Finding Gems in the Rough

Soni O. Oyekan Reforming & Isom Technologist

Marathon Oil AIChE MAC William Grimes Award

November 17, 2008

A Simplified Refinery Flow Diagram

NHT Reformer

Gas Recovery

Sulfur Plant

FCCU

HC

Coker Unit

Gasoline Blending

DHT Distillate Fuels

Atm Unit

Vac Unit

CokeAsphalt

Fuels

Gasoline

Sulfur

LPG, C3=

Crude Oil

LSRN

Naphtha Reforming Basics• Operating Goals

– Produce high octane gasoline blending component from low octane naphtha

– Produce hydrogen – Produce aromatics

• Platinum and Bimetallic Catalysts – Pt/Al2O3/Cl, Pt/Re/Al2O3/Cl, Pt/Sn/Al2O3/Cl – Dual functional (hydrogenation/dehydro, acid)

• Hydrotreated Naphtha Feed – paraffins, naphthenes and aromatics – carbon range of C6 to C11

• Typical Process Conditions – 100 to 300 psig, 900 to 1000 F, LHSV 1.0 to 4.0, H2/HC molar ratio

of 3 to 8 • Hundreds of Reactions:

– dehydrogenation, isomerization, dehydrocyclization, hydrocracking, hydogenolysis, dehydroalkylation

1977 Assignment & Plan

• First assignment in Exxon was to determine the mode of promotion of Re in Pt/Re catalysis

• Immersed myself as much in understanding fundamental Pt, Pt/Re catalysis and the naphtha reforming process

• Worked on cleaning a Hydrotreating catalyst sulfiding unit for “clean sulfur” platinum/rhenium naphtha reforming studies

• Cleaning with Isopropyl alcohol took about 10 weeks! • Developed a working network with fundamental

researchers and surface characterization specialists, sought out mentors and worked diligently

• Was highly driven, challenged and wanted to succeed

Experimental Program• Varied rhenium content on a constant Pt catalyst and used Pt and Re

only catalysts – 0.3 % Pt, 0.3 % Re, 0.3 %Pt/0.3 %Re, O.3 % Pt/0.6 % Re

• Activated the catalysts in a dedicated unit and characterized catalysts for coke, chloride and sulfur

• Conducted test runs in the a common heater using four separate reactor and product separation systems

• Used same operating conditions and same naphtha feed – 950 F, 175 psig, H2/HC molar ratio of 5

• Completed data work up and compared product yields of C5+, H2 and light gases (C1 – C4)

• Characterized spent catalysts for coke, chloride and sulfur • Conducted necessary catalyst surface characterizations • Conducted model compound reforming studies with Heptane and

methyl cyclopentane.

A Sample Set of Test Data

Catalyst (wt. %)

Low Rhenium 0.3 Pt/0.3 Re (A)

High Rhenium 0.3 Pt/0.6 Re (B)

Activity, No 72.0 96.0

C5+ yield, vol. %) 72.0 69.3

• Data indicated 2.7 vol. % lower C5+ yield for B • Lower H2 yield • Higher C1 to C4 gas • Lower coke make • Different C/H ratios for catalyst coke • Sulfur was retained in proportion to Re content • Overall negative catalyst performance data for B • However, data and other factors provided valuable information for developing a mechanism for rhenium promotion effects

Combo Catalyst DataCatalyst Low Rhenium

0.3 Pt/0.3 Re (A)Combo A Catalyst / B Catalyst

Activity 77.0 92.0

H2 yield, wt. % 2.26 2.31

C1 – C4, wt. % 18.82 17.86

C5+ yield, vol. % 74.3 75.5

• Achieved greater than 1 vol % C5+ yield • About $3+ MM dollars a year for a 40 MBPD Platformer • Introduced new combination Pt/Re catalyst systems • Equi-molar, balanced, skewed, high rhenium terms introduced • Determined that rhenium promoted platinum catalysis via minimization of steric hindrance for intermediate compounds • Combination Pt/Re catalyst systems now used worldwide • Studies led to 1 US and 9 patents from other countries

Continuous Catalyst Reforming Process A Major Technology Advancement

• Key objective was getting longer cycle • Note performances of Pt/Sn and Pt were poor • Numerous oil and technology R&D centers discarded poor data

Platinum Catalysis in Naphtha Reforming

72.00

76.00

80.00

84.00

88.00

92.00

96.00

2/18/2

004

2/19/2

004

2/20/2

004

2/21/2

004

2/22/2

004

2/23/2

004

2/24/2

004

2/25/2

004

2/26/2

004

2/27/2

004

2/28/2

004

2/29/2

004

3/1/20

04

3/2/20

04

3/3/20

04

3/4/20

04

3/5/20

04

3/6/20

04

3/7/20

04

3/8/20

04

Time

C5+

, Vol

. %

Pt/Re

Pt

Pt/Sn

UOP & IFP Found Gems In Effective Utilization of Pt/Sn Catalysts

• UOP decided to capture the high C5+ yield edge of Pt/Sn over Pt and Pt/Re catalyst systems

• UOP introduced Platforming with continuous catalyst regeneration system – CCR Platforming in 1971

• Continuous catalyst regeneration systems required – Spherical catalysts for facile circulation – A regenerator for coke burn and catalyst activation

• IFP later introduced its version of continuous catalyst regeneration reforming system

• UOP has about 225 units in commercial operations and Axens (IFP) has 60 units.

• Principal catalytic reforming technology in use for petroleum refining

CCRTM Platforming Unit at Marathon Detroit.

Summary• Soni Oyekan and George Swan of Exxon used “negative” Pt/Re

test data to advantage in fixed bed reforming • I acknowledge the work of George Swan, Bill Baird, Harry

Drushel, Chuck Mauldin, Ken Riley and many others for the Exxon work

• UOP used what many oil and technology companies considered “negative” Pt/Sn data to advantage to develop a major CCR reforming technology process

• Axens and UOP have capitalized on licensing CCR technologies to generate hundreds of millions of dollars for their companies.

• In your research studies, critically analyze and look for gems in “negative” data !

Thank you for your patience and time