalyst deactivation caused bysteam would typically result in decreasingzeolite surface with no correspondingchange in matrix surface area.

Increased thermal deactivation. If equilib-rium catalyst activity loss is accompaniedby both decreasing matrix and zeolite sur-face area, it would be reasonable to suspectsome form of increased thermal exposureprofile on the catalyst. Unit operatorswould first look for signs indicating somechange in the regenerator operation.Potential changes which could lead to thistype of situation are as follows: ––––Disruption of the regenerator air gridcould lead to pockets of excessive oxygenconcentration and localised hot spots inthe catalyst bed––––Increases in air rate to the regeneratorcould lead to increased circulationthrough the cyclones, combined with anafterburn condition which creates hottercatalyst than would be indicated by thedense bed temperature––––Disruptions in the catalyst stripper oper-ation could result in increased oil carry-over, resulting in catalyst internal temper-atures 150°C to 200°C higher than thebulk bed, with little observed difference inregenerator dense bed temperature.Diagnosis would involve study of thestripper operating conditions and collec-tion of a stripper catalyst sample for deter-mination of free oil content. A modifiedversion of FCC Reaction Mix Samplingcan be used to observe potential problemsin catalyst stripper operation.

Increased vanadium damage. Decreases inFCC catalyst equilibrium activity are oftenaccompanied by increases in vanadiumlevel on the catalyst. In the FCC regenera-tor, vanadium oxidises to the pentoxideform. Some FCC regenerators operateabove the melting point of vanadium pen-

toxide, which allows vanadium to meltand flow into the particle and reach thezeolite crystals. It has also been observedthat vanadium pentoxide in the presenceof steam will form a vapour-phase specieswhich can migrate to other catalyst par-ticles.

If increasing catalyst vanadium contentis causing reduced MAT activity, refinershave several options for recovering theresultant loss in catalyst activity. They canincrease the addition rate of fresh FCC cat-alyst. A second alternative would involvemodification of the current catalyst for-mulation to incorporate more vanadiumtolerance capabilities into the catalyst.However, changing catalyst formulationmay result in a shift in the product selec-tivity profile.

There are several new tools for reducingthe impact of vanadium on FCC catalystactivity which include separate particletraps and liquid phase vanadium passiva-tion compounds.

Increase in other metals contaminants.Many refiners have experienced signifi-cant increases in catalyst deactivation rateas a result of increased sodium depositionon catalyst. Increased sodium concentra-tion typically results from upsets at thecrude oil desalter or from addition of pur-chased feedstocks. Purchased feedstocksare often contaminated with salt water.

It is important to note that sodium ispresent in the catalyst as a result of themanufacturing process. The level of sodi-um on fresh catalyst must be consideredwhen determining changes in sodiumconcentration. It is well known that sodi-um interacts with vanadium on the FCCcatalyst to exacerbate the rate of catalystdeactivation. FCC feedstocks also maycontain other contaminant metals whichcan interact to block or destroy matrix andzeolite active sites.

Inconsistency in catalyst addition qualityand amount. Refiners should take steps toensure that the quality and addition rateof fresh FCC catalyst remains constant. Itis important to verify that the MAT activi-ty and surface area, along with physicalproperties such as particle size distributionand catalyst attrition properties, are moni-tored frequently and are relatively similarfor each delivery.Impact of FCC catalyst physical proper-ties on FCC unit operationThe second criterion governing catalystmanagement is the quantity and physicalcondition of the circulating inventory. Thecatalyst physical properties have a directimpact on fluidisation characteristics andcollection system (cyclone) efficiency.Important FCC catalyst physical proper-ties are described below.Density and particle size distribution The apparent bulk density (ABD) of freshFCC catalysts is typically between 0.62

PPTTQQ WWIINNTTEERR 11999966//9977

2288

RREEFFIINNIINNGG

and 1.0g/cc (40–62lb/ft3). The fresh densi-ty is a function of the raw materials andthe manufacturing procedures. Bulk densi-ty will vary inversely with pore volume.Equilibrium catalyst will usually show abulk density that is about 0.1g/cc higherthan the fresh catalyst, due to the loss ofsome pore volume as normal deactivationoccurs.

For most units, ABD is not a significantconcern. Its effects on catalyst losses andcirculation properties are usually smalland undetectable. In some cases, however,a significant change in catalyst density cancause important changes in the operationof the unit.

