Upgrading In Situ Catalytic Pyrolysis Bio-oil to Liquid Hydrocarbons Douglas Elliott, Daniel Santosa, Mariefel Olarte Pacific Northwest National Laboratory Yrjö Solantausta, Ville Paasikallio VTT Technical Research Centre of Finland Foster Agblevor Utah State University
In Situ Catalytic Pyrolysis and Hydrotreating. Bio-oil product from catalytic pyrolysis upgraded by catalytic hydrotreating In situ catalytic pyrolysis combines pyrolysis and catalytic cracking into one step In situ catalytic pyrolysis Catalytic pyrolysis bio-oil Catalytic hydrotreating Hydrocarbon liquid product Product fractionation to fuels
In Situ Catalytic Pyrolysis and Hydrotreating. Improved bio-oil product quality by catalytic pyrolysis facilitates upgrading by catalytic hydrotreating More thermally stable bio-oil eliminates stabilization requirement Reduced oxygen content means lower hydrogen requirement; however, higher aromatic content may increase consumption Two-phase product allows simple removal of light oxygenates which contributes to the first two bullets Phase separation removes water and reduces hydrotreater reactor size requirement Counter-balancing issues in catalytic pyrolysis Catalyst stability in pyrolysis Lower yield of bio-oil
Comparison of Fast Pyrolysis Bio-oil and in situ Catalytic Pyrolysis Bio-oil C H 0 by diff TAN viscosity density moisture % dry basis mg KOH/kg cps g/ml % Bio-oil (typical)* 53.4 6.5 40.0 71 21@40 C 1.21 23.9 ZSM-5 catalyzed 71.5 6.5 21.9 57 445@40 C 1.17 6.0 * Oasmaa et al. Energy Fuels 2010, 24, 1380-1388 VTT system diagram Operating Parameters Spray dried HZSM-5 catalyst from Zeolyst, SiO 2 /Al 2 O 3 ratio 50, average particle size 78 µm, zeolite content 50 % Pyrolysis temperature 520 C, regeneration temperature 650-670 C Fluidization velocity 4 m/s Biomass feeding rate 20 kg/h, catalyst-to-biomass ratio 7 (wt/wt)
Component Comparison of Fast Pyrolysis Bio-oil and in situ Catalytic Pyrolysis Bio-oil GC-MS Bio-oil* ZSM-5 catalyzed Percent, based on total ion count of chromatograph aromatic hydrocarbons 0 29 phenolics 29 18 other oxygenates 56 13 unidentified 14 40 Flash Point 61.5 C 45.5 C ICP-OES ppm Si ND 1532 Al ND 333 K 22 82 Ca 23 51 * PNNL bio-oil from pine
Comparison of Fast Pyrolysis Bio-oil and in situ Catalytic Pyrolysis Bio-oil C H 0 by diff TAN viscosity density moisture % dry basis mg KOH/kg cps g/ml % Bio-oil (typical)* 53.4 6.5 40.0 71 21@40 C 1.21 23.9 Red mud catalyzed 67.9 7.1 24.8 47 75@40 C 1.13 3.5 * Oasmaa et al. Energy Fuels 2010, 24, 1380-1388 USU system diagram 1- Fluidized bed reactor 3- Thermocouple 4- Mass flow controller 5- jacketed air-cooled feeder tube 6- Hopper 7- Screw feeder 8- Computer 9- Heating tape 10-Hot gas filter 11-Reservoir 12-Condenser 13-ESP 14-AC power supply 15-Filter 16-Wet gas meter 17-Gas chromatograph Operating Parameters Temperature = 450 C Fluidizing gas flow rate = N 2 @ 0.4 SCFM + NCG@2.0 SCFM) Biomass feed rate = 1kg/h Catalyst loading = 1 kg Run time = 4 h
Comparison of Fast Pyrolysis Bio-oil and in situ Catalytic Pyrolysis Bio-oils Bio-oil ZSM-5 catalyzed Red mud catalyzed 13 C NMR Percent, based on total carbon signal aromatic 32.3 51.9 46.8 phenolic 14.0 17.7 15.1 total aliphatic 15.4 16.1 20.1 carbonyl 4.2 5.4 5.3 carboxyl 6.2 1.9 2.5 alcohols, sugars 22.4 2.1 7.6 ether 5.4 5.0 2.6 31 P NMR mmol OH / g bio-oil phenolic 3.89 4.35 aliphatic 0.95 2.55 carboxyl 0.37 0.49 Carbonyl titration, mmol/g dry basis 5.3 3.5 2.6
