Atmospheric Hydrodeoxygenation of Biomass Fast Pyrolysis Vapor by

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Atmospheric hydrodeoxygenation of biomass fast pyrolysis vapor by MoO Guofeng Zhou, Peter Arendt Jensen, Duy Michael Le, Niels Ole Knudsen, and Anker Degn Jensen ACS Sustainable Chem. Eng., Just Accepted Manuscript • DOI: 10.1021/ acssuschemeng.6b00757 • Publication Date (Web): 15 Aug 2016 Downloaded from http://pubs.acs.org on August 22, 2016

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ACS Sustainable Chemistry & Engineering

Atmospheric hydrodeoxygenation of biomass fast pyrolysis vapor by MoO3 Guofeng Zhou,† Peter A. Jensen, † Duy M. Le, ‡ Niels O. Knudsen,‡ and Anker D. Jensen*† †

Department of Chemical & Biochemical Engineering, Technical University of Denmark,

Søltofts Plads Bygning 229, Kgs. Lyngby 2800, Denmark ‡

DONG Energy, Kraftsværksvej 53, DK-7000, Fredericia, Denmark

*E-mail: [email protected] KEYWORDS: Biomass, Fast Pyrolysis, Catalytic Upgrading, Hydrodeoxygenation, MoO3

ABSTRACT

MoO3 has been tested as a catalyst in hydrodeoxygenation (HDO) of both model compounds (acetone and guaiacol) and real biomass pyrolysis vapors under atmospheric pressure. The pyrolysis vapor was obtained by fast pyrolysis of wood or lignin in a continuous fast pyrolysis reactor at a fixed temperature of 500°C, and it subsequently passed through a downstream, close coupled, fixed bed reactor containing the MoO3 catalyst. The influences of the catalyst temperature and the concentration of H2 on the HDO of the pyrolysis vapors were investigated. The level of HDO of the biomass pyrolysis vapors was not significant at temperatures below 400°C. At 450°C catalyst temperature and 93 vol.% H2 concentration, the wood pyrolysis vapor

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was more active towards cracking forming gas species instead of performing the desired HDO forming hydrocarbons. The lignin pyrolysis vapor was more resistant to cracking and yielded 16.2 wt.%daf organic liquid, while achieving 52% degree of deoxygenation at 450°C catalyst temperature under 89 vol.% H2 concentration. The corresponding energy recovery in the liquid phase was 23.5%. The spent catalyst showed two deactivation routes, coke formation and reduction of MoO3 to MoO2, which is inactive in HDO. The catalyst experienced severe reduction at temperatures higher than 400°C. The yields of coke relative to the fed biomass were in the range of 3-4 wt.%daf for lignin and 5-6 wt.%daf for wood. Compared to untreated bio-oil the upgraded lignin organic liquid showed improved compatibility with hydrocarbons, and was miscible with a toluene/heptane mixture.

INTRODUCTION Fast pyrolysis technology has been developed for more than 30 years. By this process, biomass is heated to 450–600°C in the absence of oxygen, whereby it is converted into a liquid product, known as bio-oil, as well as a solid char product and gases. Bio-oil has a high oxygen content, which is typically similar to its biomass precursor. For example, the oxygen content of wood biooil is about 35–40 wt.%, compared to about 42 wt.% oxygen content of wood.1 The oxygen content of lignin bio-oil is about 25 wt.%, compared to 24 wt.% oxygen content of lignin.2,3 A subsequent upgrading step, typically including a catalyst, can be used to remove the oxygen and transform the bio-oil into molecules which are compatible with engine fuels. The two most common upgrading steps are high pressure HDO producing mainly saturated hydrocarbons and zeolite cracking producing benzene, toluene and xylenes (BTX).