First, a catalyst density change willchange the correlation of bed height withdelta P. This means that if a lower densitycatalyst is added and the same delta P ismaintained, the bed level will increase.This effect could be important if the dis-tance between the cyclone inlet and thebed is close to the transport disengagingheight (TDH), which is the minimum dis-tance that should be maintained betweenthe bed and the primary cyclone inlet. Ifthis distance is not maintained, losses willincrease.

Use of lower density catalysts will alsotend to slightly increase entrainmentrates. This effect is small in comparison tothe effect of particle size on entrainment.Thus, if a lower density catalyst is desiredwithout increased entrainment, a smallincrease in the fresh average particle size isall that should be required. Also, in nor-mal circumstances (with low to moderatesuperficial gas velocities in the reactor andregenerator) any changes in losses due todifferences in catalyst densities will benegligible.

The effects of catalyst density on cata-lyst circulation are more complicated. Onone hand, lower density catalysts cannotgenerate as much potential delta P per foot

of standpipe and thus one might concludethat the maximum catalyst circulationcapability of the unit might be reduced bydensity. On the other hand, lower densitycatalysts are easier to fluidise and usuallydeliver a higher percentage of their maxi-mum delta P generating capacity.

Here again, for most units, the differ-ences in catalyst circulation capacity forlow and high density catalysts will not besignificant. For units that are sensitive tocirculation upsets due to sudden losses ofslide valve delta P, lower density catalystsmay have a slight advantage.

As with entrainment, the catalyst parti-cle size distribution plays a larger role influidisation than does catalyst density.Relatively small changes in particle sizedistribution can offset most of the effectsof catalyst density on catalyst fluidisation.In general, catalysts with more fines (0 to40 micron particles) are easier to fluidiseand circulate. Of course, adding more finesor decreasing the average particle size of acatalyst will increase entrainment ratesand will tend to increase losses.

The particle size distribution of thefresh catalyst can be varied over a fairlywide range by all of the catalyst suppliers.The user will ordinarily specify the size byordering a “fine”, “regular” or a “coarse”catalyst grade. Typically, a fine grade couldhave an average particle size (APS) as lowas 55 microns with a fines content as highas 20wt%. The regular grades normallyrange in APS from 70 to 75 microns with afines content of about 10 wt%, whilecoarse grades can have an APS as high as95 microns with as few as 5wt% fines.Attrition indexThere are many different attrition teststhat are run throughout the industry.Most attrition tests measure the amount of0 to 20 micron fines that are producedafter subjecting the catalyst to a highvelocity air jet for a given period of time.

Particle size distribution is measuredbefore and after testing, and the attritionindex is often equal to the increase in theconcentration of particles smaller than 20microns.

Catalysts with attrition indices below5.0 are considered to have a very highlevel of particle integrity. Catalysts withattrition indices between 5.0 and 10.0 areconsidered moderately hard and shouldrun acceptably in most units. In a normaloperation, a catalyst with an attritionindex of 10.0 would be expected to showlosses that are 5 to 10 per cent higher thana catalyst with an attrition index of 1.0.

It should be noted that all of the cata-lyst manufacturers have significantlyimproved their ability to make hard cata-lysts over the past several years. In 1980,typical attrition values, as measured bythis type of test, were 15 to 20. Today,most catalysts are below 10.0.Impact of physical properties on cata-lyst flowMaintaining smooth and uniform catalystcirculation helps ensure optimum perfor-mance of the fluid catalytic cracking unit.Catalyst circulation is maintained by thedifferences in density of the fluidised cata-lyst at various points in the flow system.

Relatively high flowing densities in thecatalyst standpipes essentially generate ahydrostatic head producing the circula-tion. This pressure head must be sufficientto overcome friction losses and pressuredrops across slide/plug valves and distribu-tors. FCC units of every design have, forvarious reasons, experienced catalyst circu-lation difficulties. Usually, the circulationcan be stabilised by adjusting catalystphysical properties or catalyst standpipeoperation.

