ajit sapre - exxonmobil
TRANSCRIPT
Technology solutions for upgradinglube base oil production
Ajit SapreLicensing Director, Europe, Middle East & AfricaEXXONMOBIL RESEARCH & ENGINEERING
Technology solutions for upgradinglube base oil production
Ajit SapreLicensing Director, Europe, Middle East & AfricaEXXONMOBIL RESEARCH & ENGINEERING
Technology Solutions forUpgrading Lube Base Oil Production
Ajit V. SapreTim H. HilbertEric D. JoseckJean P. Andre
History of Lubricants and Basestocks
Lubricants Have Been Used Since Ancient Times
Initial Processing Was Limited To Separation By Boiling Point
The Petroleum-based Lubricants Business Began In The Mid-1800’s
Base Oil Quality Has Evolved With Process Technology
First Generation Process Technology Developed To Remove Aromatics, Other ImpuritiesSolvent Processing Technology Developed
Lower cost to operateDewaxing to lower pour point (and recover wax as a byproduct)Simple hydrofining also added to further reduce impurities
Hydroprocessing Technology Changed Base Oil Business From “ Physical Separations” To “Chemical Transformations”
Base oil quality drivers for lighter viscosity grades and refinery economics are making Hydroprocessingpopular option
Wax Isomerization Can Produce Very High Quality Base Oils
GTL wax derived Base oils
Key Lube Oil Properties
Viscosity (Measure of Fluidity)Range from ~ 4 to 20 cSt @ 100oC for Neutrals up to 32 cSt for Bright StockBrookfield Measures Low Temperature Fluidity on Finished Oils @ -40oC
Viscosity Index (Inverse Measure of Change of Viscosity with Temperature
Ranges from ~85 to ~105 for most Basestocks, Higher for Speciality Grades (ex: PAO ~150, XHVI~140+)
Pour Point (Temperature at Which Fluid Becomes Nearly Solid)Typically from -9 to -24oCCloud Point is Temperature at Which Wax Crystals Appear
Volatility (Measure of Oil Loss Due to Evaporation)Noack Volatility Measures Actual Evaporation (Typically 20-35 wt%)GCD Volatility Measures Front End of Boiling Curve (e.g 10% @375oC)
Color (Appearance) and Stability (Measure of Color Change in Light,...)Con Carbon (Measure of Carbon Residue Left on Ignition)Saturates, Aromatics and Asphaltenes Contents
Base Oil TerminologyLubes are High Value Products with Broad Variety of Uses
Automotive: Engine oils, Automatic Transmission Fluids (ATF)Industrial: Machine oils, Greases, Turbine oils, Electrical oils, Drilling FluidsMedicinal: Food Grade oils, White oils,..
Refineries Produce Base Oils or BasestocksFinished Products are Blends of Basestock with(out) Additives
Basestocks are Called by Various Names:Neutrals (100N, 150N, 600N,...)Bright StocksGrades (SAE 5, 10, 30, ..; ISO 22, 32,...)
Most Common Lube Name is NeutralNumber is the Viscosity @ 40oC
Bright Stock is Heavy Lube Made From ResidName Refers to Appearance and Typical Viscosity is 2,500 SUS @ 40oC
Grade Names May Refer to Viscosity or to Trademarks
Base Oil Production Economic Factors
Overall Refinery Economics Dictate Crude SelectionSolvent Lube Plants Often Limit Crude ChoicesCatalytic Lube Plants Allow More Flexibility In Crude SelectionLube And Fuel Plants Compete For Same FeedsHigh Crude To Fuel Margins Can:
Cause A Lube Refinery To Shutdown Or Lower ThroughputChoose To Operate The Catalytic Lube Plant For Fuels Production
Solvent Lube Plants Inherently Have High Operating Cash CostsEnergy, Solvent Usage, Labor, Size, Etc.