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Catalysts which have been tested for high pressure HDO include noble/non-noble metals, transition metal sulfides, oxides, nitrides, carbides, and phosphides.4,5 Currently, two high pressure (catalytic) hydro-pyrolysis reactors with close coupled catalytic upgrading systems have been built.6-9 Marker et al.6 used a 0.45 kg/h scale bubbling fluidized bed for high pressure catalytic hydro-pyrolysis with a close coupled catalytic hydro-conversion reactor, known as the IH2 process. Different biomasses, such as corn stove, wood, etc., were converted successfully. For instance, using wood as a feedstock, 26.4 wt.% yield of C4+ hydrocarbons with less than 2.2 wt.% oxygen content of the total organic liquid was produced.6 Venkatakrishnan et al.7,8 designed a cyclone type high pressure hydro-pyrolysis reactor and a close coupled catalytic HDO reactor with the ability to feed 0.1–20 g/min biomass. They tried three different catalysts, including Ru/Al2O3, Pt/Al2O3, and PtMo supported by multi-walled carbon nanotubes (PtMo/MWCNT). PtMo/MWCNT was found to be a good HDO catalyst which produced 32% and 55% carbon yield of C4+ hydrocarbons from poplar wood and cellulose, respectively.7 While high pressure processes generally allow for a high level of deoxygenation, it is challenging to feed low density biomass into pressurized systems. Hydrodeoxygenation of bio-oil under atmospheric pressure has been shown possible using mainly bio-oil model compounds. Catalysts which have been tested for atmospheric HDO include supported metals, metal oxides, carbides, and phosphides.10-19 Among them, MoO3 has been tested using both model compounds and real biomass.17-19 Prasomsri et al.18 found that MoO3 was the most active catalyst for atmospheric HDO of acetone among several oxides, such as WO3, CuO, V2O5, and Fe2O3. They further showed that MoO3 was also active for HDO of ethers, anisole and phenolic compounds.17 Using m-cresol as a model compound, Prasomsri et al.17 found that the conversion decreased from above 80% to about 60% after 7 hours of


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operation at 350ᵒC catalyst temperature, but at higher temperatures, such as 400ᵒC, the conversion quickly decreased from about 100% to 10% after 4 hours operation due to the reduction of MoO3 to MoO2, which is inactive of HDO.17 Nolte et al.19 recently studied MoO3 HDO of cellulose, lignin, and corn stover pyrolysis vapors at 400°C and 1.8 bar H2 pressure in a batch-wise micro-pyrolyzer connected to a downstream fixed bed reactor containing the HDO catalyst. Total yields of 44-53%, 16-23%, and 15-26% C4+ hydrocarbons on carbon basis were reported from cellulose, lignin, and corn stover, respectively. Different from high pressure HDO, which produces saturated hydrocarbons, low pressure HDO produces mainly unsaturated hydrocarbons and aromatics, which are the thermodynamically stable species at low hydrogen pressure and high temperature. Thermodynamic analysis of guaiacol HDO showed that ring saturation was not favored at temperatures higher than 427ᵒC.10 Most of the catalysts that were proved as potential HDO catalysts under atmospheric pressure have not been tested all the way from model compounds to real biomass pyrolysis vapors, and hence only little knowledge has yet been gained about their ability to upgrade real bio-oil. In this work, we investigated such an upgrading technique using a bench scale continuous pyrolysis centrifuge reactor to pyrolyze the biomass and a close coupled catalytic reactor for MoO3 HDO of the biomass pyrolysis vapors. Because fast pyrolysis and catalytic upgrading take place in separate units, it is possible to keep the fast pyrolysis step at the optimal condition and investigate the effect of the HDO conditions individually. Due to the success of the MoO3 catalyzed HDO of both bio-oil model compounds and real biomasses in micro scale pyrolysis apparatuses,17-19 it was chosen as a catalyst for this study. Different feedstocks including bio-oil model compounds, lignin, and wood were tested.


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EXPERIMENTAL SECTION Materials. The lignin was obtained as a solid residue in the form of dried pellets from a wheat straw based second-generation bio-ethanol pilot plant, Inbicon A/S, situated in Kalundborg, Denmark. The lignin pellets were crushed in a cutting mill and were sieved to a particle size of 0.35 to 1.4 mm. The beech wood was the same wood studied by Trinh et al.2 The particle size of the beech wood was less than 1 mm. The catalyst, MoO3 (≥ 99.5%), used in this work was purchased from Sigma-Aldrich. The MoO3 powder was mixed with about 10% demineralized water and the moist powder was pressed into tablets using a laboratory tablet press. The tablets were calcined in an oven at 500°C for 5 hours in air. The catalyst tablets were then crushed and sieved to obtain a particle size of 500–850 µm. For a typical run, 40 g fresh pretreated catalyst was mixed with 60 g sand (350–450 µm). Acetone (≥ 99.8%) was purchased from SigmaAldrich. Guaiacol (≥ 98%) was purchased from SAFC. Experimental Procedure. A sketch of the experimental setup is shown in Figure 1. The biomass particles were fed tangentially to the horizontally oriented pyrolysis reactor cylinder where the centrally mounted rotor with arch-shaped blades pushed the particles against the electrically heated reactor wall. The reactor was kept at 500°C. While circulating on the wall, the particles simultaneously moved axially towards the tangential reactor outlet. After the reactor, the flow of gas and particles were first directed to a change-in-flow-direction separator (460°C), a cyclone (440°C), and then a hot gas filter (300°C) to remove solid char. The hot gas filter is made of stainless steel with 6 cm outer diameter and 24.5 cm length, and the pore size is 1 µm. The filter housing is 26.5 cm long and 9 cm inner diameter. The char free gas then passed


