DOI: 10.1038/NCHEM.1245 Non-lattice surface oxygen species implicated in the catalytic partial oxidation of decane to oxygenated aromatics Sivaram Pradhan, Jonathan K. Bartley, Donald Bethell, Albert F. Carley, Marco Conte, Stan Golunski, Matthew P. House, Robert L. Jenkins, Rhys Lloyd and Graham J. Hutchings* Cardiff Catalysis Institute, School of Chemistry, Cardiff University, CF10 3AT, UK Email: Hutch@cardiff.ac.uk Contents Figure S1: TPR of iron molybdate catalyst Table S1: Surface analysis (atomic composition) of iron molybdate catalyst by XPS Table S2: Estimation of lattice oxygen consumed during reaction Table S3: Crystalline phase composition of iron molybdate catalyst Table S4: BET surface area of iron molybdate catalyst after different pre-treatments Table S5: Product speciation NATURE CHEMISTRY www.nature.com/naturechemistry 1
Figure S1: TPR of iron molybdate catalyst Measured TPR profile: Interpretation of TPR profile: Reduction peak Measured peak temperature ( o C) Reported [22] peak temperature ( o C) Phases formed [ref 22 in manuscript] As prepared Fe 2 (MoO 4 ) 3 and MoO 3 1 580 580 MoO 3, α- FeMoO 4, β-femoo 4, Mo 4 O 11 2 620 637 MoO 2, α- FeMoO 4, β-femoo 4, Mo 4 O 11 3 690 679 MoO 2, Fe 3 O 4, Fe 2 Mo 3 O 8, α- FeMoO 4, β-femoo 4 4 740 741 MoO 2, Fe 3 O 4, Fe 2 Mo 3 O 8, Fe 3 Mo (minor) 5 >900 960 Mo o, Fe 3 Mo alloy NATURE CHEMISTRY www.nature.com/naturechemistry 2
Table S1: Surface analysis (atomic composition) of iron molybdate catalyst by XPS Pre-treatment % Fe % Mo % O Fe/Mo Mo/Fe None (as prepared) 5.9 23.9 70.2 0.25 4.1 350 ºC / 12 h oxidative reaction 4.9 20.5 74.6 0.24 4.2 350 ºC / 12 h oxidative reaction / 12 reaction without O 2 3.8 22.3 73.8 0.17 5.9 350 ºC / 12 h oxidative reaction / 12 reaction without O 2 / 12 h oxidative reaction 6.7 21.9 71.4 0.31 3.3 Table S2: Estimation of lattice oxygen consumed during reaction NATURE CHEMISTRY www.nature.com/naturechemistry 3
Table S3: Crystalline phase composition of iron molybdate catalyst Pre-treatment Fe 2 (MoO 4 ) 3 MoO 3 FeMoO 4 MoO 2 Mo 4 O 11 (wt %) (wt %) (wt %) (wt %) (wt %) None (as prepared) 81 19 - - - 350 C / 12 h oxidative reaction 88 12 - - - 350 C / 12 h oxidative reaction / 12h reaction without O 2 - - 55 19 26 350 C / 12 h oxidative reaction / 12h without O 2 / 12 h with O 2 restored - - 62 26 12 460 C / 12 h oxidative reaction conditions - - 60 21 19 460 C / 12 h oxidative reaction / 12h reaction without O 2 - - 56 25 19 460 C / 12 h oxidative reaction / 12h without O 2 / 12 h with O 2 restored - - 47 35 18 Table S4: BET surface area of iron molybdate catalyst after different pre-treatments Pre-treatment Surface area (m 2 g -1 ) None (as prepared) 8 350 C / 12 h oxidative reaction 22 350 C / 12 h oxidative reaction / 12h reaction without O 2 14 460 C / 12 h oxidative reaction conditions 10 460 C / 12 h oxidative reaction / 12h reaction without O 2 22 NATURE CHEMISTRY www.nature.com/naturechemistry 4
