Catalytic Conversion of Tall Oil to Renewable Diesel and Biodiesel

University of Louisiana at LafayetteChemical Engineering Department

Kiran Pathapati, Stephen Dufreche, Rakesh Bajpai, Mark Zappi

Source: U.S. Energy Information Administration, Annual Energy Review 2009

Why Biofuels? Forecasted shortages and increasing prices of fossil

fuels

Energy security

Economy

Environmental issues

Feedstocks are the Key Today’s popular feedstocks include sugars from

sugarcane, sugar beets, and sweet sorghum, along with starch from corn and wheat, and vegetable oil from soybeans or palm

Drawbacks: Combine to produce just 3% of today’s transportation

fuel requirement Biodiesel and Ethanol are competitive in the market

only due to subsidies Food vs Fuel Issues related to diesel engine performance

New Feedstock Alternative Abundant Renewable Non-food

Example: Tall Oil

A yellow-black, foul-smelling, homogeneous mixture that consists of materials extracted from wood pulping waste liquors, such as resins, fatty acids, sterols, and/or alcohols of high molecular weight.

Tall  Oil • The principal components of CTO include saturated and

unsaturated C18 FFA, resin acids and other non-acidic compounds.

• The global annual production of CTO is approx. 1.4 million tonnes, out of which about 750,000 tonnes is produced in the USA

• On a pulp basis, each ton of pulp affords 140-220 pounds black liquor soaps, 70-110 pounds crude tall oil, yielding 30-50 pounds of TOFA.

• The main uses of tall oil fatty acids are alkyd resins, soaps, cleaners, detergents, surfactants, lubricants and ore flotation reagents and that of tall oil rosin acids are paper sizes, printing inks and adhesives.

• Time of year or growing cycle of the tree.

• The particular species involved.

• Aging of the wood.

• The amount of heartwood.

• Pulping conditions.

• The efficiency of the system used to recover the tall oil.

Analysis range of American Crude Tall Oil

Acid no. 153 - 170 Saponification no. 167 - 178 Iodine no. 165 - 176

Rosin acids, % 35 - 50 Fatty acids, % 41 - 59 Unsaponifiables, % 6 - 9 Moisture, % 0.2 - 1.2

The oil is distilled into five components with different boiling points:

• Tall oil heads (which boils first)

• Tall oil fatty acids

• Distilled tall oil (a mixture of fatty and resin acids)

• Resin acids (collectively known as rosin)

• Pitch (the residue)

Renewable Diesel vs BiodieselThree defining characteristics Price Alternative, lower cost feedstocks Process Uses traditional refinery processes. Catalytic

cracking. Properties Chemically identical to petroleum diesel

Scope of Project Biodiesel from tall oil gives good yield percentage

from TOFA fraction.

Catalytic cracking may convert other fractions of CTO along with TOFA effectively

Effect of Crude Tall Oil on commercial catalyst

Equipment GC-MS with a catalyst bed

built in.

Custom configuration allows for cracking of a compound over catalyst in situ.

Can accept solid, gas, or liquid samples.

Mass input into MS is independent of flow over catalyst bed.

Transfer Line (200˚C)

He

ˉ40 – 350˚CRX-1MS Column

50 -

400

˚C

ˉ40

- 30

0˚C

Sample Injector Catalyst Bed

Split Flow

1 mL/min15 mL/min

14 mL/min

Purge gas forcolumn change

MS-OpenSplit System

He, H2

Catalyst: ZSM-5ZSM-5 is a crystalline silica/alumina catalyst widely used in laboratory experiments and elucidation of cracking characteristics.

Catalyst Characteristics

• SiO2 / Al2O3 = 23 (36)

• Surface Area = 450 m2 / g• Particle Diameter = 1 µm• Pore Size = 0.55 nm

Results: Crude Tall Oil

10 20 30 40minutes

0.0

2.5

5.0

7.5

MCounts

0

1

2

3

4

MCounts

cto s-a2 2-1-2011 4-44-53 PM CTO .SMS TIC50:650

cto s-zsm-5-400-a1 2-3-2011 11-17-40 AM CTO.SMS TIC50:650

Results: TOFA

5 10 15 20 25 30 35minutes

0.0

2.5

5.0

7.5

10.0

12.5

15.0

MCounts

0.0

2.5

5.0

7.5

10.0

MCounts

xtol 100 s-i2 1-31-2011 12-20-15 PM TOFA xtol .SMS TIC50:650

xtol s-zsm-5-400-a1 2-16-2011 5-33-41 PM TOFA xtol .SMS TIC50:650

TGA Analysis: CTO coke removal

0.01350mg (2.101%)

0.59

0.60

0.61

0.62

0.63

0.64

Weig

ht

(mg

)

100 200 300 400 500

Temperature (°C)

Sample: cto-5-400-coke removalSize: 0.6424 mgMethod: Ramp

TGA-DTAFile: C:...\cto 400\cto-5-400-coke removal.001

Run Date: 31-Mar-11 19:36

Universal V3.0G TA Instruments

2.101%

TGA Analysis: CTO activity test

0.04100mg cto-5-400-at(6.000%)

0.62

0.64

0.66

0.68

We

igh

t (m

g)

100 150 200 250 300 350 400 450

Temperature (°C)

Sample: cto-5-400-activity testSize: 0.6833 mgMethod: Ramp

TGA-DTAFile: C:...\cto-5-400-activity test.001

Run Date: 31-Mar-11 21:41

Universal V3.0G TA Instruments

6.000%

TGA analysis: TOFA coke removal

0.01280mg (1.489%)

0.76

0.78

0.80

0.82

0.84

We

igh

t (m

g)

100 200 300 400 500

Temperature (°C)

Sample: xtol-5-400-coke removalSize: 0.8596 mgMethod: Ramp

TGA-DTAFile: C:...\xtol-5-400-coke removal.001

Run Date: 4-Apr-11 16:27

Universal V3.0G TA Instruments

1.489%

TGA analysis: TOFA activity test

0.05356mg (6.515%)

0.72

0.74

0.76

0.78

0.80

0.82

Weig

ht

(mg)

50 100 150 200 250 300 350 400 450

Temperature (°C)

Sample: xtol-5-400-activity testSize: 0.8221 mgMethod: Ramp

TGA-DTAFile: C:...\xtol-5-400-activity test.001

Run Date: 4-Apr-11 18:36

Universal V3.0G TA Instruments

6.515%

Conclusions

Tall Oil Rosin Acids have effect on the catalyst.

Crude tall oil can be reacted along with the TOFA.

Results show that the crude tall oil can be cracked into fuel.

• Comparison of obtained biodiesel with that of biodiesel obtained from soybean oil.

• Comparison of obtained green diesel with the petroleum diesel.

Questions?