Joseph M. Perez, Tribology Group, Chemical Engineering Dept.,
Penn State University, University Park, PA 16802
Diesel Engine Emissions Reduction ConferenceNewport, RI
August 24-28, 2003
Research on Fuels & Lubricants
Penn State’s Slippery Bunch:
1950’s Dew Line Lubricants, New Base Oil & Additive Technology
1960’s SR 71 Blackbird Hydraulic Fluids, Super Refined Lubricants (Type II)
1970’s Oxidation, Greases, Metals1980’s VPO, Adiabatic Engine, MeOH Oils1990’s Environmentally Friendly Fluids
Extended Drain Oils
Current Projects
Fuel StudiesDMEBiodieselULSF
Vegetable OilsHigh Temperature Liquid LubricantsCoatings & LubricantsRole of Chemical Structure
Penn State “Green” Project
1. Over 200 pieces of farm & construction equipment on campus.
2. Conversion to Environmentally Friendly Lubricants initiated.
3. Use of Biodiesel in farm equipment.4. Conversion of waste oils to Biodiesel –
Undergraduate Engineering Project
FUELSDiesel Fuels
Biodiesel Fuels
Dimethyl Ether
+ ROH catalyst
Hydrocarbon Syngas DME
Distillation Hydrocarbon mixture
Soybeans
Petroleum cut boiling ~ 282-338oC, #2, LSDF and ULSDF
300 ppm S32 ppm SULSD (< 15ppm S)
Blends of methyl esters made from vegetable oils
Converted from Syngas
DME Methane + H2 + CO
DME Research
DME is environmentally benignDecomposes rapidly Doesn’t harm ozone layer
Reduces diesel engine emissionsAddition of oxygen into combustion zone
Engine and Vehicle TestsProblems include low viscosity (wear), high vapor pressure, and material compatibility
Laboratory TestsViscosity StudiesInjector StudiesO-Ring Studies
Fuel Injector Studies
Need digital pics of new andDME pins from Plint!
Dr. Perez has pins at Argonne
New DME SCUFFED
Fuel Injector Pin
Modified Cameron –Plint Machine
Test Pins
Biodiesel Fuel Studies
Previous work involved study of VPO of diesel and biodiesel fuels in pilot plant (10)
(10) Wain, K. Perez, J. “ Oxidation of Biodiesel Fuels for Improved Fuel Lubricity” Proceedings of the Internal Combustion Engine Division, Lubrication and Friction Committee ASME Rockford, IL #2002-ICE-447 (2002)
Demonstrated in laboratory tests that addition of oxygen to biodiesel resulted in improvement in friction
Run #1Temp- 325oC
Feed Rate- 1000 g/hr
O2/Feed Mole Ratio- 1.0
Run #2Temp- 375oC
Feed Rate- 1000 g/hr
O2/Feed Mole Ratio- 1.0
0.020
0.040
0.060
0.080
0.100
0.120
0.140
0 10 20 30 40 50 60Time (min)
Fric
iton
Coe
ffici
ent (
)
Low Sulfur Diesel
Ox. Diesel Run #1
Ox. Diesel Run #2
Low Sulfur & Oxidized Diesel Fuels
0.060
0.070
0.080
0.090
0.100
0.110
0.120
0.130
0.140
0 10 20 30 40 50 60
Time (min)
Fric
iton
Coe
ffici
ent (
)
Fuel A
Fuel B
Fuel C
Friction Traces for [email protected]
Fuel Deposit TestsMicro-oxidation test
10ml of test fuel into glass test tubeOne stainless steel panHeat to 150oC for 7 daysWeigh and characterize deposits on pan
Test Fuels
A,B,C Ultra low sulfur fuels, different manufacturersD Low sulfur dieselE KeroseneG #2 diesel
Fuel also filtered through Al column to remove additives and analyzed
Fuel Deposits
*Filtered fuel shows little or no deposits on walls of glass micro-oxidation tubes as well as on coupons
Progressively less deposits as B is
filtered
Progressively less deposits as G is filtered (not as dramatic as B)Order of deposit
thickness, most to least: B>>A>D>C G>E
0
5
10
15
20
25
30
35
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Carbon #
Rel
ativ
e %
Fuel AFuel BFuel G
GC Analyses - Fuels
Fuel C, D similar to A
Fuel B significantly different - additive?
Does the Chemical Structure of the Base Fluid affect its effectiveness in protecting the surface against wear?
Lubricant Research
Effect of Structure
Alcohol + Acid Ester + Watercatalyst, heat
To evaluate structure effect use same acid (2-ethylhexanoic) and different alcohols
Neopentyl Glycol
Trimethylol propane
Pentaerytritol
(CH3)2C(CH2OH)2
CH3CH2C(CH2OH)3
C(CH2OH)[email protected]
0
0.05
0.1
0.15
0.2
0.25
0.3
Wear
∆ S
CA
R
Ester D Ester E Ester F
Effect of Acid Chain Length on Wear
Trimethylol propane = alcohol
Acids:
D = nC5
E = nC7
F = mixture of nC8 & C10
Wear Index =
(Total Carbons)(Effective Chain Length)(Polar Value + Branching Value)
where:Total Carbons = total carbons in the molecule
Effective Length = longest free chain of carbons available to form a film.
Polar Value = No. of carboxyl groups + No. of hydroxyl groups
Branching Value = ( 0.5 x No. of branches) + No. of double bonds.
WEAR INDEX vs WEAR RATE
R2 = 0.7934
0
10
20
30
40
50
60
0 50 100 150 200 250 300WEAR INDEX
WEA
R R
ATE
, mm
3/N
mX1
0-9 Wear Rate
Log. (Wear Rate)
TEST COND: 40kg, 75C, 600rpm, 30min
EFFECT of CHAIN LENGTH on FRICTION COEF.
