Washington State DOT Biodiesel Workshop

Dr. Andrew McKnight Innospec Fuel Specialties

March 22, 2012

It Was a Warm Cold Winter!

* source: National Climatic Center/NESDIS/NOAA

vs. monthly average for 1981-2010 base period vs. monthly average for 1971-2000 base period

Temperature Anomalies -- January 2012*

Topics

!   “The Challenge of ULSD” !  Diesel Fuel Chemistry !  Effect of Fuel Composition on Low Temperature

Operability !  Cold Flow Improvers – How do they work? !  The Challenge of Biodiesel !  Washington State Winter 2011-12 Cold Flow

Performance

The Challenge of ULSD

ULTRA LOW SULFUR DIESEL

Polar Compounds

Aromatics / Olefins Saturated Hydrocarbons

Natural Biocides

Natural Stabilizers

Fuel Density

Caustic Carryover

Water Fallout LOW SULFUR DIESEL

The Challenge of ULSD What happened to the fuel during the conversion?

ULTRA LOW SULFUR DIESEL

Polar Compounds

Aromatics / Olefins Saturated Hydrocarbons

Natural Biocides

Natural Stabilizers

Fuel Density

Caustic Carryover

Water Fallout

Low

Tem

p O

pera

bilit

y

Cor

rosi

on

Mic

robi

al G

row

th

Con

duct

ivity

In-V

ehic

le S

tabi

lity

Lubr

icity

LOW SULFUR DIESEL

The Challenge of ULSD What happened to the fuel during the conversion?

ULTRA LOW SULFUR DIESEL

Polar Compounds

Aromatics / Olefins Saturated Hydrocarbons

Natural Biocides

Natural Stabilizers

Fuel Density

Caustic Carryover

Water Fallout

Low

Tem

p O

pera

bilit

y

Cor

rosi

on

Mic

robi

al G

row

th

Con

duct

ivity

In-V

ehic

le S

tabi

lity

Lubr

icity

LOW SULFUR DIESEL

CFI

The Challenge of ULSD What happened to the fuel during the conversion?

Diesel Fuel Chemistry

Diesel Fuel... ... Is a Mix of Several Types of Hydrocarbons

Selected Hydrocarbon Types

Paraffins Naphthenes Aromatics Olefins

n-Decane

iso-Decane

Butylcyclohexane

Decalin Naphthalene

Butylbenzene Heptene

Diesel Fuel Straight Chain Paraffins (Wax)

5 Carbons = C5

12 Carbons = C12

16 Carbons = C16

18 Carbons= C18

Diesel Fuel What Do We See When Paraffins Crystallize?

Heavy, large crystals

sediment and agglomerate at

the bottom of the tank where fuel

is drawn

Large paraffin crystals

can block filter pores

Wax can build up in sharp bends restricting flow

Diesel Fuel Where Does Crystallization Affect Vehicle Operation?

Diesel Fuel General Low Temperature Operability Terms

Cloud Point Untreated

CFPP Untreated

PP Untreated

Diesel Fuel What’s Really Happening When Paraffins Crystallize?

Super saturation / Nucleation

Cloud Point Visible Crystals

Existing Crystal Grow Additional Nucleation Occurs

Larger crystals begin to adhere along the

edges trapping liquid in “pockets”.

TEMPERATURE

Crystal growth

No Flow Point Pour Point

Fuel solid / gelled

13oF

10oF

7oF

0oF

CFPP ? > 0.4% wax

Morphology Phenomenon Observation

No Visible Crystals

Cold Flow Improvers What Affects Their Response?

Fuel Composition How Does it Affect Wax Crystallization?

!   Solvency of the Fuel –  Primary driver is “aromaticity” –  Higher aromaticity ~ more wax can

be dissolved at a given temperature

Aromatics

Naphthalene

Butylbenzene

Fuel Composition How Does it Affect Wax Crystal Growth?

!   Solvency of the Fuel –  How much wax can be dissolved at a given temperature

!   Total Wax –  How much precipitates between the cloud point and a given

temperature is a critical factor in Low Temperature Operability (LTO)

–  Higher wax content à more wax near the cloud point

0

2

4

6

8

10

12

14

16

18

20

0 25 50 100 150 200 250 300 350 400 450 500

Active Additive PPM

CFPP

(oC)

0.8%1.0%1.2%1.4%1.6%1.8%2.0%

75 ppm

110 ppm

+47% +16%

170 ppm

+126% +33%

275 ppm

+266%

+50%

Fuel Composition Total Wax Content

Fuel Composition How Does it Affect Wax Crystal Growth?

!   Solvency of the Fuel –  How much wax can be dissolved at a given temperature

!   Total Wax –  How much precipitates between the cloud point and a given

temperature is a critical factor in Low Temperature Operability (LTO)

–  Higher wax content à more wax near the cloud point

!   Wax Distribution –  The amount of each wax chain length relative to the other

waxes has a dramatic impact on wax crystal formation, operability at low temperature and ability to treat with CFI

Broad Wax Distribution

Increasing boiling point = increasing wax length

0

5

10

15

20

Normal 1.1 2 3.5 5.7 8.7 12.1 14.8 15.9 17.2 15.6 13 9.9 7.4 5.1 2.9 1.4 0.9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Narrow Wax Distribution

0

5

10

15

20

Normal 1.1 2 3.5 4.4 5.7 7.1 9 15.9 17.2 15.6 13 6.5 4.6 4.1 2.8 1.4 0.9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Heavy End Wax Distribution

0

5

10

15

20

Normal 1.1 2 3.5 5.7 8.7 12 15 16 16 16 13 9.9 7.4 5.1 2.9 2.5 1.8 1.5 1.3 1.1 0.8

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 26 27 28 29

!   Solvency of Fuel !   Total Wax

–  More wax requires more CFI

!   Wax Distribution –  No single CFI additive responds well in all diesel fuels. –  Additive structure and chemistry needs to be “tailored” to the

paraffin composition of the fuel to be treated

Fuel Composition Key Points

Cold Flow Improvers

How do they work?