Cru
de/V
acuu
mD
istil
latio
nC
rude
/Vac
uum
Dis
tilla
tion
Solvent Lube Plant
Catalytic Lube Plant
Fuels Plant (HDC or FCC)
Crude
Group I
Group IIIGroup II,
Fuels by product
Gasoline & Diesel
Traditional Base Oil Production
Uses Solvent Extraction (Furfural or NMP) and Solvent Dewaxing (MEK)
Waxy Raffinate
Solv
ent D
ewax
ing
Hyd
rofin
ishi
ng
Prop
ane
Dea
spha
lting
AtmosphericResid
Fuels
IntermediateTankage
VacuumDistillation
Solv
ent E
xtra
ctio
n
Solvent I
Solvent Recovery
Solvent
Wax
D
eoili
ng
Wax
H
ydro
-fin
ishi
ng
Wax
Light
Medium
Heavy
BrightStock
Light
Medium
Heavy
BrightStock
Recent Quality Trends for Automotive Lube Grades is Putting Pressure on Conventional Solvent Based Plants
Properties Set by Units
Flash PointKV / Noack
Viscosity Index Pour Point ColorStability
Quality Drivers For Modern Basestocks
Basestocks Base OilAdditives
Good StabilityDrain Interval
Low VolatilityLow Emissions
Low ViscosityFuel Economy
Desired Basestock QualityPerformance Parameter
Finished Lube
Base Oil Grouping (API)
80 < VI < 120% Sat < 90%% S > 0.03
Group IGroup I80 < VI < 120% Sat < 90%
% S < 0.03
Group IIGroup IIVI > 120
% Sat > 90%% S < 0.03
Group IIIGroup IIIPAOs
Group IVGroup IV
Solvent RefiningCatalytic Hydroprocessing
Chemical Rx
OTHERS(E.g. Synthetic
Esters)
Group VGroup V
Chemical Rx
Very WideChemicalSpectrum
Single Component
Basestock Composition Determines Performance of Finished ProductsViscosity Index or VI (Higher VI improves Volatility, Fuel Economy, and Operating Range)Saturate Content (Higher Saturates improves Oxidation Stability and Soot Handling)Wax Content (Lower Wax Improves Operating Range, Low TemperaturePerformance, Pour Point, Cloud Point
99
40
15
1
Noa
ck V
olat
ility
, wt%
Molecular Type Links VI, Viscosity, Volatility
Viscosity, cSt at 40°C
350
400
450
500
550
10 100 1000
MA
BP,
°C
(VI) (170) (140) (100) (80)
(40)
(0)
(-100)
WAX: n-ParaffinVI > 200, but SOLID
Source: API Research Project 42, 1966
Volatility Has Become a Driver For Group III
Group I / Group II 95 VI
Group II+
Mid Tier Group III
Top Tier Group III+
Vola
tility
, %
5
10
15
20
Viscosity @ 100°C, cSt
4 5 6 7 8
Group IV / PAO’s
Primarily for automotive applications
Paraffins
Naphthenes Aromatics
Processing To Reduce Naphthenes and Aromatics
Higher Paraffin Content Results in Higher Viscosity Index (VI)VI is a good surrogate for many performance characteristics
Viscosity Index
Group II Gas Oil
Group IGroup III
PAO
Base Oil Manufacturing
GroupI/II
CatalyticDewaxing
GroupII/III
IsomerizationDewaxing
LubeHydrocracking
LubeHydrotreating
FuelsHydrocracking
GroupI/II
SolventDewaxing
SolventExtractionDistillation Finishing
Deasphalting
Lube Oil Chemistry
Complex Relation Between Molecular Composition and Properties Leads to Large Variety of Process Configurations Comprising Multiple Stages:
Deasphalting: Remove Condensed Multi-Ring AromaticsImproves Con Carbon, Stability and Color
Solvent Extraction or HydrocrackingRemoves Aromatics by Extraction, Hydrogenation or Dealkylation
Hydroprocessing: Remove Sulfur/Nitrogen and Hydrogenate Aromatics
Lowers Pour, Improves VI and StabilityNitrogen Leads to Low Stability, but Sulfur Acts as AntioxidantNaphthenics Improves Pour PointRemoves Napthenic Acids
HydroisomerizationImproves Pour Point of Paraffins
DewaxingRemoves or Converts High Pour Point n-Paraffins
Deasphalting
Required to Produce Bright Stock Base OilsWell-Known, Conventional Technology
Commercialized before WWII
SolventDewaxing
SolventExtractionDistillation Finishing
Deasphalting
Removes CCRRemoves MetalsRemoves Polars (i.e. Sulfur, Nitrogen)Reduces ViscosityDAO Becomes Viable HDC Feedstock
AsphaltenesPrecipitated from Crude Oils by Aliphatic Solvents (e.g. n-C5). Soluble in Benzene. Mol. Wt. 1000-3000. High in S, N, O, and Metals (V + Ni).
