Supporting Information

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1 Supporting Information Deoxygenation of Palmitic Acid on Unsupported Transition Metal Phosphides Marco Peroni, a Insu Lee, a Xiaoyang Huang, a Eszter Baráth, a Oliver Y. Gutiérrez, a * Johannes A. Lercher a,b * a Technische Universität München, Department of Chemistry, Catalysis Research Center, Lichtenbergstraße 4, Garching (Germany) b Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA (USA) Present address: Institute for Integrated Catalysis, Pacific Northwest National Laboratory, P.O. Box 999, Richland, WA (USA) * Corresponding authors. Fax: address: oliver.gutierrez@pnnl.gov (O.Y. Gutiérrez) johannes.lercher@ch.tum.de (J.A. Lercher)

2 Fatty acid composition in triglyceride mixture of microalgae oil The crude microalgae oil was obtained by Verfahrenstechnik Schwedt GmbH, the composition described in Table S1 was first reported in B. Peng, X. Yuan, C. Zhao, J. A. Lercher, Stabilizing catalytic pathways via redundancy: selective reduction of microalgae oil to alkanes., J. Am. Chem. Soc., 212, 134, Table S1. Fatty acid composition in triglyceride mixture of microalgae oil, wt. %. C 14:.4 C 16: 4.41 C 18: C 18: C 18: 4.41 C 2:4.7 C 2:.43 C 22:6.13 C 22:4.19 C 22:1.97 C 22:.44 C 24:.36 Sterol.12 Nomenclature in lipid numbers: C X:Y : x number of carbon atoms in fatty acid chain; y number of double bonds in fatty acid chain. Verification of mass transport limitations Table S2. Reaction rates for the conversion of palmitic acid obtained at 24 C and 4 bar using different amounts and particle size of catalyst. Catalyst Rate 1, Rate 2, mmol pa (g cat h) -1 mmol pa (g cat h) -1 Rate 3, mmol pa (g cat h) -1 Ni 2 P-CA n.d n.d. 1 Rates obtained with 4 mg of catalyst µm 2 Rates obtained with 1 mg of catalyst µm 3 Rates obtained with 4 mg of catalyst and particle size of µm

3 The possibility of internal diffusion limitation was also assessed by calculating the effectiveness factor and Weisz Modulus under our reaction conditions as described in the following. Binary diffusion coefficient of hexadecanoic acid in dodecane was calculated following the empirical Wilke-Chang formula: =7.4 1 ( ) / D AB Binary diffusion coefficient of solute A in solvent B (8.76х1-4 cm 2 s -1 ) T Temperature ( K) µ B Dynamic viscosity of solvent at T (.16 cp; obtained by extrapolation from 473 K to K) x Association parameter (1 for hydrocarbons) M A Molecular weight of solvent (17.34 g mol -1 ) V A Molecular volume of solute at normal boiling point (379 cm 3 mol -1, using additive method according to Le Bas). The binary diffusion coefficient D AB was then used to calculate an effective diffusion coefficient for the diffusion in the catalyst pores:, = (1 ) = 1 D AB,pore Effective diffusion coefficient in porous solid (4.99x1-5 cm 2 s -1 ) D AB Binary diffusion coefficient in bulk (8.76х1-4 cm 2 s -1 ) λ Hindrance factor (.13) d s Effective (smallest) diameter of solute (5 Å for linear hydrocarbons) Diameter of pores (38.19 Å, median pore diameter from BJH analysis) d p Calculation of the Thiele modulus and effectiveness factor (for a spherical particle): = 3, = tanh () = φ Thiele modulus (calculated for different particle radii) R p Particle radius η Effectiveness k obs Observed rate constant k True rate constant in absence of mass transfer limitations D AB,pore Effective diffusion coefficient in porous solids (4.99x1-5 cm 2 s -1 ) The two expressions for the Thiele modulus φ and effectiveness η were then combined and iteratively solved for k at different particle radii. The results are schematically shown in Figure S1. The Weisz modulus is also shown in the figure as calculated according to:

4 Ѱ= Figure S1. Effectiveness factor and Weisz Modulus in function of particle diameter. Both parameters point to the absence of internal mass transfer limitation for particles smaller than 28 µm. Calculation of kinetic parameters and first order rate constants Conversions and yields were calculated following classical definitions as shown in Equations (1) (3), where Ca, and Ca f are the concentrations of the reactant in the feed and in the effluent, and Ci is the concentration of the product i in the effluent. The concentrations of all products were determined by applying the corresponding response factors obtained from calibrations with pure compounds. [%]= 1 (1) [%]= 1 (2) [%]= (3) The first order rate constants were calculated considering the following form of the empiric rate equation (H 2 is in large excess and was not changed in typical experiments), where C is concentration of palmitic acid (PA), k the rate constant, t is residence time, and m is the reaction order in palmitic acid:

5 . = Integration for = for = (for =1) gives the formula: ln.. ln.. = ln.... = Conversion (X) was defined as (C PA and C PA are the concentrations of palmitic acid at any time and the initial concentration, respectively): = therefore conversion and rate constant are related as: =1.... ln(1 )= =>= ln(1 ) Characterization of oxide precursors The oxide catalyst precursors (prior to temperature programmed reduction) were characterized only by XRD (Figure S1). MoO 3 (ICOD: -1-76), and Ni 2 P 4 O 12 (ICOD: ) were the only crystalline species identified in the oxide precursors of MoP and Ni 2 P, respectively. With the presence of citric acid during the synthesis, the intensity of the XRD reflections decreased pointing to smaller crystalline domains. The precursors of WP only exhibited signals of amorphous phases. Their intensity, however, also decreased with the use of citric acid. The same trend, i.e., reduced crystal sizes by using citric acid was observed for the phosphide materials as described in the main text.

