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.