S
S
O
H
O O
N
N
C84H98N2S2O31248 Mol. Wt.40.4% Aromatic Carbons
80.85 wt%C7.92 wt%H2.24 wt%N5.14 wt%S3.85 wt%O
Asphaltenes: Materials With Complex Structures
Typical Contaminant Distribution in ROSE DAO
% COMPONENT IN DAO100
80
60
40
20
00 10 20 30 40 50 60 70 80 90 100
DAO YIELD, VOL %
METALS
SULFUR
NITROGEN
CCR
ASPHALTENES
Propane Butane Pentane
DAO Properties
Vac Resid DAO
API 8.7 21.6
KV@100C 1139 61.22KV@40 C 410.1 389.15
Sats,% -- ~70
Sulfur,wt% 2.77 1.41Nitrogen,ppm - 1000
CCR,wt% 20.6 3Ni,ppm 62 2.5V,ppm 98 1.5
Extraction
Removes Aromatics and Polar Components Proper Extraction Unit Operation is Critical to Meet Base Oil VI, Stability and Solvency SpecificationsYields are Crude Dependent but Typical Yields Around 70% for 95 VI. Higher VI Lowers Yields.
SolventDewaxing
SolventExtractionDistillation Finishing
Deasphalting
Solvent vs. Catalytic Dewaxing:
Solvent Dewaxing – Physically Separates Wax from Base Oil
Removes Normal and High-Pour Branched Paraffins by Crystallizing WaxAlso Removes Some High-Pour Non-ParaffinsPour Point Reduction Limited by Refrigeration Capabilities
Catalytic Dewaxing - Converts Wax to IsoparaffinsRemoves Fewer Naphthenes than SDW / Product is Less ParaffinicPreferentially Removes Low Molecular Weight Normal and Near Normal ParaffinsPossible to Produce Very Low Pour Point Base Oils
Catalytic Dewaxing- MLDW™
Extraction MLDWTMDistillate
60-80% yieldVI uplift 20-100
70-90% yield
H2 consumption 100-400 scfb
Base Stock
Compared with Solvent Dewaxing, MLDW has:
A Different Dewaxing MechanismWaxes converted to Naphtha & DistillateCan produce very low pour specialty productsYields better than SDW
Less Environmental ConcernsLower Manpower RequirementsLower Operating and Investment Cost
MLDW Characteristics
Waxes are Selectively Cracked to Naphtha and LPG
Two Reactor Cascade SystemReactor 1: Zeolite catalyst for dewaxingReactor 2: Commercially available hydrotreating catalyst
Low Hydrogen Consumption
Cyclic ProcessReactor temperature increased during cycle to meet pour point spec.At end of cycle, catalyst is reactivated to restore activity
Can Process a Full Range of Basestocks
Replaces and/or Supplements Solvent DewaxingCan make ultra-low pour point basestocks
Especially Attractive Option for Bright-stock Production
Base Oil Manufacturing
GroupI/II
CatalyticDewaxing
GroupII/III
IsomerizationDewaxing
LubeHydrocracking
LubeHydrotreating
FuelsHydrocracking
GroupI/II
SolventDewaxing
SolventExtractionDistillation Finishing
Deasphalting
Hydroprocessing Reduces Sulfur, Nitrogen and Boosts VI
Group IIGroup III
All Catalytic Group II & Group IIILube Plant
Hydroprocessing(HDT/RHC/LHDC)Hydroprocessing(HDT/RHC/LHDC)
CatalyticDewaxingCatalyticDewaxing
HydrofinishingHydrofinishing
0
20
40
60
