Wei Mu, Prof. Yulin Deng

Institute of Paper Science and Technology

Georgia Institute of Technology

Catalytic hydrodeoxygenation of

pyrolysis oil derived from lignin

Date: Mar 12, 2014

Reference: [1] U.S. Energy Information Administration / Annual Energy Review 2009

[2] http://www.saabhistory.com/2007/06/

Definition: Energy which comes from natural resources such as sunlight, wind, rain, tides,

and geothermal heat, which are renewable (naturally replenished)

Renewable Energy & Biomass

1

Functions of lignin

• Conducting water in plant stems.

• Providing mechanical support and structure.

• Resisting attack by most microorganisms.

Lignins, by John Ralph, Gosta Brunow, Wout Boerjan, ENCYCLOPEDIA OF LIFE SCIENCES & 2007, John Wiley & Sons, Ltd. www.els.net 3

Chemical structure of lignin

Oxygen/Carbon ratio (mole)

0 1.00.5

Hydrogen/Carbon ratio (mole)

0 2.01.0

Structure and elemental composition of lignin

2

Compare with gasoline and diesel. is lignin and is carbohydrate.

Carbon Chain Length

5 2010 15

Lignin monomer here. Typically organosolv lignin has about 150 carbons/molecule.

Barth and Kleinert. 2008. Energy Fuels. 22:1371-1379.

Lignin

Degradation

Crude Oil

4

Approach

Overview of My Research

LigninDegradation to small fragments

Upgrading

Biofuel

Objective: Convert lignin, which is a waste biomass, into biofuel or biochemical.

5

• Approach: Thermochemical treatment followed by hydrodeoxygenation upgrading.

• Catalyst screen: use model compound for reaction mechanism study

• Challenge: product analysis. Lignin has very complex structure.

PyrolysisN2 flow

400-600 oC

Biomass

Pyrolysis:

- Thermochemical conversion

process

- Break down the biomass in

the absence of oxygen.Furnace

N2 flow

Condenser

Liquid N2

Quartz tube Sample boat

Heavy oil Light oil Solid

+ + +

Gas products

• CO and CO2 ( >50%)

• H2 (~25 mol%)1

• Aliphatics, HCHO,

CH3CHO, etc

Pyrolysis oil: Dark brown liquids which

are comprised of hundreds of highly

oxygenated organic compounds2

Mainly recognized as

char with high energy.

Pyrolysis of Lignin

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Gasoline Gasoil/diesel Carbohydrate Lignin

Carbon chain length 5-10 12-20 [6-5]n [9-10]n

0 5 10 15 20 25 30 35

Number of carbons

Heavy Oil

Light Oil

Gasoline

Heavy oil: Molecule weight between 200 – 1200 Dalton.

Chemical Review 2010, 110

Composition of Pyrolysis Oil

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Heavy oil

Catalytic Hydrogeoxygenation

Hydrogen gas

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Advantage Disadvantage

CoMoS2 Low cost, not poisoned by sulfur

Low reactivity, poisoned by water

Noble Metal Very active, water resistance

High price, poisoned by sulfur

• Unlike petroleum oil, biomass oil is inherently low sulfur and contains water.

• Noble metal catalysts can be run under low temperature, leads to less coke.

Pressurized reactor

Catalyst Screening

Light oil

• Mainly water soluble monomers.

• Ignored by many researchers because of large amount of water in light oil (~40-80w/w%)

• Yield of light oil from pyrolysis is around 15-35%.

• Overall weight of organic compounds in light oil is still over 1/3 the weight of heavy oil.

Upgrading of Light Oil

Light oil

•Result• High carbon yield. Approximately 100%.

• Fully hydrogenated. No aromatic ring left in the products.

• Cyclohexanol is the main product from the light oil upgrading.

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Upgrading of Heavy Oil

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Hydrodeoxygenation

H2 pressure, withNoble metal Catalyst

Gasoline-range productsHeavy oil

Dimer to trimer

• 2-step HDO reaction is required due to the tar formation deactivated the catalyst.

Fresh Step 1 Step 2

• Tentative reaction path

• First report about complete upgrading lignin pyrolysis oil to total aliphatic components by hydrogenation

Upgrading of Heavy Oil

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• Products in pyrolysis oil from lignin were analyzed.

• Catalytic reaction

• Reaction mechanism of different noble metal catalyst was proposed from model compounds study.

• Both major components from pyrolysis oil were upgraded into gasoline range. Light oil upgrading only needed one step HDO. Heavy oil upgrading required two step HDO due to the tar forming.

• Monomers were produced through pyrolysis and HDO upgrading. (GPC) Fully hydrogenation and intensively deoxygenated products was obtained. (NMR)

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Conclusion

• Prof. Yulin Deng

• The whole Deng’s Group

• Institute of Paper Science and

Technology

• School of Chemical and

Biochemical Engineering

Acknowledgement

Q & A