The usual indication of erratic catalystcirculation is a sudden decrease or fluctua-tion in slide valve differential pressure.These fluctuations often signal more sig-

PPTTQQ WWIINNTTEERR 11999966//9977

3300

RREEFFIINNIINNGG

AA BB CC DD EE FF Normal Maldesigned Damaged Flooded Broken Catalyst

operations cyclones cyclones diplegs plenum attrition

Particle size Regen Precip Regen Precip Regen Precip Regen Precip Regen Precip Regen Precip0.5 – 73.6 – 24.1 – 1.0 – 18.6 – 2.4 – 82.55–10 1.0 14.7 0 3.5 0 0.6 1 6.8 0 0.9 1.0 11.710–20 – 8.3 – 19.4 – 0.5 – 5.2 – 0.9 – 5.420–40 15.0 2.9 6 38.6 1 16.5 10 38.5 10 17.2 17.0 0.440–80 53.0 0.2 55 12.5 35 56.8 58 27.7 50 56.4 54.2 060+ – 0.3 – 1.9 – 32.3 – 9.4 – 26.1 – 080+ 31.0 0 39 0 64 14.6 31 3.2 40 22.2 28.8 0APS 64 – 71.0 – 86.0 – 66.0 – 69.0 – 62.0 –

Unit loss#/bbl 0.04 0.09 0.22 12 0.25 0.25

Comment Dirty stack Puffing Clean stack Dirty stack

Equilibrium catalyst particle size as indicator of regenerator problems

Table 1

nificant upsets which may occur if stepsare not taken to stabilise the situation. Asthe slide valve control becomes erratic,reactor riser temperature and spent cata-lyst stripper level become ragged. This canlead to unstable main fractionator and wetgas compressor operation due to conver-sion changes.

Circulation difficulties usually resultfrom changes in catalyst physical proper-ties, mechanical equipment damage,standpipe blockage, or standpipe aerationproblems.

Catalyst fines, primarily the 0-20micron fraction – either generated by attri-tion or supplied with fresh catalyst – areessentially lost through both the reactorand regenerator collection systems. Inorder to obtain the required particle sizedistribution for any given FCCU configu-ration to maintain uniform calculation,fresh catalyst must be continuously addedto the unit. Proper fluidisation of flowingcatalyst in the transfer lines is essential tostable FCCU operation.

A basic measure of the behaviour of flu-idised FCC catalyst used to determine howchanges in fluidisation media, particle sizedistribution and particle density mayaffect standpipe fluidisation is describedby the equation in the panel below

The ratio of UMb/UMf is larger than oneand, as the ratio increases, better qualityfluidisation properties are exhibited. Therequired level of UMb/UMf is not an abso-lute value, but is specific to unit configu-ration and operation. Meaning-ful unitoperating data, combined with historicaldata for both fresh make-up and circulat-ing equilibrium catalyst, typically providessufficient input to determine if the fluidis-ation problem is due to mechanical or cat-alyst property changes.

The following parameters favoursmooth fluidisation:——Lower catalyst particle density ——Lower mineral density——Increased pore volume——Lower average particle size——Increased fines content (fines = wt% lessthan 45 microns)——Higher density and viscosity offluidising gas.

The quantity of fines in the cir-culating catalyst inventory has adirect impact on the fluidisationand resulting circulation. Thefines level will be established bycyclone design and performance,fresh catalyst fines content andattrition resistance, and by otherfactors, such as gas velocities andcatalyst entrainment rate affect-ing cyclone efficiency.

The less than 20 microns con-tent in the circulating inventoryis typically between 0 and 30 percent, while the amount less than

40 microns is usually between 4 and 10per cent. Fresh catalyst will have typically2 per cent and 14 per cent for the less than20 and 40 microns respectively.Directionally improving the catalyst prop-erties improves the fluidisation character-istics as follows; it:——Reduces minimum fluidisation velocity——Reduces minimum bubbling velocity——Increases the ratio of minimum bub-bling velocity to minimum fluidisationvelocity——Increases time for catalyst deaeration.

The fines level maintained in the circu-

lating inventory is a function of thecyclone performance. Frequent analysis ofthe catalyst physical properties, particular-ly equilibrium catalyst density and particlesize distribution, is required to monitorcyclone performance. Catalyst losses fromthe unit are generally acceptable as long asslurry oil BS&W or flue gas dust emissionlevels are not excessive.

An increase in losses through both reac-tor and regenerator, while the fines indi-cated by fresh catalyst and equilibriumcatalyst PSD remain constant, indicatesthe generation of fines in the unit. A typi-

cal shift in catalyst PSD in this sit-uation is shown in column F inTable 2. The cause is either anintrinsic attrition resistance prob-lem with the catalyst itself orsome source of attrition in theunit. If the equilibrium catalystactivity or surface area is decreas-ing simultaneously it can beassumed that the attrition sourceis causing deactivation due tohigh velocity steam.

