Advanced Catalyst Technology and Applications for 

Higher Quality Fuels and Lubes 

J. S. Beck, T. F. Degnan, M. C. Kerby, and D. O. Marler 

ExxonMobil Process Research Laboratories 

1545 Route 22 East 

Annandale, New Jersey 08801 

Introduction 

Catalysts are among our most powerful tools for creating value 

while meeting the challenges of the petroleum and petrochemical 

industries [1]. ExxonMobil has continued its long standing tradition 

of applying industry-leading catalyst technology to enable the 

conversion of complex molecules in crude oil selectively and 

efficiently into valuable products needed in fuels, lubricants, and 

chemicals. The merger of Exxon and Mobil brought together a 

unique synergy of metal oxide and zeolite catalysis expertise and 

ExxonMobil continues to be an industry pacesetter in the broad 

application of catalyst technology. 

An overview of our active materials platforms will be reviewed. 

Emphasis will be given to how zeolitic, mesoporous, and metal oxide 

catalysts are discovered, developed, and commercially implemented 

to manufacture higher quality fuels and lubricants within 

ExxonMobil. Only through a fundamental understanding of how 

catalysts behave at the molecular level, can innovations in new 

catalyst platforms continue. 

In order to accelerate the pace of catalyst innovation, 

ExxonMobil is exploiting the use of high throughput experimentation 

(HTE) to more rapidly discover and implement new catalyst 

technologies that are critical for future advances. To this end, 

ExxonMobil Research and Engineering Company and Symyx 

Technologies, Inc. have entered into a multi-year technology alliance 

focused on using HTE to enhance downstream and chemicals R&D 

activities. 

ExxonMobil Catalyst Platforms and Applications 

Other than a few purely thermal processes, catalysts are used in 

almost all refining and chemical processes. Catalysts accelerate 

reactions and lower energy requirements while also improving value 

by selectively making the desired products. We continue to design a 

broad array of catalyst platforms ranging from shape selective 

zeolites to produce world class lubricants, to high activity metal 

oxide catalysts to manufacture low sulfur transportation fuels. 

ExxonMobil’s capability spans across the entire catalyst 

pipeline from the discovery of new catalysts to commercial 

implementation. A strong fundamental science base drives the 

discovery of new catalyst systems. Through our internal knowledge 

of desired hydrocarbon transformations, we can match the molecule 

size and conversion needs to catalyst design. In the development 

phase, the most viable catalyst is selected and a process initiated to 

find a cost effective preparation route for the catalyst of choice. We

then set a path to scale-up the catalyst, which could include internal 

manufacture or joint work with a catalyst vendor. Finally, we 

commercialize the catalyst with the objective to apply it as broadly as

possible across our refinery circuit. This feedback loop provides 

critical performance information about the performance of the 

catalyst and allows us to further identify and develop next generation 

catalyst systems. 

 

Zeolite Catalysts. Zeolites are an important class of molecular 

sieves and are used to collect, separate, and transform a wide range 

of organic molecules [2]. They are crystalline aluminosilicate 

frameworks composed of tetrahedral silica and aluminum atoms

linked by oxygen atoms, which can be synthesized into a variety of 

pore sizes and shapes. Zeolite discovery is a complex science. 

Components such as silica, alumina, and an organic templating agent, 

which provides the shape of the material, are combined in a 

controlled pH and temperature environment to form the crystalline 

product. The organic template is then removed through calcination. 

This leaves behind the crystalline zeolite framework with a pore size 

that matches the organic template. A significant number of 

experiments (100’s-1000’s) are required to ‘map’ the synthesis space. 

Zeolites can be uni-dimensional or multi-dimensional and exist in a 

wide assortment of molecular sizes, shapes, and intersecting channels

(Figure 1). Unique combinations of pore size, shape, and 

dimensionality can provide a wealth of new zeolites. ExxonMobil 

has synthesized well over 50 unique zeolite structures. 