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through a fixed bed catalytic reactor. The catalytic reactor is made of stainless steel and is 20 cm long and 2.1 cm inner diameter. A series of condensers was used to collect the liquid. There were four condensers, made of stainless steel, inside a cooling bath kept at −20ᵒC. The first condenser is 25 cm long and 7 cm inner diameter. The remaining three condensers are 15.5 cm long and 4.8 cm inner diameter. There were another four glass cold traps inside the ethanol/dry ice bath at −70ᵒC. The cold traps are 20 cm long and 2 cm outer diameter. About 100 g isopropanol in total was added to the first three condensers to help the condensation. A carrier gas of 4, 6, 8 Nl/min H2 (catalytic runs) or 4 Nl/min N2 (non-catalytic runs), preheated to 450°C, was introduced to the reactor. Depending on the flowrate of the carrier gas (4, 6, or 8 Nl/min), the gas residence time of the pyrolysis reactor was 0.9, 1.4, or 1.8 seconds. The gas residence time of the hot gas filter was 6, 9, or 12 seconds. The gas residence time of the separator and cyclone were small, < 0.1 second. A typical experiment lasted 25 minutes. The screw feeder was kept at 10 rpm, which gave 1.7–2.1 g/min feeding rate of lignin and 0.7–0.8 g/min feeding rate of wood. The model compounds were fed into the gas stream after the gas preheater by a HPLC pump. The MoO3 was not subjected to a pre-reduction, except for the experiments carried out at 350°C catalyst temperature. In this case the catalyst was pre-reduced at 320°C in a flow of H2 for three hours prior to the experiment in order to avoid the induction phase of the HDO reaction.17 The total liquid product was determined by the weight difference of the condensers before and after the experiment. The char yield was determined by the weight difference of the two char bottles, plus the collected char from the hot gas filter. For the gas samples, 0.2 Nl/min of product gas was continuously pumped to a gas sample bag during the experiment, and the remaining gas was sent to the ventilation. The catalytic coke was determined by temperature programmed oxidation (TPO). For the TPO, the spent MoO3 (500–850 µm) and the sand (350–450 µm) were first


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separated by size. Then 2 g of MoO3 and 3 g of sand were heated up together in an oven to 650°C with 10 °C/min heating rate under 3 Nl/min carrier gas containing 10% O2 in N2. The CO and CO2 generated from the TPO were monitored by a continuous gas analyzer (Rosemount NGA2000) and the total carbon deposition was calculated by counting all the carbons in the carbon oxides. The amount of water produced due to MoO3 reduction was calculated by the weight difference before and after the TPO plus the weight of carbon deposition. All the yields are reported as weight percentage on dry ash free biomass basis (wt.%daf). To calculate the product yields on dry ash free biomass basis, the ash was assumed to be only present in the char.2 Throughout the paper, bio-oil refers to a mixture of reaction water and organic liquid, while the water free bio-oil is referred to as the organic liquid.

Figure 1: Sketch of the Pyrolysis Centrifuge Reactor setup Characterization of Biomass. The sugar and lignin contents of the feedstock were analyzed following the NREL protocols.20 The moisture content was determined following ASTM D444215 and the ash content was determined following ASTM D1102-84. The mineral compositions


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were determined by X-ray fluorescence spectrometry (Ramcon Supermini 200). A long continuous scan was performed to identify the elements heavier than Sc. Separate scans were performed to detect lighter elements (Na to Sc). The detected elements were automatically annotated. The net intensities were calculated by subtracting the background intensity. The mineral compositions were calculated from the net intensities. The organic C, H, and N, contents were measured by a EuroVector EA Elemental Analyzer and used to account for inter-element interference. The properties of feedstocks are summarized in Table 1. It can be seen that lignin contains 21.4 wt.%db of sugar residues and a rather high ash content of 12.0 wt.%db. In bioethanol production, it is the sugars that are dissolved, and not lignin, opposite to paper based processes. Furthermore, NaOH, Ca(OH)2, or KOH was used in bio-ethanol production to adjust the pH, and hence the lignin used in this study has a high content of, especially Na and K. Table 1: Lignin and wood properties Parameter