An increase in catalyst losseswhile the average particle sizeincreases indicates a cycloneproblem. Factors which will causedeteriorating cyclone performance

PPTTQQ WWIINNTTEERR 11999966//9977

3322

RREEFFIINNIINNGG

Figure 1 Particle size vs cyclone loading: for particle densities 1.2 to 1.6gm/cc

6600 6655 7700 7755 8800 8855 9900AAPPSS MMiiccrroonnss

1.2gm/cc

1.5gm/cc

1.3gm/cc

1.6gm/cc

1.4gm/cc

2255fftt DDiisseennggaaggiinngg hheeiigghhtt33..00fftt SSuuppeerrffiicciiaall vveelloocciittyy

00..77

00..66

00..55

00..44

00..33

00..22

00..11

00

DDeenn

ssttyy

aatt cc

yycclloo

nnee

–– llbb

//fftt33

UMb/UMf =2300pg0.126µ0.523 exp(0.716 F45)

dp0.8 (g[pp – pg])0.934

UMb = Superficial gas velocity at minimum bubbling, M/secUMf = Superficial gas velocity at minimum fluidisation,

M/secpg = Gas density, kg/Mpp = Particle density, kg/Mµ = Gas viscosity, kg/M-secF45 = Fraction of fines less than 45 micronsg = Gravitational constantdp = Mean particle size

Equation: FCC catalyst fluidisation

include: misdesigned cyclones; increased solids loading;increased gas loading; damaged cyclones due to holes incyclone body, gas tube or diplegs; loss of dipleg seal; stuck trick-le/flapper value, and erosion of internal lining.

Though possible, it is not likely that conformance to currentdesign criteria followed by cyclone designers would lead togross design errors. If a design error did occur, a shift in catalystPSD would appear as shown in column B in Table 1.

Increased solids and gas loadings are a result of higher actu-al vessel velocity. The entrainment of catalyst will increase withincreased superficial gas velocity. An increased load can alsoresult from poor air distribution causing localised high veloc-ities. This also causes higher cyclone outlet temperatures dueto afterburning.

Increasing the degenerator dense bed level sometimes helpsalleviate this situation. Once the cyclones are badly eroded,losses become increasingly higher and the unit must be shutdown to repair the damage. Indications of damage to thecyclone will result in an increase in average particle size of thecirculating catalyst as shown in column C in Table 1.

Flooding cyclone diplegs or damaged dipleg outlet valueswill lead to higher losses. A shift in catalyst PSD as well as visu-al inspection of the regenerator stack will indicate dipleg prob-lems as shown in column D.

A high catalyst level in the regenerator dense bed will causea backup of catalyst in the cyclone dipleg and can cause thedipleg to flood. In order to accurately determine the bed level,two separate differential pressure transmitters for measuringthe height and resulting density of the catalyst bed arerequired.

A change in catalyst type may cause a change in catalyst bedlevel, due to a difference in catalyst bulk density. Typically,cyclone secondary diplegs are oversized in the event that theprimary cyclones will, through excessive erosion or other dam-age, lose efficiency, resulting in increased carryover of catalystto the secondary cyclone. However, this is generally not a largeproblem as the increase in fines level and lower average particlesize to the secondary cyclone normally improves fluidisation inthe secondary cyclone dipleg.

The impact of particle size and particle density on catalystentrainment to the cyclone is shown in Figure 1. Cyclone oper-ation will change with these catalyst physical properties.Operating the unit while utilising a high particle density cata-lyst has the following effect: high particle density catalystreduces entrainment of catalyst to the cyclone inlet, resultingin lower solids loading to the first stage cyclone and subse-quently to the second stage cyclone.

Reduced solids loading to the second stage cyclones increas-es catalyst residence time in the diplegs and increases the pos-sibility of de-aerating the catalyst before it leaves the dipleg.The longer the dipleg and the greater the submergence of thedipleg into the dense bed will result in increased gas compres-sion and catalyst residence time. Both of these factors willdirectionally increase defluidisation of catalyst in the diplegand produce “stick-slip” flow.

Jack Wilcox is vice president, catalytic cracking technology, withRefining Process Services Inc, Cheswick, Pennsylvania, USA. He providesFCC optimisation, troubleshooting and technology evaluation services torefiners around the world.Dennis Kowalczyk is vice president, operations. He coordinates FCCreaction mix sampling test runs and is responsible for MagnaCat andMVP vanadium passivation commercialisation licensing activities.Robert Campagna is president of Refining Process Services Inc. Heserves as director of technical services and is involved in FCC catalystevaluation and optimisation studies and refinery technical services, andalso provides FCC technical training.

PPTTQQ WWIINNTTEERR 11999966//9977

3333

RREEFFIINNIINNGG