R2 = 0.9622
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
0 5 10 15 20 25
ESTER ACID CHAIN LENGTH, CARBON No.
FRIC
TIO
N CO
EF.
TEST CONDITIONS: 40 kg, 75 C., 600 rpm, 30
Test ConditionsFour Ball Wear Tester:
ANSI 52100 stainless steel balls
Test Time:30 min Run-in30 min Steady State 30 min Surface Eval’n
Test temp. = RT, 60oC, 75oC
Speed = 600, 1200 RPM
Loads = 1,10, 40 Kg
Pin – on – Disc:
Variable SpeedVariable Load
This study: 10 RPM20 NRoom Temp.
254
91
66.8
8.29
Oil C
>>200226219Flash Point, oC(ASTM D 92)
12097123Viscosity Index(ASTM D2270)
21528.816.9cSt Visc @ 40oC
24.44.993.9cSt Visc @ 100oC (ASTM D 445)
OIL DOil BOil AOilProperties
Properties of Test Oils
0
0.05
0.1
0.15
0.2
0.25
0.3
∆ w
ear,
mm
Run-in St.State Film Eval
Test Segment
Oil AOil BOil COil D
Effect of “Chain Length” of Hydrocarbon Oils on Wear – 4Ball Test
0
1
2
3
4
5
6
7W
ear
Rat
e m
m/N
m x
10-
09
Wear f x 100
Oil AOil BOil COil D
Effect of Oil “Chain Length” –Tribometer (CSEM)
Fric t ion coeffic ient of HMW Synth - Veg O il without ant iwear addit ive
0.0000
0.0200
0.0400
0.0600
0.0800
0.1000
0.1200
0.1400
0 30 60 90
T ime (min )
Wear Scar = 0.44 mm
∆ Wear Scar= 0.140 mmFC= 0.0902
Wear Scar = 0.61 mm
∆ Wear Scar= 0.12 mmFC= 0.0926
Wear Scar = 0.490 mm
∆ Wear Scar= 0.05 mmFC= 0.0832
Pin-on-Disc Avg f =0.066
R2 = 0.7764
00.05
0.10.15
0.20.25
0.30.35
0.40.45
0 2 4 6 8
Pin on Disc Wear
Four
-bal
l Wea
r
Effect of “Chain Length” of Hydrocarbon Oils on Wear – 4Ball Test vs Tribometer
0
0.05
0.1
0.15
0.2
0.25
0.3
∆ W
ear,
mm
Run-in Steady State Film Eval
ESBOSBOHOSBO
Effect of Double Bonds – Veg Oils
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
∆ W
ear,
mm
Run-in Steady State Film Eval.
SBO+ Add AESBO+ Add A
Additive Effectiveness - Additive A
00.020.040.060.08
0.10.120.140.160.18
0.2
∆ W
ear,
mm
Run-in Steady State Film Eval.
SBO+ Add AHOSBO+ Add A
Effect of Unsaturation - Additive A
0
0.05
0.1
0.15
0.2
0.25
0.3
∆ W
ear,
mm
Run-in Steady State Film Eval.
SBO+ Add BESBO+ Add B
Additive Effectiveness - Additive B
00.020.040.060.08
0.10.120.140.160.18
0.2
∆ W
ear,
mm
Run-in Steady State Film Eval.
SBO+ Add BHOSBO+ Add B
Effect of Unsaturation - Additive B
0
0.05
0.1
0.15
0.2
0.25
0.3
∆ W
ear,
mm
Run-in Steady State Film Eval.
SBO+ Add CESBO+ Add C
Additive Effectiveness - Additive C
00.020.040.060.08
0.10.120.140.160.18
0.2
∆ W
ear,
mm
Run-in SteadyState
Film Eval.
SBO+ Add CHOSBO+ Add C
Effect of Unsaturation - Additive C
SummaryEFF & L - research studies & demonstration projects. Oxygenated Alternative Fuels - reduce particulates. DME - potential wear problems. VPO Biodiesel - effective f & wear additive.ULSF’s – wear, deposits, filter plugging. Chemical structure of base fluids and additives -significant factor in future lubricant formulation. New test methods - key to understanding surface interactions. (Optical, Advanced Photon Source, etc.)Surface engineering–materials, coatings & lubricants.
AcknowledgementAppreciation is given for partial funding of these projects by Air Products; Cargill Corp; Caterpillar, Inc.; Cummins Engine Co.;USDA Laboratory (Peoria, Il) and Valvoline, Inc. Their financial support is appreciated.
A special thanks to Dr. George Fenske and the Tribology Group at Argonne National Laboratory for their continued interest and support of this research.
The research contributions of the following Graduate Students is acknowledged:
Penn State University: Kimberly Wain – Biodiesel Fuels, DMEElana Chapman–DME, Oxygenated FuelsWaleska Castro – Veg. Oils, f & wear testsKraipat Cheenkachorn – Vegetable OilsDavid Weller – Chemical Characterization
Northwestern University: Ashlie Martini - Pin-on-disc studies, Mark Sturino - Pin-on-disc studies, Optical Microscopy
Is Tribology Important?
Lack of Tribological Solutions results in Big Business:
1980 Survey - Over 20 Billion lost due to friction and wear annually
ASME Research Committee, circa 1980
1995 - Over 1.5% of the gross national product is lost due to friction and wear
Amato, Ivan, “ Better ways to Grease Industry’s Wheels” Fortune, Sept 1995; 256 [B]-256[K]
