Highly Dispersed Bimetallic Catalysts for Fischer-Tropsch Reaction

1. Synthesis, Characterization and Evaluation of Highly Dispersed Bimetallic Catalysts for Fischer-TropschReaction John Meynard M. Tengco,WeijianDiao, John R. Monnier and John R. Regalbuto* University of South Carolina, Columbia, South Carolina 29208 (USA) June 6, 2013

2. Fischer – Tropsch Synthesis • Syngas (CO, H2) • High P, Moderate T • Adsorption  CO dissociation  C addition  Hydrogenation • Longer chain HC’s • CO dissociation may be efficient • Hydrogenation issues • C buildup (fouling) • Loss of active sites • CO dissociation should be coupled with facile hydrogenation to prevent carbonaceous deposit buildup • Hypothesis: We can use Electroless Deposition (ED) to rationally synthesize a Pt-promoted bimetallic catalyst with the required high degree of metal 1 – metal 2 interaction.

3. Rationale for Bimetallic Catalyst Synthesis • Combine properties of individual catalyst components • Effective C-O dissociation (e.g. Ru, Fe, Co) • Good Hydrogenation Activity (e.g. Pt) vs

4. Electroless Deposition (ED) • (A) Immersion in electroless developer bath, (B) activation with reducing agent, RA; (C) reduction-deposition of second metal, (D) catalytic ED, (E) auto-catalytic ED • Catalytic to auto-catalytic ED can produce core-shell

5. Galvanic Displacement • Proceeds as long as primary metal can be oxidized and reduction of secondary metal is favored (galvanic exchange)

6. Experiment Outline • Catalyst Preparation • Monometallic Catalysts • Proof of principle done on SiO2 support instead of C • Bimetallic Catalyst Synthesis • Characterization • XRD, STEM, Chemisorption, TPR of O-precovered catalyst • Evaluation • Preliminary reaction results

7. Monometallic Catalyst Preparation

8. Bimetallic Catalyst Preparation (ED) • Target θtheo=0.5ML Pt, based on active sites determined by chemisorption • Pt precursor: H2PtCl6 • Reducing Agent: DMAB • Sodium Citrate for bath stability • DMAB : NaCit : Pt = 6/5/1 • pH 10, 70°C • 1.5g catalyst in 300mL (0.5g/100mL)

9. Bimetallic Catalyst Preparation (DI)

10. Catalyst Characterization: XRD • 4.5nm particle size for Ru • Presence of Pt peaks in DI sample (separate phase)

11. Catalyst Characterization: XRD • 3nm particle size for Co in calcined (as Co3O4) and reduced sample • DI and ED sample have different (I still have to figure this out) phase

12. Catalyst Characterization: XRD • 3nm particle size for Co in calcined (as Co3O4) and reduced sample • DI and ED sample have different (I still have to figure this out) phase

13. Catalyst Characterization • TPR of O pre-covered catalyst • (currently doing this) • Done (4): Ru, Pt(ED)-Ru, Co, Fe, • Running: Pt(ED)-Co • To be done(4): Pt(ED)-Fe, Pt(DI) series

14. Catalyst CharacterizationTPR of O-precovered catalyst

15. Catalyst Characterization

16. Catalyst Characterization

17. Catalyst Characterization • STEM??

18. Catalyst Characterization • STEM??

19. Reaction Data (Preliminary Results) • DATA