|Date 25.06.20101

Upgrading of Pyrolysis Oilwith Catalytic Hydrotreatment

Agnes ArdiyantiErik Heeres

|Date 25.06.2010

Lignocellulosic biomass(“woody biomass”)› Source: wood, grass, sawmill dust› Composition (in wt-%)1:

› Potential: 13 EJ (minimum) in 2030

2

softwoods hardwoods grassescellulose 40-44 43-47 40hemicellulose 25-29 25-35 35lignin 25-31 16-24 12extractives 1-5 2-8 13

1WUR; 2van Dam, 2007

|Date 25.06.20103

Lignocellulosic biomass – valorisation pathways

|Date 25.06.2010 28-10-09 | 4

Fast Pyrolysis Oil

Lignocellulosic biomass

Fast PyrolysisCondensables, Fast Pyrolysis Oil

Char

Volatiles

450-600 oC, 1-2 s

BTG, EnschedeBridgewater et al, Org. Geochem, 30,1999

|Date 25.06.2010

Fast pyrolysis oil5

› High oxygen content (up to 50%)

› Immiscible with petroleum products

› Unstable upon heating and storage (coke formation, repolymerization)Pyrolysis oil composition

C (wt%) 40.1

H (wt%) 7.6

O (wt%) 52.1

Moisture (wt%) 23.9

|Date 25.06.2010 28-10-09 | 6

Objective:Deoxygenation of Pyrolysis Oil

Fast pyrolysis oil DeoxygenationCo-feedstock for refineries (FCC, hydrocracking)

Catalyst, P, T

Fast pyrolysis oil

H2

Upgraded Oil

Gas

Water

Selected process: Catalytic Hydrotreatment

-(CHxOy)- + c H2 -(CHx)- + (H2O, CO2, CH4, CO)

|Date 25.06.2010

Desired product› Low oxygen content› Low viscosity› Low molecular weight› High aliphatic content› Low coking tendency

7

|Date 25.06.2010 28-10-09

Catalytic hydrotreatment

Oxygen contentH/C, O/C ratioViscosityMolecular weightCoking tendency

CatalystHeating routeReactor design

Upgraded oil properties: Process variables:

|Date 25.06.2010

Heating route

9

|Date 25.06.2010

Why heating route?› Polymerization is very common! sticky,

gooey paste is produced, instead of a nice and liquid oil

› Pyrolysis oil contains 30 wt% sugar when heated: charring

10

Which condition should we apply to suppress this reaction?

|Date 25.06.2010 28-10-09 | 11

Pyrolysis Oil

› Thermal cracking releases O mainly as H2O and CO2

› Repolymerisation occurrs

› O is released as H2O, H2 is consumed

› Further consumption of H2 saturates the C-C double bonds and cracks the large molecules (similar to coal liquefaction)

HPTT HDO

Low H/C, High Mw

High H/C, Low Mw

175-225oC>250oC, H2, catalyst

>250oC, H2, catalyst

Hypothesis1,2

1 Gagnon, Ind. Eng. Chem. Res 27, 19882 Venderbosch, et al, J. Chem. Tech & Biotech, 85, 2009

|Date 25.06.2010 | 12

Experimental set-up

› 4 fixed-bed reactors in-series

› Feed: forest residue pyrolysis oil (VTT, Finland)

› Catalyst: Ru (5%)/C› H2 pressure: 200 bar› Variables: T, WHSV› Analysis:

Elemental composition, TGA, GPC, viscosity

1

2 3

4Feed vessel

PI

TIC

TIC

TIC

TIC

PI

cooler

Product vessel

KO vessel

PI

Vent

FI

QI

Heater 1 Heater2

Heater 3 Heater 4

MI

MI

Gas inlet

MFC

BTG, The Netherlands

|Date 25.06.2010 28-10-09

Effect of process conditions, visual observations

› High T in all 4 reactors Phase separation, clogging after 25 min

› Low T in all 4 reactors (‘Stabilization’) Phase separation at 225 oC or higher

› Low T in first reactors, high T at the end (‘Mild Hyd’) Phase separation, run for 3 days without clogging

› ‘2-stage Hyd’ (Hydrotreatment on ‘Mild Hyd’ organic product) Top organic layer formed, no clogging observed

Py-oil Mild Hyd 2-stage Hyd

|Date 25.06.2010 28-10-09

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6

0.1

0.2

0.3

0.4

0.5

0.6

ato

mic

O/C

atomic H/C

Van Krevelen plot

Py-oil (dry)

Stabilization 175 oC

Stabilization 225 oC

Hydrogenation dehydration hydrogenation

Mild hydrotreatment 2-stage

|Date 25.06.2010

Why H/C and O/C?