Lignin

Wood a

Moisture, wt.%

4.5

7.0

Ash, wt.%db

12.0

2.7

Klason lignin, wt.%db

56.3

23.8

Glucan, wt.%db

14.7

39.0

Xylan, wt.%db

6.1

17.1

Arabinans, wt.%db

0.6

1.0


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Galactan, wt.%db

-

1.6

Mannan, wt.% db

-

1.6

Others, wt.%db b

10.3

12.2

C

51.3

51.3

H

6.1

5.7

N

1.4

0.21

Oc

29.2

40.5

Na

0.61

0.02

Mg

0.04

0.04

Al

0.04

0.05

Si

4.60

0.84

P

0.04

0.01

S

0.12

0.03

Cl

0.12

500°C). The three peaks correspond to carbide, oxycarbide/soft coke, and graphitic coke.17 The main carbonaceous material on the spent catalyst was a combination of oxycarbidic carbon and soft coke. The XRD analyses of the spent catalysts are summarized in Figure 5. The spent catalysts used for the XRD analysis were chosen from the bottom of the catalyst bed, where the deactivation should be least severe. The spent catalysts used at temperatures higher than 400°C were completely reduced to MoO2 during the 25 minutes experiments. This means that the liquid product collected from the optimal catalyst temperature, 450oC, was possibly only being partially upgraded due to the quick reduction of MoO3. Such a quick reduction also means that a practical implementation of a catalytic process using MoO3 would need to involve frequent (minute scale or continuous) regeneration of the catalyst by oxidation. It may be possible that operating at a high temperature and a low H2 pressure would allow a significant rate of the HDO reaction while avoiding the quick reduction of MoO3 to MoO2. Such an optimization of the operating conditions would be part of future work.


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Spent catalyst @ 550°C

Spent catalyst @ 500°C Intensity

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Spent catalyst @ 350°C 100

200

300 400 Temperature, °C

500

600

Figure 4: CO2 profiles from TPO analyses of the spent MoO3 catalysts used for upgrading lignin pyrolysis vapor at different catalyst temperatures with 4 Nl/min H2 flow rate.


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Figure 5: XRD analyses of the spent MoO3 catalysts used for upgrading lignin pyrolysis vapor at different catalyst temperatures with 4 Nl/min H2 flow rate. The symbol (+) and the dash line indicate the peak assignment corresponding to MoO2 DISCUSSION The conversions of model compounds over MoO3 presented in the literature were higher than 50% at 350°C catalyst temperature and the selectivity towards hydrocarbons was almost 100%.17,18 Our study also confirmed the effectiveness of MoO3 HDO of bio-oil model compounds. However, moving from bio-oil model compounds to real biomass pyrolysis vapors, less encouraging results were obtained. Wood pyrolysis vapor suffered a high degree of cracking reactions forming mainly gas species under the investigated conditions, while lignin pyrolysis vapor achieved 16.2 wt% organic liquid yield and 52% degree of deoxygenation at 450°C and 89 vol.% H2 concentration.


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To gain a better understanding of why MoO3 HDO of biomass pyrolysis vapor was less efficient than model compounds, an experiment was conducted using MoO3 upgrading of lignin pyrolysis vapor at 400°C, where the deactivation is slow, with additionally 0.15 g/min acetone being cofed. Four gas bags were collected at time 4-6, 12-14, 17-19, and 23-25 minutes during the experiment to measure the conversion of acetone to propene and propane, which are the main HDO products from acetone. The results are shown in Figure 6. It takes about 5 minutes for the lignin particles to reach the pyrolysis reactor from the screw feeder in our setup, and hence the first collected gas bag shows high conversion of acetone to propene and propane. After the lignin pyrolysis vapor reached the catalyst bed, the conversion of acetone to propene and propane decreased significantly. It is unlikely that the MoO3 was deactivated soon after the lignin pyrolysis vapor reached the MoO3 catalyst at 400°C. The spent MoO3 used at 400°C catalyst temperature for upgrading the lignin vapor was tested again for the HDO of model compounds, and it was still able to perform HDO of acetone and guaiacol, as shown in the supporting information Table S4. The results therefore indicate that the HDO activity of MoO3 was inhibited by the presence of lignin pyrolysis vapor. Water is one of the known reasons to inhibit the HDO reactions over MoO3, which was observed in the current as well as other studies.18 Additionally, we speculate that the lignin fragments, which are significantly larger than the model compounds, poisoned the catalyst sites due to strong adsorption. For instance, using the petroleomic method, Olcese et al.24,25 found that the heavy species with more than 5 oxygen atoms derived from fast pyrolysis of lignin were completely trapped or converted by the Fe/SiO2 catalyst at atmospheric pressure and 400oC catalyst temperature. They suspected that those species were most probably condensed and converted into the coke deposit. Nolte et al.19 studied MoO3 upgrading of biomass pyrolysis vapors at 1.8 bar H2 pressure using a micropyrolyzer and