ZSM-23 (MTT)

1-Dimensional

10R 4.5 x 5.2 (Å)

ZSM-35 (FER)

2-Dimensional

10R 4.2 x 5.4 (Å) 

8R 3.5 x 4.8 (Å)

Intersecting 10R-8R

MCM-68

3-Dimensional

12R 6.5 x 6.8 (Å) 

10R 5.1 x 5.5 (Å)

Intersecting 12R- (2)10R

Figure 1. Zeolites can be formed in a variety of molecular sizes and 

shapes. 

With this array of zeolitic materials, it is possible to tailor the 

catalyst to perform the desired reactions at high rates and selectivity. 

The ability to match the size of the molecule to the size of the zeolite 

or molecular sieve is called “shape selectivity” in which ExxonMobil 

is a leader (Figure 2). 

Zeolite Y

ZSM-5

Pore Size Å

40

60

80

100

5

10

20

Gasoline Gasoil Resids

100Å

100Å

Pore Size (20-100+Å)

Adsorption, Separation

Catalytic Conversion of

Large Molecules

ZSM-5

MCM-41

MCM-41

Figure 2. Use of shape selectivity to design catalyst pores for 

selective conversion of molecular types. 

Today, the shape selectivity concept is the basis for ~20 

commercial processes with annual hydrocarbon throughput in excess 

of 70 million metric tons per year. For example, catalytic cracking, a 

key refinery process used to produce gasoline and diesel utilizes 

zeolite-Y, which selectively cracks heavier vacuum gas oil 

molecules. ZSM-5, a smaller pore zeolite, can be added as a cocatalyst to the cat-cracker to promote the selective formation of 

propylene, a valuable chemical product. Another opportunity for 

exploiting shape selectivity concepts lies in the modification of 

mesoporous molecular sieves for reaction or separation of larger 

molecules. Researchers have functionalized the pores of MCM-41 to 

selectively adsorb low concentrations of metals such as Hg and Ag 

while excluding other metals [3, 4]. 

The zeolitic crystal is formulated into a finished catalyst through 

the addition of various components such as binders (e.g. silica, 

alumina, zirconia, titania), modifiers, metals and metal oxides (e.g. 

Prepr. Pap.-Am. Chem. Soc., Div. Fuel Chem. 2004, 49(2), 507
Pt, Pd, Ni, Co, Mo). These components can be added to optimize the 

finished catalyst’s acidity, metals activity, porosity, and physical 

integrity. 

One key application of shape selectivity is ExxonMobil’s 

selective catalysts dewaxing technology. Dewaxing rearranges the 

structure of primarily straight chain molecules to ensure they have 

the correct flow properties at the desired temperatures. The MSDW2 catalyst technology is a medium pore zeolite which applies shape 

selectivity, proper control of acidity, and a metal driven 

hydrogenation-dehydrogenation function to selectively convert or 

‘dewax’ the straight chain molecules to a slightly branched 

molecules as it enters the zeolite pore. More bulky or branched 

molecules, which already have beneficial lubricant properties, are 

excluded from entering the zeolite pore. Thus, this catalyst 

technology only works on the molecules that need to be converted. 

Metal Oxide Catalysts. Another important class of catalytic 

materials that are widely used in the refining industry are metal 

oxides. These materials, which are typically mixtures of CoMo or 

NiMo oxides on silica-alumina supports, are primarily used in key

refinery processes called hydroprocessing. This technology uses the 

catalytic addition of hydrogen to selectively remove sulfur and 

nitrogen from various refinery streams to produce low sulfur gasoline 

and diesel. More hydrogen intensive hydroprocessing applications 

can also reduce other components such as olefins and aromatics. 

The prime contributor to sulfur in the gasoline pool is from the 

cat-cracking unit. While it is possible to hydrotreat the sulfur to very

low levels, cat naphtha also contains a considerable amount of 

valuable olefins, which are high in octane. Thus, the challenge is to 

selectively remove sulfur while minimizing the saturation of olefins. 

This is particularly an issue for higher sulfur cat naphthas. 

ExxonMobil’s SCANfining technology [5] utilizes a proprietary

CoMo catalyst, jointly developed with Akzo Nobel, to selectively

reduce the cat naphtha sulfur while minimizing the saturation of high 

octane olefins (Figure 3). 