Cold Flow Improver (CFI) Function

Cloud Point Untreated

CFPP Untreated

PP Untreated

Cloud Point with CFI

CFPP with CFI

PP with CFI

Allows operations lower than that of untreated fuels

improver

Polymer attaches to growing wax crystal surface and inhibits further wax deposition

Crystal Growth Modification ”Growth Arrest”

Form and size of n-paraffin crystals are influenced by adding CFI‘s

CFI

Crystallisation depends on type and amount of waxes as well as on the middle distillate oil matrix, e.g. aromatics, naphthenics

Crystal Growth Modification ”Growth Arrest”

–  Additive precipitates from fuel before n-paraffins –  Provides growth / nucleation site for precipitating wax molecules

Crystal Growth Modification ”Nucleation”

Nucleation and Filter blocking

Treated with Treated with MDFI Typical Anti-Gel/PPD

-80

-70

-60

-50

-40

-30

-20

-10

0

10

20

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Tem

pera

ture

(°F)

Percent #1 ULSD

Cold Flow Data for B5 Blends with #1 ULSD (ULSD source - Montana)

Cloud Point

CFPP

Effect of Kerosene on B5 CFPP

-80

-70

-60

-50

-40

-30

-20

-10

0

10

20

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

Tem

pera

ture

(deg

F)

Percent #1 ULSD

Cold Flow Data for B5 Blends with #1 ULSD (ULSD source - Montana)

Cloud Point

CFPP

CFPP with Cold Flow Improver

Effect of Kerosene vs Cold Flow Improver on B5 CFPP CFI much more effective

The Challenge of Biodiesel

Biodiesel Saturated Fat Content vs Cold Flow

0

10

20

30

40

50

60

70

80

90

100

Soy Corn Cotton Sunflower Lard Tallow Inedible Grease

Canola Coconut

% F

at

% unsaturated % saturated

Remember Narrow Wax Distributions?

0

5

10

15

20

Normal 1.1 2 3.5 4.4 5.7 7.1 9 15.9 17.2 15.6 13 6.5 4.6 4.1 2.8 1.4 0.9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26

Adding B100 Enriches Diesel in 16 and 18 Carbon Molecules

Melting Point of C18 Fatty Acids

Stearic Acid MP = 157 °F

Oleic Acid MP = 55 °F

Linoleic Acid MP = 10-23 °F

-25

-20

-15

-10

-5

0

5

10

ULSD B5 Soy B10 Soy B5 Tallow B10 Tallow

CFP

P (d

eg F

)

untreated

1000ppm

Soy and Tallow B100 in “easy to treat” N.E. U.S. ULSD Tallow most problematic, at 10%

-8

-6

-4

-2

0

2

4

6

8

10

ULSD B5 Soy B10 Soy B5 Tallow B10 Tallow

CFP

P (d

eg F

)

untreated

1000ppm

2000ppm

Soy and Tallow B100 in “hard to treat” N.E. U.S. ULSD

Low Temperature Operability of BX Blends

Cloud Point LTFT Untreated

CFPP Untreated

LTFT with CFI

Cloud Point LTFT Untreated

CFPP Untreated

LTFT with CFI

CFPP with CFI

LTFT Untreated

CFPP with CFI

-28

-26

-24

-22

-20

-18

-16

-14

-12 ULSD SME B2 CME B2 CME B5

Tem

pera

ture

oC

Cloud Point LTFT Untreated LTFT PL-2315.3 1175 mg/L Target CFPP Cloud Point LTFT Untreated CFPP Untreated

ULSD B5 SME B11 SME B20 SME

Illinois Winter Fuel

Washington State Winter 2011-12 Cold Flow Performance

-60

-50

-40

-30

-20

-10

0

10

20

-20 -15 -10 -5 0 5 10 15 20

CFP

P (°

F)

Cloud Point (deg F)

WA State Winter 2011-2012 Field Data UNTREATED Fuels

Untreated Diesel from WA State

-60

-50

-40

-30

-20

-10

0

10

20

-20 -15 -10 -5 0 5 10 15 20

CFP

P (°

F)

Cloud Point (deg F)

WA State Winter 2011-2012 Field Data UNTREATED Fuels

Roughly linear (CP = CFPP)

Untreated Diesel from WA State

-60

-50

-40

-30

-20

-10

0

10

20

-20 -15 -10 -5 0 5 10 15 20

CFP

P (°

F)

Cloud Point (deg F)

WA State Winter 2011-2012 Field Data

Treated Diesel from WA State

Untreated fuels

-60

-50

-40

-30

-20

-10

0

10

20

-20 -15 -10 -5 0 5 10 15 20

CFP

P (°

F)

Cloud Point (deg F)

WA State Winter 2011-2012 Field Data

Treated Diesel from WA State

Untreated fuels

Cold Flow Improver depresses CFPP ~ 25°F