Green aromatic bulk-chemicals from lignin pyrolysis vapours

Transcription

1 Engineering Conferences International ECI Digital Archives BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals Proceedings Spring Green aromatic bulk-chemicals from lignin pyrolysis vapours B. Shrestha CNRS R. lcese CNRS J. Francois CNRS M. Bettahar CNRS D. Petitjean CNRS See next page for additional authors Follow this and additional works at: Part of the Chemical Engineering Commons Recommended Citation B. Shrestha, R. lcese, J. Francois, M. Bettahar, D. Petitjean, and A. Dufour, "Green aromatic bulk-chemicals from lignin pyrolysis vapours" in "BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals", Manuel Garcia- Perez,Washington State University, USA Dietrich Meier, Thünen Institute of Wood Research, Germany Raffaella cone, Heriot-Watt University, United Kingdom Paul de Wild, Biomass & Energy Efficiency, ECN, The Netherlands Eds, ECI Symposium Series, (2013). This Conference Proceeding is brought to you for free and open access by the Proceedings at ECI Digital Archives. It has been accepted for inclusion in BioEnergy IV: Innovations in Biomass Conversion for Heat, Power, Fuels and Chemicals by an authorized administrator of ECI Digital Archives. For more information, please contact

2 Authors B. Shrestha, R. lcese, J. Francois, M. Bettahar, D. Petitjean, and A. Dufour This conference proceeding is available at ECI Digital Archives:

3 Green aromatic bulk-chemicals from lignin pyrolysis vapours R. lcese, B. Shrestha, J. Francois, M. Bettahar, D. Petitjean, A. Dufour CNRS, Université de Lorraine H H H H H H 2 + Iron catalyst R Alkyl Alkyl Aromatics for polymers and fuels - 1 -

4 H H The production of aromatics from lignin is an important challenge for biorefinery Hemicellulose Fermentation or other processes Chemicals Cellulose n Direct application Fibers, paper, etc. H Biomass Fractionation Purification H H H Direct application Plasticizer Gasification Depolymerization Conversion (such as oxidation) Chemicals MACs Hydrotreatment BTX H 2 -rich syngas Frame of this work MACs = xygenated Mono Aromatics Compounds - 2 -

5 Aromatics could be produced by gas-phase hydrodeoxygenation (HD) of pyrolysis vapours H 2 Pyrolysis H H H H H C H 3 H HD over green Fe-based catalyst R Alkyl Alkyl xygenated unstable aromatics + Char + oligomers + CH 4, C 2, C Green distillable aromatics for polymers and fuels - 3 -

6 A green and cheap catalyst is looked for a selective HD of oxygenated pyrolysis products s H H H H Pyrolysis /C Pyrolytic oil Desired route Guaiacol Undesired route Cyclohexanol lcese et al. App. Catal. B. 115 (2012) 63 0 BTX Alkanes H/C - 4 -

7 The HD of guaiacol, a surrogate of pyrolysis products, has been studied over iron-based catalysts. CH 4 -H 2 +H 2 Methanol C, PAH, coke nly for Cobalt catalyst Guaiacol +H 2 Phenol +H 2 -H 2 BT +nh 2 Ring hydrogenated +nh 2 Alkanes, CH 4 Desired products lcese et al. App. Catal. B. 115 (2012)

8 Fe/Si 2 is a selective catalyst for the HD of guaiacol into benzene and toluene Mass residence time= 1/WHSV = g catalyst/(g guaiacol/h) - 6 -

9 Catalytic mechanism of guaiacol HD over Fe/Si 2 I) II) H 2 (gas) H 3 C H H Spill-over Si Si Si Si H H H Fe Si Si Si Si lcese et al. App. Catal. B. 116 (2012)

10 Gas composition has an effect on selectivity lcese et al. App. Catal. B. 129 (2013)

11 Gas composition has an effect on iron speciation and on «coke» composition Iron speciation analysed by XRD & Mössbauer Coke analysed by Temperature Programmed xidation App. Catal. B. 129 (2013)

12 A kinetic model has been developped and included under Aspen Plus for process modeling lcese et al. Energy Fuels 27 (2013)

13 Mass balance of the whole lignin to BTX process is modeled Char and oligomers represent a key issue to improve lignin conversion yields into aromatics lcese et al. Energy Fuels 27 (2013)

14 Experiments have also been conducted on REAL pyrolysis vapours A selective HD has been obtained by iron-based catalysts lcese et al. Energy Fuels 27 (2013)

15 GC*GC and high resolution mass spectrometry («Petroleomic») are complementary methods GC for light, petroleomic for heavier species lcese et al. Energy Fuels 27 (2013)

16 Coke formed by real lignin vapours is very different than coke from guaiacol HD Stack number C 2 flow (µ mol/(min.g cat ) Stack 1 Stack 2 Stack 3 Stack % of Carbon deposit Coke analysed along the length of the fixed bed (profile in coke composition) Temperature (K) 0 Coke plugged micropores of activated carbon but not mesopores of silica lcese et al. ChemSusChem, in press

17 The mechanism of coke formation during the HD of real vapours has been revealed TEM, TP, Petroleomic, GC*GC, N 2 sorption (etc.) were used to reveal this mechanism lcese et al. ChemSusChem, in press

18 Iron is a selective and cheap catalyst for the HD of lignin into aromatics Works are conducted from molecular mechanisms to process integration Thank you for your attention binod.shrestha@univ-lorraine.fr anthony.dufour@univ-lorraine.fr

19 Related papers 1. lcese et al., Applied Catalysis B , pp , Effect of temperature, H 2 pressure and contact time on guaiacol HD over Fe/Si 2 2. lcese et al., Applied Catalysis B 129, pp , Effect of iron loads, support type (Si 2 or carbon) and gas composition on guaiacol HD 3. lcese et al., Energy and Fuels 27 (2), pp , Kinetics and Aspen Plus model of integrated lignin to BTX process 4. lcese et al., Energy and Fuels 27 (4), pp , GC*GC and petroleomic analysis on real lignin vapours HD 5. lcese et al., ChemSusChem, in press Mechanisms of HD of real lignin vapours over Fe/Si 2 and Fe/activated carbon, deactivation and coke formation

20 Simplified scheme of the experimental set-up for guaiacol HD over a fixed bed of catalyst T H 2 N 2 C 4 ways valve Heated lines Syringe pump CH 4 Mass Flow Controllers ven Catalyst bed Vent Fritted µgc - 4 modules n-line analysis (CH 4, H 2, C, etc.) 2 impingers with propanol (-60 C) 6 ways heated valve To on-line GC/FID analysis (heated sample loop) To off-line GC/FID-MS analysis of liquid solutions

21 Simplified scheme of the experimental set-up for real lignin vapours HD Batch lignin pyrolysis connected to an horizontal fixed bed of catalyst, with stacks to investgate the profile of coke deposit along the fixed bed length