Natural Oils – The Next Generation of Diesel Engine Lubricants?
JOE PEREZ1 & SHAWN WHITACRE2
1The Pennsylvania State University2National Renewable Energy Laboratory
USDOE DEER 2002 Conference, , San Diego, CA (August 2002)
OUTLINE
• Introduction• Current Technology
– CI-4– Environmentally Acceptable/Friendly Fluid
• Renewable Technology and Resources• Experimental Progress• Needs
INTRODUCTION
Future Diesel Engine Emission Regulations –• Ultra-low Sulfur Fuels• Aftertreatment Systems• Catalyst Compatible Engine Oil
Aftertreatment Poisoning• Efficiency and Life• Metals• Sulfur, Phosphorus
0
70
R2 = 0.9443
R2 = 0.3289
0 6.5 7.2 8.8 9.3 10.4 15.4
Phosphorus, grams
% c
han
ge
afte
r w
ash
HC NOx
Effect of Phosphorus on Hc and NOx Emissions –Change after Catalyst Oxalic Acid Wash
From “Future Engine Oil Trends”, Filter Technology Workshop, Stefan Korcek, Ford, (May 2001)
Additive Conc. vs Miles
0500
1000150020002500300035004000
0 44.5 81.6 100
Oil Miles, Thousands
pp
m SulfurPhosZinc
(EDI Oil analyses –Samples from same truck)
Introduction (continued)
• “Evolution” versus “Revolution”• CI-4 : Evolution • PC-10 : A Quantum Jump
Evolution of Diesel Engine Oils
API Designation YEAR No. of TESTS TO QUALIFY OIL
Purpose or Reason for Change
CD PRIOR 1988 2 Deposits/Corrosion
CE 1988 5 Oil Consumption
CF-4 1990 5 Fuel Efficiency/PM
CG-4 1995 8 PM & S Reduction
CH-4 1999 12 NOx Red’nHigh Soot
Extended ODICI-4 2002 15 Cooled EGR
(PC-10) 2007 ? Aftertreatment
CURRENT TECHNOLOGY
API CI-4Designed to meet needs in 2002
• Increased soot and corrosion related wear • Changes in viscosity due to increased soot• Oxidative thickening due to higher temperatures• Oil consumption control• Foaming, seals, viscosity loss due to shear
API CI-4 ENGINE TESTS and PURPOSE
ENGINE TEST PURPOSE Comments
Caterpillar 1R Piston Deposits, Oil Consumption
Two – piece Piston
Caterpillar 1K or 1N Piston Deposits, Oil Consumption
Aluminum Piston
Mack T-10 Ring, liner, bearing wear, oil consumption
Cooled EGR
Mack T-8E Viscosity Increase Due to 4.8% Soot
ASTM D5967
Cummins M11-EGR Ring & Valve Train, Wear, Sludge & Filter Plugging
Cooled EGR
International 7.3L EOAT Aeration HEUI Injectors
GM 6.5 liter Roller-Follower Wear ASTM D5966
Sequence IIIF Oil Oxidation ASTM Seq. IIIF
API CI-4 Bench Tests and Performance Criteria.
TEST PURPOSE COMMENT
BOSCH INJECTOR HIGH TEMPERATURE –HIGH SHEAR
BOSCH INJECTOR SHEAR STABILITY ASTM D6278
MINI ROTARY VISCOMETER TP-1
LOW TEMPERATURE PUMPABILITY, SOOTED
OILS
ASTM D4684
NOACK OIL VOLATILITY ASTM D5800
CUMMINS BENCH TEST
CORROSION ASTM D6594
FOAMING TEST FOAMING ASTM D892
ELASTOMER COMPATABILITY
REF. OIL TEST
ELASTOMERCOMPATABILITY
ASTM D471
A related issue is whether renewable, natural oils can be used as the primary base fluid for future diesel engine oils.
Environmentally Friendly Base Oils
Biodegradable, Low ToxicityAnd
A Renewable, Natural Product
Advantages & Disadvantages
Advantages: Disadvantages: • Very High VI
• Biodegradable
• Non-toxic
• Renewable
• Domestically Produced
• Oxidation Stability
• Low Temperature Properties
• Hydrolytic Stability
• Availability
• Unproven Performance
• Cost
OXIDATION STABILITY
S t r u c t u r e s a n d P r o p e r t i e s o f S o m e U n s a t u r a t e d F a t t y A c i d s
# o f C a r b o n s M P , C
4
- 5
- 1 1
1 8
1 8
1 8
O
O H
o l e i c a c i d
O
O H
l i n o l e i c a c i d
O
O H
l i n o l e n i c a c i d
PSMO Oxidation Test
EVAPORATION
A B C DeposA B C Deposits its
A’ B’ C’
Volatile Thermal – Oxidative Products
A” B” C”
PSMO PSMO Deposit Formation ModelDeposit Formation Model
Oxidation Stability - Chemical Modification
0
10
20
30
40
50
60
70
80
0 30 60 90 120 150
Time (min)
% In
solu
ble
dep
osi
t
SBO
HOSBO
ESBO
Oxidation Stability - Additives
0
10
20
30
40
50
60
70
80
0 30 60 90 120 150
TEST TIME, min
% D
EP
OS
ITS
wo Adds.
AO1+AO2
AO 1, 2+3
Laboratory
Vehicle –Used Oils
GPC - Analyses of Oxidized Oils
Wear – Soybean Oil
0
0.05
0.1
0.15
0.2
0.25
0.3
30 60 90
TEST TIME, min
∆ S
CA
R, m
m
none
1%add5
1%add6
2%add6
Fuel vs Available Vegetable Oil, Millions of Gallons per Year.
RequirementFor
TOTAL DIESEL FUEL (1995)
TOTAL VEGETABLE
OIL (1985)
19% OIL YIELD
AMOUNT REQUIRED
for B20
AMOUNT 2% Veg Oil in Oxidized
Fuel as Additive
U.S. 35,000 4616 877 7,000 840
World 187,000 12,475 2,370 37,400 3,740
Sources: www.bp.com,www.chevron.com, K. Wain PSU MS Thesis
Questions Answers
1. Level of ZDTP ?2. Wear and Durability?3. Adequate Friction?4. Natural Resource
Oils - Performance?5. Adequate Resources?6. Standardization –
Specifications7. PC-10
1. Emission & Catalyst data and analysis.
2 & 3. New Additive Technology.
4. Oxid’n & Hydrolytic Stability, Low Temp.
5. Higher Productivity6. Team Effort7. CI-4 Team Repeat
Needs – Recommendations:• Quantitative data on aftertreatment poisoning,
• Standardization – specifications for renewable oils,
• Total refinery concept – Optimize product quality,
• Continued research – Genetic & Chemical Modification and Additive Technolgy
• Evaluation of new products for PC-10 (performance and cost).
ACKNOWLEDGEMENTS• NREL• USDOE• Contributors to this STUDY especially, A. Adhvaryu, K.
Cheenkachorn, W. Lloyd, L. Rudnick, K. Wain (all from PSU), F. Kelley (consultant), G.Kling (Caterpillar –Retired,),
• and the many individuals with whom this subject was discussed or from whom copies of presentations were received, including E.Bardasz, D. Burke, B.Bremmer, S.Erhan, S.Gunzel, W. Kieser, D. Kodali, J. Krahl, F.Lockwood, I.Rhee, B. Rhodes, S.Schwartz, R. Shah, D.Smith, W.Sumi, and others.