80HDC
LHDC
RHC
HDT
Fuels Manufacture Hydrocracking
Lube Manufacture Hydrocracking
Raffinate Hydroconversion
Raffinate Hydrotreating
Conversion to 360O CBase
VI In
crea
se
Lube Hydrocracking
Production of Lube by Hydrocracking May be Carried in Conjunction With Fuels Production or be Solely Dedicated to Lubes
Lubes yields tied to yield of 375oC+ (20 to 40+ Carbons)VI uplift critical to production of high quality lubesConversion to fuels is controlled by the catalyst acidity
Hydrocracking Chemistry is Complex and Involves:Heteroatom removal (S, N)Aromatics hydrogenationAromatics dealkylationNaphthene cracking
Typical Operating ConditionsLHSV 0.5 to 1.0 h-1
Temperature ~ 400oCH2 pressure > 100 atmTreat Gas Rate 5,000 to 10,000 SCF/bbl
Lube Hydrocracking (Cont.)
H/C Catalysts are BifunctionalHydro-dehydro function provided by NiMo or NiW in sulfidedformAcid function provided by Amorphous Silica-Alumina or Zeolite
Large pore Zeolite such as HY, composited with a matrix/support
Metal/Acid Balance is Tuned to Selectively React Cyclic Molecules While Preserving Paraffins
Results in significant increase in VIConversion of aromatics to naphthenes to fuelsIncreased concentration of paraffins in lubes
Hydrocracking vs Solvent Extraction Results in Higher Lube Yields, Rich in Naphthenic Species
Maximizing Use of Existing Group 1 Equipment
Extraction HDT orRHCTM
Catalytic DewaxingDistillate
SolventDewaxing
70-80% Yield
50-70% yieldVI uplift 10-
35
80-98% yieldVI uplift 5-20
85-97% yieldVI uplift 4-10
300-600 scfb 100-400 scfb
Base Stock
Base Oil Manufacturing
GroupI/II
CatalyticDewaxing
GroupII/III
IsomerizationDewaxing
LubeHydrocracking
LubeHydrotreating
FuelsHydrocracking
GroupI/II
SolventDewaxing
SolventExtractionDistillation Finishing
Deasphalting
Catalytic Dewaxing
Primary Function is to Improve Cold Flow Properties of LubesBy removing or converting n-paraffins
Decrease pour point and cloud point
Development of Catalytic Dewaxing is Tied to the Discovery of Medium Pore Zeolites :
Control of acidity by de-alumination or al substitutionSteam treatmentAcid extraction
Shape selectivityAbility to selectively reacts molecules with smaller critical sizes
Paraffins < Isoparaffins << Naphthenes and AromaticsDiffusion/adsorption control in microcrystalline materials
Hydro-Dehydro Metal FunctionImpacts severity of processing conditions
Catalytic Dewaxing: Shape-Selectivity in Action
Performance Influenced by Choice of Zeolite
AcidityCrystal size and morphologyPore size and shape
MLDW™Primarily crackingNo noble metals
MSDW™Primarily isomerizationNoble metals catalyst
n-Decane Conversion (%)is
o-D
ecan
eYi
eld
(%)
0
20
40
60
80
100
0 20 40 60 80 100
MSDW™MLDWMSDW™MLDW
Lube Hydrocracker with MSDW™
Lube Hydrocracker MSDWDistillate