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obtained 16-23% carbon yield of C4+ hydrocarbons from lignin. They used an excess amount of MoO3 (200 mg) to upgrade a small amount of lignin 200-300 µg. Hence neither water inhibition nor poisoning of the sites by the lignin fragments may have played a significant role in their study. It was found by Shetty et al.26 that the reaction rate was zero order for the oxygenate concentration (m-cresol) during HDO by supported MoO3 catalysts under the investigated condition. Further increasing the catalyst to biomass feed ratio might help to achieve a better deoxygenation of lignin pyrolysis vapor and it should be considered as future improvement. Industrially this is however, unlikely to be attractive since the productivity of the process would be low.

90 Acetone conversion to products, % on carbon basis

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80

Propene

Propane

Total conversion

70 60

Co-feed acetone together with lignin

50 40 30 20 10 0 4-6 min

12-14 min

17-19 min

23-25 min

Feed 1 model compounds study

Figure 6: Acetone conversion to propene and propane at different times during fast pyrolysis of lignin combined with MoO3 HDO. Pyrolysis conditions: 2 g/min feeding rate of lignin and 0.15 g/min feeding rate of acetone; 1.8 seconds pyrolysis reactor gas residence time (4Nl/min H2); 500oC pyrolysis reactor temperature; 300oC filter temperature. Catalytic upgrading conditions:


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40 g fresh MoO3 with 60 g; 400oC catalyst temperature. The figure also presents the acetone conversion to propene and propane obtained from feed 1 model compounds study. The compatibility of untreated lignin heavy organic liquid and the upgraded heavy organic liquid with a toluene/heptane mixture (1:1 on weight basis) was tested. The test was conducted by adding toluene/heptane mixture into the heavy organic liquid. The upgraded heavy organic liquid was miscible with the toluene/heptane mixture, but this was not the case for the untreated heavy organic liquid. It indicates that the upgraded lignin organic liquid shows better compatibility with hydrocarbons in agreement with its lower oxygen content. CONCLUSION Acetone and guaiacol were used as model compounds of bio-oil to study MoO3 HDO at 400oC under atmospheric pressure. In agreement with literature findings, MoO3 was found to selectively cleave C-O/C=O bonds and produce the corresponding unsaturated hydrocarbons. To test the applicability of MoO3 as a catalyst for HDO of real biomass pyrolysis vapor, lignin and wood were pyrolyzed in a continuous pyrolysis reactor and the vapors were subsequently upgraded over a downstream, close coupled, fixed bed reactor containing the MoO3 catalyst. Temperatures higher than 400°C were needed to obtain a decent degree of deoxygenation. However, a high temperature, such as 450°C, promoted cracking reactions for the wood pyrolysis vapor. Only 4.6 wt.%daf organic liquid product, mainly hydrocarbons, was produced from wood at 450°C catalyst temperature. The lignin pyrolysis vapor was more resistant to cracking. At 450oC catalyst temperature and 89 vol.% H2 concentration, the yield of organic liquid was 16.2 wt.%daf with 11.5 wt.% oxygen content and the energy recovery was 23.5%. The reasons for the lignin pyrolysis vapors being harder to upgrade than simpler model compounds


