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Design Group

Design Group. Vincent Piepiora Suzanne Rapp Pablo Celestino. Synthesis to covert syngas to EtOH and HA. Synthesis to convert syngas to EtOH and HA. Main Processes: Intermediary process: Catalysts for: Direct Synthesis Methanol synthesis Direct synthesis F-T synthesis F-T synthesis

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Design Group

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  1. Design Group Vincent Piepiora Suzanne Rapp Pablo Celestino

  2. Synthesis to covert syngas to EtOH and HA

  3. Synthesis to convert syngas to EtOH and HA Main Processes:Intermediary process:Catalysts for: Direct Synthesis Methanol synthesis Direct synthesis F-T synthesis F-T synthesis Methanol Homologation Methanol homologation ENSOL process ENSOL process Focus on: MoS2-based catalyst F-T synthesis/Direct synthesis

  4. Homogenous More selective to EtOH Expensive Separation and recirculation is difficult Heterogeneous Suitaible for continuos process Low yield and selectivity to EtOH Catalysts

  5. Noble metals-based Primarily supported by Rh catalyst Expensive and limited amount Non-noble metals-based Used in MeOH synthesis, F-T synthesis and Direct synthesis Produce mixture of C1-C6 alcohols High selectivity toward MeOH and isobutOH Little selectivity toward EtOH Heterogeneous

  6. Alkali promoters • They play a significant role in activity, selectivity toward HA and lifetime of the catalysts. • Addition of alkali promoters increase the higher alcohol production in the order of Li<Na<K<Cs>Rb • Helps to suppress the formation of HC • Catlayst doping with a small amount of alkali usually increases the reaction rate. • F-T synthesis catalyst and MoS2-based catalyst - optimum alkali loading of 10 wt% and 20 wt% respectively to achieve a max selectivity for EtOH and HA.

  7. MoS2-based catalyst- Pos. compared to other catalysts: • Sulphur resistant • Less severe coke deposition - even with a syngas having a low H2/CO ratio • Favours the formation of linear alcohols with a high selectivity to EtOH • Less sensitive to CO2 in the syngas stream compared to other alcohol synthesis catalysts • Requires a sulphur content (H2S) of 50-100ppm

  8. MoS2-based catalyst • Without alkali-doping: primarily CH4 in product. • With alkali-doping: the selectivity will be shifted toward alcohols. • Ni promoted MoS2-based catalyst decreases the MeOH selectivity and increases the selectivity toward C2+ higher alcohols, especially EtOH. - HC formation, due to Ni addition, could be suppressed by modifying the catalyst with La.

  9. Catalyst K2CO3NiMoS2 MoS2 (Dow Chemical Company) Temperature [oC] 320 or 280 295 Pressure [psig] 1160 1050 Space velocity [1/h] 2500 1300 H2/CO 1 1 Carbon selectivity to EtOH [%] 15.4 or 27.2 40.7 Carbon selectivity to MeOH [%] 6.2 or 10.8 22.7 MoS2-based catalyst

  10. Catalyst Nanosized MoS2 patented by PowerEnterCat., Inc. Temperature [oC] 200-300 Pressure [psig] 500-3000 Space time [mg/(g cat h)] 400 Requirements Small amount of sulfur in the syngas stream or directly added to the reactor vessel Pilot plant planned[gal/d] 500 Ecalene HAS process

  11. Direct synthesis of syngas to EtOH and HA • 2CO(g) + 4H2(g) => CH3CH2OH(g) + H2O(g) • Water-gas shift reaction: CO(g) + H2O(g) => CO2(g) + H2(g) • Side reactions, formation of: - CH4 - C2-C5 alkanes and olefins - ketones, aldehydes, esters and acetic acid • Methanation reaction: CO(g) + 3H2(g) => CH4(g) + H2O(g)

  12. BIOMASS Composition

  13. Gasifier Accept 3/16’’ particule size Fluidized Bed (10MW) Entrained Flow(100MW)

  14. Cleaner Inorganic Cleaner Dust Cleaner Hydrosulfur Cleaner (Mo and Co Catalyst)

  15. Fischer-Tropsch process

  16. Fischer-Tropsch Catalyst

  17. Fischer-Tropsch Catalyst

  18. Fischer-Tropsch Catalyst High pressure, 573K and low reaction time

  19. Fischer-Tropsch Catalyst Questions, What do we do with HC gas and MeOH?

  20. Reactor Election CATALYST DEACTIVATION • Syngas to Alcohol  highly exothermic reaction • High Temperature: • Steam process generation • Heat transfer limitations in catalyst  Hotspots

  21. Single Fixed Bed Reactor • Simple design and easy to scale-up • Heat transfer limitations • Use of jacket with counter-current water steam production • Importance of catalyst deactivation: it has to be taken in account for the design

  22. Two-Step Fixed Bed Reactor • Due to thermodinamics and kinetics: • Low T favours methanol production • High T favours C-C bonding (HA production) • Use of fixed bed reactor with 2 steps • Use of special catalysts: • Cu based catalyst for low T (325°C) • Zn-chromite catalyst for high T (405°C)

  23. Slurry Reactor • Uses up to 50 wt% catalyst dispersed in inert hydrocarbon oil • Catalyst is pulverized in small particles Heat and mass transfer limitations minimized

  24. Slurry Reactor • Advantages: • Low heat and mass limitations • Excellent heat removal  Good T control • Efficient conversion of heat into steam • Lower abrasion compared to fluidized reactor • Capability of mixing different catalysts • Disadvantages: • Much longer residence time  more consecutive reactions

  25. Recirculating Unreacted Species • After the reactor, the hot gas stream can be cooled down in a condenser: • Gas stream: H2, CO, CO2, CH4 • Liquid stream: MeOH, EtOH, HA, water, byproducts • Gas stream  different options: • Combustion: electricity or steam process • Recirculation: to the reactor or the digester

  26. Recirculating Unreacted Species • Liquid stream: • Simple distillation to separate methanol • MeOH: intermediate specie for HA production can be recycled to the reactor to increase alcohol yield • Complete conversion of MeOH into EtOH after 7-8 cycles in the FT reactor

  27. Alcohol Separation • Liquid stream: • Contains EtOH, HA, water and byproducts • We want a fuel  water has to be separated • Problem: azeotrope bewteen EtOH and water difficulties for distillation • Availability of different techniques: • Azeotropic distillation, solvent extraction, molecular sieve, membrane technology, etc.

  28. Questions?

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