60-80% yieldVI uplift 20-100
85-97% yieldVI uplift 4-10
H2 Consumption 100-400 scfb800-2000 scfb
Base Stock
MSDW-2 MLDW(Isomerization) (Cracking)
Pour Point, °C -15 -15KV @ 100°C, cSt 5.03 5.57Viscosity Index 113 102Lube Yield, wt% 94.2 75.9
Historically MSDW preferred for lighter viscosity grades
Flow Diagram For DAO Hydrocracking
VGO/DAO
Hydrogen Feed
Low Temp.Separator
Steam
HighTemp.Separator
Reactor
LeanAmine
RichAmine
Off-Gas
Stripper
RecycleCompressor
Fractionator
Gasoline
Naphtha
Kerosene
Diesel
Steam
WaxyBasestocks or FCC Feed
HDC Reaction Zones
Reactor Catalyst HDCConfiguration Type Reactions
Metal
Bifunctional(Metal + Acid)
TreatingZone
CrackingZone
HDM
HDN
selectivecracking
with low arosat
Sulfur polishingIf needed
Post TreatZone Metal
HDS
HDA
Bright Stock made from Hydroisomerization (MSDW) and Catalytic Dewaxing (MLDW)
MSDW MSDW MLDW MLDW (est)Case 1 Case 2Gr II Gr I+ Gr I Gr I+
Color 13 saybolt -9 saybolt 2.5 astm 3.5 astmPour,C -14 -7 -6 -6Cloud,C -1 3 -KV@100C 29.9 29.1 31.86KV@40 C 410.1 389.15 486.73API - 27.7 25.3density@70C 0.8508 0.8552 -Sats,% >90 78 ~60Sulfur 85ppm 639ppm 1.2wt%Nitrogen,ppm <1 16 145VI 102.5 103.4 96
102Haze no no noYield,wt% 75 83 85-90 78Extract. yield, wt% 71 71 71 20MSDW can allows BS Production by all Hydroprocessing Route
MSDW-2 Pilot Study on Hydrocracked DAO
20
40
60
80
0 50 100 150 200 250Time on stream, days
Dew
axin
gT
empe
ratu
re, °
C
22 ppm N, 150 ppm S0.14% CCR24 ppm N, 280 ppm S
0.06% CCR
2 ppm N8 ppm S
2 ppm N18 ppm S
160 ppm N, 700 ppmS, 0.57% CCR
Base
+
+
+
+
HDC HVGOfeed 1 -reference
HDC DAOfeed 2
HDC DAOfeed 3
HDC DAOfeed 4
HDC DAOfeed 5
MSDW catalyst is tolerant to poisons and maintains activity
Feed # 2 3 4 5HDC Severity High Low High Low
MSDW FeedkV@100°C, cSt 10.3 18.9 12.8 23.5Nitrogen, ppm 2 24 22 157Sulfur, ppm 8 283 146 704CCR, wt% 0.01 0.06 0.14 0.57
MSDW Product (Bottoms Fraction)kV@100°C, cSt 20.7 28.9 24.1 40.1VI 120 100 107 93Pour point, °C -14 -11 -2 -8
DAO BDAO A
MSDW-2 Pilot Study on Hydrocracked DAO
MSDW Advantage: Bright-Stock Production
0
10
20
30
40
50
60
70
KV@100C
1000 90 33 8 3
Nitrogen,ppm
Increasing LHDC Severity---->
010
203040
50607080
90100
B.S. Yield, wt%
1000 90 33 8 3
Nitrogen,ppm
Increasing LHDC Severity---->
Combined HDC/MSDW Performance
MSDW can tolerate higher levels of Nitrogen allowing improved yields and blending flexibility
All Hydroprocessing option for Bright-Stock Production
High Throughput Experimentation Accelerating Catalyst Innovation
Analysis
ExperimentalDesign
Automation &Robotics
High SpeedAnalysis
DatabaseManagement
Informatics
Robotics
Analytics
1 2
3 4
5
6
A
B
C D E F G I0.E+00
4.E+05
8.E+05
1.E+06
2.E+06
Mw
Activator Catalyst
Copyright 2002 Symyx Technologies, Inc. Used with permission.