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such as guaiacol are likely due to water inhibition, strong adsorption to the active sites of the larger pyrolysis vapor molecules, and steric hindrance effects. When operating the catalyst at high temperatures (≥ 450℃), a severe reduction of MoO3 to MoO2 was observed by XRD analysis of the spent catalysts. There is thus a tradeoff between obtaining sufficient catalyst activity and deactivation at the optimum temperature. A practical implementation of a catalytic process using MoO3 as a catalyst for HDO of biomass pyrolysis vapors would thus likely need to involve frequent (minute scale or continuous) regeneration of the catalyst by oxidation. The improved compatibility of the final product with hydrocarbons however, is expected to make the product easier to be integrated into refinery streams for further upgrading. ASSOCIATED CONTENT Supporting Information. Detail chemical compounds of the light organic liquid, effect of H2 concentration on MoO3 HDO of lignin pyrolysis vapor, and a model compounds study using a spent MoO3 are shown in the supporting information. This material is available free of charge via the Internet at http://pubs.acs.org. AUTHOR INFORMATION Corresponding Author *E-mail: [email protected] ACKNOWLEDGMENT The present work is funded by Technical University of Denmark, DONG Energy and the Danish National Advanced Technology Foundation (project Biomass for the 21st Century, no. 001-


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2011-4). The authors are very grateful to Kenny Ståhl from Technical University of Denmark and Asger B. Hansen from Haldor Topsøe, who have helped with the XRD and GC×GC analyses, respectively. REFERENCES

1. Bridgwater, A. V. Review of fast pyrolysis of biomass and product upgrading. Biomass Bioenergy 2012, 38, 68-94. 2. Trinh, T. N.; Jensen, P. A.; Dam-Johansen, K.; Knudsen, N. O.; Sørensen, H. R.; Hvilsted, S. Comparison of lignin, macroalgae, wood, and straw fast pyrolysis. Energy Fuels 2013, 27, 1399-1409. 3. Trinh, T. N.; Jensen, P. A.; Sárossy, Z.; Dam-Johansen, K.; Knudsen, N. O.; Sørensen, H. R.; Egsgaard, H. Fast pyrolysis of lignin using a pyrolysis centrifuge reactor. Energy Fuels 2013, 27, 3802-3810. 4. Saidi, M.; Samimi, F.; Karimipourfard, D.; Nimmanwudipong, T.; Gates, B. C.; Rahimpour, M. R. Upgrading of lignin-derived bio-oils by catalytic hydrodeoxygenation. Energy & Environmental Science 2014, 7, 103-129. 5. Ruddy, D. A.; Schaidle, J. A.; Ferrell III, J. R.; Wang, J.; Moens, L.; Hensley, J. E. Recent advances in heterogeneous catalysts for bio-oil upgrading via “ex situ catalytic fast pyrolysis”: catalyst development through the study of model compounds. Green Chem. 2014, 16, 454-490. 6. Marker, T. L.; Felix, L. G.; Linck, M. B.; Roberts, M. J. Integrated hydropyrolysis and hydroconversion (IH2) for the direct production of gasoline and diesel fuels or blending components from biomass, part 1: Proof of principle testing. Environmental Progress & Sustainable Energy 2012, 31, 191-199. 7. Venkatakrishnan, V. K.; Delgass, W. N.; Ribeiro, F. H.; Agrawal, R. Oxygen removal from intact biomass to produce liquid fuel range hydrocarbons via fast-hydropyrolysis and vaporphase catalytic hydrodeoxygenation. Green Chem. 2015, 17, 178-183. 8. Venkatakrishnan, V. K.; Degenstein, J. C.; Smeltz, A. D.; Delgass, W. N.; Agrawal, R.; Ribeiro, F. H. High-pressure fast-pyrolysis, fast-hydropyrolysis and catalytic hydrodeoxygenation of cellulose: production of liquid fuel from biomass. Green Chem. 2014, 16, 792-802. 9. Marker, T. L.; Felix, L. G.; Linck, M. B.; Roberts, M. J.; Ortiz‐Toral, P.; Wangerow, J. Integrated hydropyrolysis and hydroconversion (IH2®) for the direct production of gasoline


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Title: Atmospheric hydrodeoxygenation of biomass fast pyrolysis vapor by MoO3 Authors: Guofeng Zhou, Peter A. Jensen, Duy M. Le, Niels O. Knudsen, and Anker D. Jensen Table of Contents Graphic:

Biomass

Pyrolysis Centrifuge Reactor

Renewable fuels

Pyrolysis vapor Char

Fast pyrolysis

MoO3 HDO

Synopsis: Continuous fast pyrolysis of biomass and direct hydrodeoxygenation of pyrolysis vapor by MoO3 under atmospheric pressure produces partly deoxygenated organic liquid.


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Atmospheric Hydrodeoxygenation of Biomass Fast Pyrolysis Vapor by

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