15

HDO

HDO

Coke formationH/C = 0.5O/C = 0

H/C = 1O/C = 1/6

H/C = 1O/C = 0

H/C = 1.7O/C = 0

|Date 25.06.2010 28-10-09 | 16

0

200

400

600

800

1000

1200

10203040oxygen content (wt%)severity of process

Mw

(g

/mo

l)

0

5

10

15

20

25

30

resi

du

e (w

t%)

(1) (2) (3)

Physical properties during further hydrotreatment

stab Mild 2-stage

Mw and TGA

Correlation between Mw and residue weight (TGA)

Py-oil

Mw

residue (TGA)

|Date 25.06.2010

TG residue, as a function of H/C and O/C

TGA residual weight [%] = 81.523 – 57.164 H/C + 32.25 O/C

17

Design-Expert® Sof tware

residue21.5869

2.8166

X1 = B: O/CX2 = A: H/C

0.11

0.22

0.34

0.45

0.56

1.24

1.30

1.36

1.42

1.48

0

7.25

14.5

21.75

29

re

sid

ue

B: O/C A: H/C

Estimation of physical properties is possible

|Date 25.06.2010

Change of composition: solvent fractionation

› Sugar, HMM decreases after reaction, leaving the apolar, low molecular weight components behind!

18

|Date 25.06.2010

1H-NMR (organic phase)

› Groups: aldehydes, aromatics, carbohydrates, methoxy, aliphatics

19

Pyrolysis oil

Stabilization 175 oC

Mild hydrotreatment

2nd hydrotreatment

|Date 25.06.2010

Upgraded oil as co-feeding

› Comparable yields are found for the petroleum feed (Long Residue) and mixture of Long residue+upgraded oil

de Miguel Mercader, App. Cat. B 96, 2010

In catalytic cracking

|Date 25.06.2010

Summary on heating route› Van Krevelen plot indicates the occurence of three

subsequent processes: hydrogenation, dehydration, hydrogenation

› During hydrotreatment, the Mw, viscosity, and TGA residue-weight of product oil increase during the stabilization step, then decrease at more severe conditions.

› High H/C and low O/C of the organic product is desired› The change of composition can be followed by e.g. solvent

fractionation and 1H-NMR.› Upgraded oil can be used as co-feeding in refinery units

21

|Date 25.06.2010

Catalyst

22

|Date 25.06.2010

What type of catalyst?› No specific reaction homogeneous is not an

option› Heterogeneous catalyst: Which support, active

metal, preparation?

23

|Date 25.06.2010

Support› Regenerable› Stable in water, acid, high temperature:

ZrO2, SiO2 potential

› High specific surface area (less important)

24

Active metal› Any metal with hydrogenation activity› Interesting: noble metals (Ru, Pd, Rh), Ni

(usually promoted)

|Date 25.06.2010

Noble metal vs cheaper transition metal

› Noble metal: high activity, easy maintenance, very high price

› “cheaper” transition metal: lower activity, prone to deactivation, cheap

25

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

1998 2000 2002 2004 2006 2008 2010

year

US

$/tr

oy

ou

nce

Ru

Rh

Pd

Ni

www.kitco.com

|Date 25.06.2010

Van Krevelen: comparison of activity

26

Pine oil

PdPt/ZrO2Pt/ZrO2

NiCu/C

NiCu/CeO2-ZrO2

cracking (NiCu/d-Al2O3)