6 Intensity, a.u. * * * ** * * MoP WP Ni 2 P-CA2 Ni 2 P θ, Figure S2. X-ray diffractograms of the oxide precursors (materials before temperature programmed reduction) of the phosphides. The labels show to the names of the corresponding phosphides. The reflections in the patterns of Ni 2 P and Ni 2 P-CA2 are assigned to Ni 2 P 4 O 12. The reflections of MoP labeled with (*) are assigned to MoO 3. Characterization of CA-phosphide materials Volume Adsorbed, cm 3 g -1 STP (a) (c) (b) (d).5 1 Relative pressure, P P -1 o Figure S3. N 2 physisorption isotherms of Ni 2 P-CA1 (a), Ni 2 P-CA2 (b), (c), and (d).

7 Intensity, a.u. Standard (HMFI) Ni 2 P-CA1 Ni 2 P-CA Figure S4. NH 3 desorption profiles from CA-phosphide materials and from the reference HMFI (SiO 2 /Al 2 O 3 molar ratio of 9). Intensity, a.u. A Ni 2 P-CA2 Intensity, a.u B Ni 2 P-CA Figure S5. TPD of n-propylamine: (A) NH 3 desorption profiles; (B) unreacted n-propylamine desorption profiles.

8 Time on stream results Stabilization 3 C 28 C 26 C 24 C 22 C 2 C 18 C 3 C TOS, h Figure S6. Conversion of palmitic acid at varying temperature along time on stream (TOS) on Ni 2 P-CA2 (+), ( ), and ( ). Palmitic acid (.37 M) in dodecane, WHSV 1 h -1, 4 bar H 2. Catalytic tests at constant temperature Figure S7. Conversion of palmitic acid at varying residence time on Ni 2 P-CA2 (+), ( ), and ( ). Palmitic acid (.37 M) in dodecane, 24 C, 4 bar H 2, H 2 /palmitic acid molar ratio = 1. The lines are to guide the eye.

9 Yield, % Yield, % Yield, % Yield, % Yield, % 1 12 Ni 2 P-CA Yield, % Figure S8. Left plots: Yields of pentadecane ( ), hexadecane and hexadecene ( ), hexadecanal ( ), hexadecanol (x) and palmityl palmitate ( ) at different contact times on CA-phosphides. Right plots: Selectivtiy of pentadecane ( ), hexadecane and hexadecene ( ), hexadecanal ( ), hexadecanol (x) and palmityl palmitate ( ) at different conversions on CA-phosphides. Palmitic acid (.37 M) in dodecane, 24 C, 4 bar H 2. The lines are to guide the eye. Selectivity, % Selectivity, % Selectivity, % 7 Ni 6 2 P-CA

10 Conversion of hexadecanol at varying temperatures 5 Ni 2 P-CA Selectivity, % Selectivity, % 1 Ni 2 P-CA Selectivity, % Figure S9. Left plots: Conversion of hexadecanol on Ni 2 P-CA2 (A), (B) and (C) at varying temperatures. Conversion ( ), pentadecane ( ), hexadecane ( ), hexadecene ( ), hexadecanal ( ). Hexadecanol (.37 M) in dodecane, WHSV = 1 h -1, 4 bar H 2. Right plots: Selectivity of pentadecane ( ), hexadecane ( ), hexadecene ( ), hexadecanal ( ) at different hexadecanol conversions on Ni 2 P-CA2,, and. Hexadecanol (.37 M) in dodecane, 26 C, 4 bar H 2. The lines are to guide the eye.

11 2 1-1 lnk -2 Ea = 123 kj/mol Ea = 124 kj/mol -3-4 Ea = 126 kj/mol /T Figure S1. Conversion of hexadecanol at different temperature. Ni 2 P-CA2 (+), WP CA ( ), MoP CA ( ). Hexadecanol (.37 M) in dodecane, WHSV 1 h -1, 4 bar H 2, H 2 /hexadecanol molar ratio = 1. Conversion of hexadecanal at varying temperatures A B Figure S11. Conversion of hexadecanal on (A) Ni 2 P-CA2 and (B) at different temperatures. Conversion ( ), pentadecane ( ), hexadecane ( ), hexadecanol (x). Hexadecanal (.37 M) in dodecane, WHSV = 1 h -1, 4 bar H 2. The lines are to guide the eye.

12 Study of the carbon loss mechanism on Ni 2 P-CA Figure S12. Transient experiments on Ni 2 P in order to study the carbon loss mechanism switching from H 2 to N 2 at 4 bar and contact time of 2.5 h. Stabilization: 16 h at 24 C in H 2 and contact time.8 h. (A) Yield % distribution. (B) Concentration in mol/l of CO and CO 2.

13 Conversion of microalgae oil on MoP A B Figure S13. Conversion of microalgae oil on MoP at (A) different temperatures (WHSV = 1 h -1 ) and at (B) different WHSV (26 C). Microalgae oil (.12 M) in dodecane, 4 bar H 2. Conversion ( ), pentadecane ( ), hexadecane ( ), heptadecane (x), octadecane (+), stearic acid ( ), palmitic acid ( ), other alkanes (*). The lines are to guide the eye.