Figure 3. ExxonMobil’s SCANfining technology selectively

removes sulfur while minimizing octane loss.

The CoMo system is characterized by high metals dispersion 

with special attention given to the support-metal interactions. 

SCANfining II, is even more selective particularly for higher sulfur 

cat naphthas. SCANfining has been rapidly commercialized and will 

be used in 30 units worldwide to manufacture low sulfur gasoline. 

A new generation of ultra-high activity catalysts for nitrogen 

and sulfur removal was recently discovered by ExxonMobil and 

jointly developed with Akzo Nobel. This catalyst system called 

NEBULATM is unique in that it is a bulk mixed metal oxide, which 

maximizes the number of active sites per volume of catalyst [6].

NEBULATM has shown very high hydrodesulfurization and 

hydrodenitrogenation activities compared to conventional catalysts 

(Figure 4). This performance advantage enables the refiner to 

produce ultra low sulfur diesel in existing units. NEBULATM has 

been commercialized in a number of distillate hydrotreating and 

hydrocracking applications. 

0

100

200

300

400

500

600

700

800

900

1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

Year

HDS Activity

N e bula

C o M o Alu m in a

Figure 4. NEBULATM catalyst technology represents a step change 

in Hydroprocessing catalysts. 

Future Advances in Catalysis

Catalysis will continue to play a crucial role in the petroleum

and petrochemical industries. Fuel and lube compositions are 

expected to evolve in response to environmental legislation and 

advanced engine design. In addition, petroleum feedstocks will 

become heavier and sourer with time. This will require future 

catalysts, which are higher in activity and selectivity, more poison 

tolerant and stable for longer periods. 

ExxonMobil is committed to accelerate the pace of innovation 

and delivery through the use of HTE. ExxonMobil and Symyx 

Technologies, a leader in the development and application of highspeed materials research methods, have formed a technology alliance 

focused on the application of HTE technology across ExxonMobil's 

downstream and chemical portfolio. Implementation of HTE 

methods will enhance ExxonMobil’s core competency in catalyst 

research and development. This alliance includes high throughput 

catalyst synthesis, characterization, and evaluation tools coupled with 

an informatics platform to more rapidly discover and implement 

future catalyst systems. 

References

(1) Kaufmann, T. G.; Kaldor, A.; Stuntz, G. F.; Kerby, M. C.; Ansell, L. L. 

Catalysis Today., 2000, 62, 77. 

(2) Chen, N. Y.; Garwood, W. E.; Dwyer, F. G. Shape Selective Catalysis in 

Industrial Applications, 2nd ed., Marcel Dekker, New York, 1996.

(3) Beck, J. S.; Vartuli, J. C.; Roth, W. J.; Leonowicz, M. E.; Kresge, C. T.; 

Schmitt, K. D.; Chu, C. T-W. Olson, D. H.; Sheppard, E. W.; McCullen, 

J. B.; Higgins, J. B.; Schlenker, J. L. J. Am. Chem. Soc. 1992, 114, 

10834. 

0

1

2

3

4

5

6

0 3 0 6 0 9 0

P r oduc t S u l f u r , w ppm

Octane Loss, R+M/2

H i gh S Fe e d S C A N f i n i ng I

Low S Fe e d S C A N f i n i ng I

H i g h S Fe e d

S C A N f i n i ng I I

(4) Feng, X., Frywell, G.E., Wang, L.Q., Kim, A.Y., Liu, J., Kemner, K.M., 

Science, 1997, 276, 923 

(5) Riley, K. L.; Kaufman, J. L.; Zaczepinski, S.; Desai, P. H.; Mayo, S. W. 

Akzo Nobel Catalyst Symposium, Vol. G-3, 1998, 1.

(6) Meijburg G.,Brevoord E., Plantenga F., Mayo S., Inoue Y., Fujita K., 

Lewis W., Sapre A., NEBULATM for Hydrocracker Pretreat Operations, 

ERTC 2003, London.

Prepr. Pap.-Am. Chem. Soc., Div. Fuel Chem. 2004, 49(2), 508