Continuous-flow, Fixed-bed Catalytic Hydrotreating PNNL system diagram Operating Parameters ZSM-5 Red mud Temperature, C 400 400 Pressure, psig 1800 1780 LHSV, L/L/h 0.12 0.13-0.15 H 2 /bio-oil, L/L 2550 2550 Time on stream 64* 176-307 h catalyst CoMoS CoMoS Bed volume, ml 33 19 * Bed plugged at entrance with Al
Processing Results -- ZSM-5 Catalyzed Feedstock product sample H/C O TAN density moisture hydrogen consumption atom ratio wt % mg KOH/ g oil product g/ml wt% g/g dry biooil feed Test terminated early with bed plugging -- apparently due to catalyst particulate (Al identified in feed and catalyst bed) After catalyst break-in, only slight deactivation over time mass balance TOS 11-22h 1.83 1.04 <0.01 0.825 <0.7 0.077 90.4% TOS 22-35h 1.74 1.49 <0.01 0.838 <0.7 0.074 82.1% TOS 35-46 1.68 1.03 <0.01 0.851 <0.7 0.073 92.6% TOS 46-58 1.66 0.88 <0.01 0.848 <0.7 0.071 87.8% TOS 59-64 1.60 0.83 <0.01 0.858 <0.7 -- --
density Processing Results -- Red Mud Catalyzed feedstock Product sample H/C O TAN density moist H 2 g/g mass bal. TOS 19-31h 1.91 1.16 <0.01 0.800 <0.7 0.074 98.9% TOS 105-115h 1.85 1.00 <0.01 0.817 <0.7 0.071 106.0% TOS 164-176 1.83 1.21 <0.01 0.819 <0.7 0.067 102.7% TOS 236-248 1.82 1.13 <0.01 0.821 <0.7 0.073 103.2% TOS 297-307 1.81 1.01 <0.01 0.823 <0.7 0.070 104.5% Increase in LHSV had little effect After catalyst break-in, only slight deactivation over time
Processing Results -- Red Mud Catalyzed feedstock Mass oil yield trends higher throughout
Processing Results -- Red Mud Catalyzed feedstock very slight shift in distillation range over time on stream ASTM D2887 -- wt% Fraction QCE949 (diesel) HT red mud 43-55h HT red mud 111-128h HT red mud 236-248h HT red mud 297-307h Gasoline (IBP-184 C) 8.9 52.5 50.4 49.7 49.5 Diesel (184-344 C) 81.5 40.8 40.7 40.1 39.9 Heavy oil (>344 C) 9.6 6.7 8.8 10.2 10.6 Jet A (153-256 C) 41.0 31.2 29.2 28.4 28.3
Comparison of Catalytic Hydrotreating Results feedstock stages temp TOS Product Analysis C h H/C O TAN density Bio-oil* 3 140-180-400 704 1.65 2.3 NA 0.86 ZSM-5 1 400 64 1.60 0.8 <0.07 0.86 Red mud** 1 400 307 1.82 1.0 <0.01 0.82 * cold filtered to 400 mesh: Olarte et al. Prepr Pap Am Chem Soc Div Energy Fuels 2013 58(2) 230 ** hot vapor filtered Catalytic pyrolysis bio-oil vs. Fast pyrolysis Single-stage hydrotreating vs 3-stage Sulfided CoMo catalyst vs Ru and sulfided Ru and sulfided NiMo No evidence of catalyst fouling in 300 h time on stream with HVF cat. pyrol. bio-oil similar to 700 h with cold filtered bio-oil
2D NMR Aliphatic Region catalytic pyrolysis bio-oil ZSM-5 Red Mud HT bio-oil
2D NMR Aromatic Region catalytic pyrolysis bio-oil ZSM-5 Red Mud HT bio-oil
Summary of Results Improved bio-oil product by catalytic pyrolysis facilitates upgrading by catalytic hydrotreating More thermally stable bio-oil eliminates stabilization HT steps Reduced oxygen content means lower hydrogen requirement which is tempered by more aromatic hydrogenation Phase separation allows simple removal of light oxygenates which contributes to the first two bullets and water removal reduces hydrotreater reactor size requirement No evidence of catalyst fouling in 300 h time-on-stream with HVF in situ catalytic pyrolysis bio-oil Nearly complete deoxygenation is accomplished at severe processing conditions with sulfided catalyst High yield of hydrotreated bio-oil product with moderate hydrogen consumption
Acknowledgements PNNL U.S. Department of Energy Bioenergy Technologies Office VTT TEKES Utah State University - U.S. Department of Energy Subcontract to PNNL