crack+NiCu/CeO2-ZrO2

NiCu/CeO2

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7

ato

mic

O/C

atomic H/C

Pine oilRu/ C 5wt%Ru/ C 3.33wt%Ru/ C 2wt%+actPd/ CPdPt/ SiO2-Al2O3 (Albe)Rh/ CeO2Rh/ ZrO2 Rh/ CoSiO3Rh/ ZrO2 RhPd/ ZrO2RhPt/ ZrO2 Pd/ ZrO2PdPt/ ZrO2Pt/ ZrO2NiCu/ Al2O3FeCu/ Al2O3NiCu/ ZrO2NiCu/ CeO2(co)NiCu/ CeO2(wet)NiCu/ CNiCu/ CeO2-ZrO2cracking (NiCu/ d-Al2O3)crack+NiCu/ CeO2-ZrO2NiCu/ sibuniteNiCu/ CeO2

Noble metal cat (TKK/BIC), not flowable NiCu, Albe3, flowable

commercial noble metal catalyts, very low viscosity

Ru/C Pd/C

|Date 25.06.2010

Potential catalyst: NiCu› δ-Al2O3 as support (better stability than γ-Al2O3)

› Various Ni/Cu ratio

27

Catalystc Ni (wt%)

Cu (wt%)

ABET

(m2/g)

24.5Cu 24.5 - 123

5.92Ni18.2Cu 5.92 18.2 118

13.3Ni11.8Cu 13.3 11.8 86

13.8Ni6.83Cu 13.8 6.83 122

16Ni2Cu 16 2 92

20.8Ni 20.8 - 118

|Date 25.06.201028

Hydrogenation activities› Van Krevelen plot is used to calculate the hydrogenation

activities, blank experiment as the reference

16Ni2Cu

PO

20.8Ni13.8Ni 6.83Cu

13.3Ni 11.8Cu

5.92Ni 16.82Cu24.5Cublank

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6

atomic H/C (dry)

atom

ic O

/C (d

ry)

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

20.8Ni 16Ni2Cu 13.8Ni6.83Cu

13.3Ni11.8Cu

5.92Ni16.82Cu

24.5Cu

catalyst

hydr

ogen

atio

n ac

tivity

(g-1

)

16Ni2Cu and 13.8Ni6.83Cu are the most active

|Date 25.06.2010

Why is Cu needed?› Ni is a catalyst for CNT (carbon nanotube)

formation produces “carbon whiskers”, decrease the activity

› CNT formation is structure sensitive needs adjacent active sites

› Cu makes NixCu1-x alloy, and reduce the crystallite size the carbon formation is reduced

› Cu also helps the reduction

29

|Date 25.06.201030

XRD analysis

13.8Ni6.83Cu

20.8Ni

NiO

Ni

• No Ni(0) was found at 20.8Ni after reduction at 300 oC (reduction temperature of Ni is > 500 oC)

•Ni(0) was formed on 13.8Ni6.83Cu after reduction

Cu does not have HDO activity, but supports the reduction of Ni

Reduction was performed at 300 oC and 10 bar of H2

|Date 25.06.201031

What about the stability?HRTEM

Active metal particle size: 10 nm (fresh) 100 nm (spent).ICP showed leaching of Ni, Cu, and Al

Fresh 16.8Ni6.83Cu Spent 16.8Ni6.83Cu

Dissolution and recrystallisation of NiCu seem to occur

|Date 25.06.2010

Next? Find other supports …› Carbon, ZrO2, TiO2, etc

› Ongoing research

0.0 0.5 1.0 1.5 2.00

50

100

150

200

NiCu/ rice husk

NiCu/ ZrO2

NiCu/ CeO2-ZrO

2

NiCu/ TiO2

NiCu/ sibunite

non-catalytic

H2 c

onsu

mpt

ion

(NL/

kg f

eed)

Activity based on van Krevelen plot (g active metal -1)

|Date 25.06.2010

Summary on catalyst selection› A good support selection is a good start› Noble metal vs “cheaper” transition metal› Bimetallic catalyst: effect of composition

33

Heterogeneous catalysts, SϋdChemie

|Date 25.06.201034

Acknowledgement:Robbie Venderbosch, Vadim Yakovlev, Sofia Khromova, Jelle Wildschut, Anja Oasmaa, Jelmer Westra

UICUIC

Boreskov Institute of Catalysis – SB RAS