Table S5: Product speciation Conversion and selectivity of n-decane during oxidative reaction in blank reactor, 0.80% n-decane, C:O = 14.8:1 Selectivity (%) Temp ( o C) C (%) C 1 -C 7 Decene Oxygenated aromatics Others CO CO 2 350 0.0 0.0 0.0 0.0 0.0 0.0 0.0 400 0.0 0.0 0.0 0.0 0.0 0.0 0.0 420 0.4 1.8 78.9 0.0 0.0 0.0 19.3 440 0.6 2.5 58.4 0.0 16.0 0.0 23.1 460 0.9 5.6 36.7 0.0 24.5 6.2 27.0 Conversion and selectivity of n-decane during oxidative reaction over iron molybdate catalyst, 1% n-decane, C:O = 11.8:1. Temperature (ºC) 250 300 350 350 350 350 350 350 Conversion (%) 0.41 2.41 3.50 3.88 3.78 3.75 3.62 4.03 Ethane/ene 0.05 0.05 0.04 0.01 0.03 0.05 0.01 0.01 Propane/ene 0.04 0.04 0.02 0.24 0.08 0.02 0.07 0.07 Butane 0.00 0.00 0.02 0.00 0.00 0.00 0.03 0.03 Pentane 0.00 0.21 0.21 0.16 0.05 0.17 0.07 0.05 Hexane 0.00 0.07 0.08 0.12 0.23 0.27 0.25 0.21 Methanol 0.00 0.00 0.38 0.10 0.35 0.42 0.43 0.42 Propanol 0.00 0.05 0.07 0.07 0.07 0.09 0.09 0.09 Butanol 0.00 0.00 0.14 0.14 0.12 0.40 0.14 0.43 Pentanol 0.00 0.00 0.20 0.17 0.16 0.15 0.16 0.14 Pentanoic Acid 0.00 2.64 1.93 1.88 1.88 3.03 3.78 3.62 Decene 3.10 2.86 10.60 10.75 10.14 8.17 9.04 8.14 Phthalic Anhydride 0.00 13.71 13.81 12.04 13.20 11.62 11.19 11.34 Coumarin 0.00 5.12 3.82 5.28 4.64 2.46 2.82 1.91 Napthol 0.00 3.37 1.32 4.17 2.62 2.72 2.62 2.47 9-Fluorenone 0.00 0.27 2.00 0.88 1.53 1.49 1.66 1.59 Xanthone 0.00 0.41 0.99 1.51 1.35 0.33 0.87 0.58 Napthalene 0.00 0.00 0.22 0.12 0.08 0.09 0.13 0.11 2-Ethyl Napthalene 0.00 1.31 0.00 2.00 1.53 1.31 1.33 1.30 Fluorene 0.00 2.39 2.10 1.38 1.22 1.04 1.64 1.53 C 10 Aromatics( All having Molecular weight 132) 0.00 0.58 2.04 1.50 1.76 1.71 1.34 2.41 Other C 10 Aromatic Oxygenates 0.00 0.59 2.30 2.51 2.84 2.97 2.80 3.11 CO 95.81 60.16 51.16 48.87 50.55 51.77 52.87 53.29 CO 2 0.00 5.80 8.44 6.21 7.44 9.98 7.41 7.24 C Balance (%) 96.19 80.35 83.32 78.46 78.59 96.36 98.03 90.20 NATURE CHEMISTRY www.nature.com/naturechemistry 5
Conversion and selectivity of n-decane during oxidative reaction over iron molybdate catalyst at 460 C, 0.92% n-decane,c:o = 11.7:1. Time (h) 1 3 5 7 9 12 Conversion (%) 9.5 9.5 9.6 8.9 9.1 8.8 Methane 0.0 0.0 0.0 0.0 0.0 0.0 Ethane/ene 0.1 0.1 0.1 0.1 0.1 0.1 Propane/ene 0.1 0.1 0.1 0.1 0.1 0.1 Butane 0.0 0.0 0.0 0.2 0.0 0.0 Pentane 0.1 0.0 0.0 0.1 0.0 0.1 Hexane 0.1 0.1 0.1 0.2 0.1 0.1 Heptane 0.1 0.1 0.1 0.2 0.1 0.1 Octane 0.2 0.1 0.1 0.2 0.1 0.1 Methanol 0.3 0.3 0.3 0.0 0.3 0.2 Propanol 0.1 0.1 0.1 0.1 0.1 0.6 Butanone 0.2 0.2 0.2 0.1 0.1 0.2 Propionic Acid 0.2 0.2 0.2 0.1 0.1 0.3 Pentanol 2.3 2.0 1.9 1.8 1.7 1.3 Pentanoic Acid 0.1 0.1 0.1 0.0 0.1 0.1 Hexanol 0.0 0.0 0.2 0.1 0.2 0.1 Hexanoic Acid 0.2 0.2 0.0 0.0 0.0 0.0 Heptanol 0.2 0.2 0.2 0.0 0.2 0.1 Decene 30.1 29.4 29.5 30.7 29.8 29.9 Toluene 0.4 0.3 0.3 0.3 0.2 0.1 Styrene 0.4 0.3 0.3 0.1 0.2 0.2 Phthalic Anhydride 0.1 0.1 0.1 0.1 0.1 0.2 1-Indanone 0.0 0.1 0.1 0.1 0.1 0.1 Coumarin 0.0 0.1 0.1 0.1 0.0 0.2 Napthol 0.0 0.0 0.0 0.0 0.0 0.0 9-Fluorenone 0.1 0.3 0.4 0.4 0.4 0.5 Xanthone 0.1 0.1 0.1 0.1 0.1 0.2 Napthalene 1.0 0.8 0.8 0.6 0.6 0.5 2-Ethyl Napthalene 0.3 0.2 0.1 0.2 0.2 0.2 C 10 Aromatics( All having Molecular weight 132) 33.4 29.4 28.1 28.0 26.6 23.0 Other C 10 Aromatic Oxygenates 0.2 0.4 0.2 0.4 0.4 0.5 CO 1.7 1.5 2.2 1.0 1.1 2.4 CO 2 28.2 33.2 34.3 34.9 37.0 39.1 C Balance (%) 96.5 97.8 94.0 97.6 92.0 90.5 NATURE CHEMISTRY www.nature.com/naturechemistry 6