R&D Focus is to Develop More Active/Selective Catalysts
Activity/Selectivity
Time
Dewaxing:MSDW/ MLDWHydrofinishing:MAXSAT™
60
80
100
200 240 280 320 360 400Temperature, °C
Estimate of Equilibrium Saturates
400 psig, H2
600800
12001800
Satu
rate
s, w
t%
Why Hydrofinish?Removes Polynuclear Aromatics (PNA) and Trace Amounts of OlefinsImproves Color, Oxidation and Thermal Stability of Base OilsPNA Equilibrium Concentration Controlled by Reaction Temperature and Pressure
Aromatic Saturation
0
2
4
6
8
0 20 40 60 80
Relative Temperature
Rel
ativ
e A
rom
atic
s KineticcontrolEquilibriumControlKineticControlEquilibriumControl
High Activity Catalyst Can Provide Significant Advantage
Increasing Pressure
MSDW Base Oil Production
Hydrocracked Light Neutral FeedstockHydrocrackedHydrocracked Light Neutral FeedstockLight Neutral Feedstock
Yiel
d W
t, %
Yiel
d W
t, %
MSDW-2MSDW-2MSDW-1MSDW-1
SolventSolvent
75
80
85
90
95
100
-50 -40 -30 -20 -10 0 10100
104
108
112
116
120
-50 -40 -30 -20 -10 0 10Pour Point, ºC Pour Point, ºC
VIVI
MSDW-2MSDW-2
MSDW-1MSDW-1
SolventSolvent
Increase Selectivity/ ActivityIncrease Selectivity/ Activity
Direct Isomerization of Slack Wax to High Quality Lubes (MWI™ - Process)
Hydro-Isomerization
Slack Wax
50-70% yield130 to 160 VI
H2 Consumption 200 - 400 scfb
Basestock
Technology for Converting Methane to Liquid ProductsFischer Tropsch Products Have Virtually No Impurities
Essentially Sulfur- and Nitrogen-freeVery low aromatic content High-Quality Ultra
CleanProducts, Incl. Fuels and Lube
Basestocks
Syngas Generation
Hydrocarbon Synthesis
Product Upgrading
GTL Process
Natural Gas
Steam
Oxygen Wax
GTL Basestocks Expected to Be Highly Paraffinic
GTL VI Could be Comparable to PAO of Similar Viscosity
Paraffins
Gas oil
Group I
Group II
Group III
PAO
Naphthenes Aromatics
Viscosity Index
GTL
Vola
tility
5
10
15
20
Viscosity @ 100°C, cSt4 5 6 7 8
GTL Lube Basestocks
GTL Basestocks Performance May Approach That of Chemically Derived PAO
Group I / Group II 95 VI
Group II+
Mid Tier Group III
Top Tier Group III+
Group IV / PAO’sGTL?
Conclusions
MLDW Catalytic Dewaxing is Excellent for BS Manufacture at Conventional VI Levels for Group I With Yields Equal or Better Than Solvent Dewaxing.Hydroisomerization (MSDW) is Excellent for Higher VI BS and Group II BSMSDW’s Polar Tolerance Allows Excellent YieldsImproved Catalysts (Activity/Selectivy on the Horizon)Integrating Catalytic Hydroprocessing/Dewaxing Can Extend the Asset Life of Conventional Solvent Based Lube Base-Oil PlantsExxonMobil Technologies Provide Competitive Advantage in Broad Range of Solutions
Wax Hydrosomerization1991
MSDW-11997
Raffinate Hydroconversion1999
MSDW-21999
Lube Hydrocracking1923
MAXSAT2001
Lube Dewaxing(MLDW) 1981
Fuels HDC BTMs toLubes 1989
Wax Hydrofining1953
Lube Hydrofining1954
White Oils1973
70 Years of ExxonMobil Innovation in Catalytic Lube Processing –
Catalyst Improvements being rolled out