Conversion and selectivity of n-decane during oxidative reaction over iron molybdate catalyst at 460 C, 0.92% n-decane. Time (h) 0.5 1 5 9 12 Conversion (%) 2.93 3.09 2.78 2.42 2.40 Methane 0.02 0.00 0.03 0.03 0.02 Ethane/ene 0.11 0.05 0.11 0.12 0.12 Propane/ene 0.18 0.17 0.18 0.19 0.18 Butane 0.03 0.22 0.24 0.00 0.02 Pentane 0.00 0.22 0.07 0.08 0.24 Hexane 0.11 0.08 0.33 0.13 0.36 Heptane 0.13 0.28 0.32 0.16 0.14 Octane 0.22 0.29 0.35 0.29 0.24 Methanol 0.44 0.52 0.15 0.20 0.23 Propanol 0.10 0.05 0.11 0.12 0.08 Propionic Acid 0.32 0.14 0.22 0.37 0.35 Pentanol 1.48 1.40 0.55 0.42 0.31 Pentanoic Acid 0.18 0.20 0.16 0.15 0.13 Hexanone 0.32 0.23 0.36 0.41 0.38 Heptanone 0.33 0.30 0.63 0.47 0.46 Decene 48.28 46.65 51.29 58.31 56.42 Toluene 0.40 0.39 0.31 0.28 0.22 Styrene 0.32 0.53 0.29 0.52 0.42 Napthalene 1.32 0.00 0.00 0.00 0.00 C 10 Aromatics( All having Molecular weight 132) 46.17 48.26 44.56 38.07 40.14 C Balance (%) 91.49 98.46 95.62 95.55 101.87 NATURE CHEMISTRY www.nature.com/naturechemistry 7
Conversion and selectivity of n-decane during oxidative reaction after 12 h under aerobic conditions then 12 h under anaerobic conditions over iron molybdate catalyst at 460 C, C:O = 11.7:1, 0.92% n-decane Time (h) 0.5 1 5 9 12 Conversion (%) 8.18 7.87 7.58 7.66 8.13 Methane 0.02 0.02 0.02 0.02 0.02 Ethane/ene 0.08 0.08 0.07 0.07 0.07 Propane/ene 0.08 0.08 0.08 0.08 0.08 Butane 0.01 0.01 0.22 0.22 0.05 Pentane 0.12 0.13 0.12 0.11 0.19 Hexane 0.07 0.07 0.05 0.13 0.13 Heptane 0.06 0.08 0.06 0.13 0.11 Octane 0.08 0.08 0.08 0.13 0.07 Methanol 0.28 0.29 0.01 0.07 0.27 Propanol 0.05 0.05 0.04 0.05 0.07 Butanol 0.12 0.12 0.11 0.11 0.08 Propionic Acid 0.14 0.14 0.01 0.06 0.05 Pentanol 1.12 1.12 1.02 1.01 0.95 Pentanoic Acid 0.08 0.08 0.07 0.06 0.09 Hexanoic Acid 0.16 0.12 0.13 0.08 0.09 Heptanone 0.07 0.11 0.12 0.09 0.08 Decene 29.69 30.35 30.99 30.99 28.85 Toluene 0.12 0.12 0.10 0.10 0.09 Styrene 0.18 0.20 0.18 0.10 0.28 Phthalic Anhydride 0.28 0.35 0.62 0.82 0.86 1-Indanone 0.16 0.17 0.15 0.17 0.16 Coumarin 0.31 0.33 0.35 0.39 0.36 Napthol 1.08 0.00 0.00 0.00 0.00 9-Fluorenone 0.21 0.56 0.51 0.61 0.53 Xanthone 0.36 0.20 0.18 0.17 0.24 Napthalene 0.47 0.49 0.45 0.48 0.39 2-Ethyl Napthalene 0.16 0.16 0.16 0.17 0.17 C 10 Aromatics( All having Molecular weight 132) 23.00 22.94 21.64 22.11 21.38 Other C 10 Aromatic Oxygenates 0.00 0.53 0.47 0.54 0.49 CO 3.83 2.42 3.77 3.25 3.38 CO 2 37.84 38.57 38.27 37.74 40.70 C Balance (%) 99.25 101.38 102.40 103.01 93.29 NATURE CHEMISTRY www.nature.com/naturechemistry 8