Liquid Fuel Desulfurization - TDA Research, Inc.

Diesel Fuel Desulfurization for use inFuel CellsAmbal Jayaraman, Gökhan O. Alptekin,John Monroe and Margarita DubovikFuel Cell Chemistry and Operation II240 th ACS National Meeting & ExpositionAugust 22 nd – 26 th , 2010Boston, MATDA Research Inc. Wheat Ridge, CO 80033 www.tda.com

Diesel Fuel APUs• Commercial long haul truckscould benefit from a fuel cellAPU to increase efficiency andcomply with noise and emissionregulations• The potential fuel savingsprovided by improved fuelefficiency could exceed $2billion per year• The power need for the truckbasedAPUs is 1-2 kWe• The low sulfur concentration ofULSD (< 15 ppmw) makes itpossible to use an expendabledesulfurizer cartridge• The cartridge can beregenerated off-vehicle toreduce complexityAPU SizeFuel Flow RateSulfur ContentReplacement Freq.Sorbent SizeSulfur CapacityHeavy Duty TruckDiesel1 kWe3.2 mL/min15 ppmw6 months1.2 L350 mL/mL2TDAR e s e a r c h

Sorbent Characteristics• TDA developed SulfaTrap TM -D1 an adsorbent fordesulfurization of logistics and transportation fuels• Sorbent characteristics:• High sulfur capacity• Regenerability– Small size and reduced replacement frequency• High removal efficiency– Reduce the sulfur concentration of the fuel to subppmlevels• Inertness– No undesirable side reactions– No change in fuel properties• Ease of handling and disposal– No toxicity, flammability, pyrophorocity3TDAR e s e a r c h

Bench-scale Test SetupSampling valveFuelPumpCeramic heater withReactor-1 insideReactor-2SulfurChemiluminescenceDetector (SCD)Liquid sampling4TDAR e s e a r c h

Ultra Low Sulfur DieselDesulfurization5TDAR e s e a r c h

Cummulative Sulfur Conc, ppmwSulfur Concn. inCollected Fuel (ppmw)Deep Desulfurization of ULSDT= 120 o C LHSV = 1.6 h -11412108T = 270 o C, P = 125 psig, LHSV = 4 h -1SulfaTrap TM -D1 (T = 270 o C; P = 125 psig)BP Road Diesel 14Conoco Diesel 11 -11 ppmw sulfur S1086Proprietary CarbonSelexs orbTDA-SulfaTrap-D1ppmw sulfurULSD Desulfurization @ 120 o C6442200 200 400 600 800 1000 1200mL Fuel Desulfurized/mL of Sorbent00 20 40 60 80 100 120Fuel Desulfurized mL/g• SulfaTrap TM -D1 sorbent can reduce the sulfur content of ULSD to lessthan 1 ppmw and showed significantly better performance at highertemperatures7TDAR e s e a r c h

ppmw sulfurTemperature, o CExtended Testing1412ULSD - 14.1 ppmw S (inlet) onSulfaTrap TM -D1(P = 125 psig)BP Road Diesel 14ppmw sulfur35030010250864cumulative average sulfur in effluentFuel Adsorption Temp.20015010025000 100 200 300 4000mL Fuel Desulfurized/mL of Sorbent• The extended testing of SulfaTrap TM -D1 provided ~ 400 mL of desulfurizedfuel per mL of Sorbent with < 3 ppmw S cumulative average sulfur leakage• SulfaTrap TM -D1 had increased capacity and removal efficiency at highertemperatureTDAR e s e a r c h

Sulfur Conc, ppm12108Adsorption TemperatureP=125 psig, Sulfur Content = 11 ppmw, LHSV= 4.0 h -1Fuel Temp = 208CFuel Temp = 245CFuel Temp = 265CConocoPhillipsDiesel11 ppmw S64200 200 400 600 800 1000Fuel Desulfurized mL/mL of sorbent• SulfaTrap TM -D1 had increased capacity and removal efficiency at higher temperature• SulfaTrap TM -D1 provided ~ 800 mL of desulfurized fuel per mL of Sorbent with < 2ppmw S cumulative average sulfur leakageTDAR e s e a r c h

Sulfur Conc, ppm12Activation TemperatureP=125 psig, Sulfur Content = 7 ppmw, LHSV= 4.0 h -1Fuel Temp = 265C - act- 250C - 7 ppmw S108Fuel Temp = 275C - act- 550C - 7 ppmw SFuel Temp = 275C - act- 400C - 7 ppmw S6ConocoPhillipsDiesel4200 200 400 600 800 1000 1200Fuel Desulfurized mL/mL of sorbent• SulfaTrap TM -D1 had increased capacity and removal efficiency at higher activationtemperatures• SulfaTrap TM -D1 provided ~ 650 mL of desulfurized fuel per mL of Sorbent with < 0.1ppmw S sulfur leakage at an activation temperature of 400 o CTDAR e s e a r c h

Cummulative Sulfur Conc, ppmwPerformance in Different ULSD FuelsP=125 psig, Sulfur Content = 11 ppmw, LHSV= 4.0 h -114SulfaTrap TM -D1 (T = 270 o C; P = 125 psig)1210864BP Diesel - 14.1 ppmw SConoco Diesel - 11 ppmw SDiamond Shamrock - 7 ppmw SShell Diesel - 5 ppmw S200 300 600 900 1200 1500mL Fuel Desulfurized/mL of Sorbent• SulfaTrap TM -D1 had increased capacity and removal efficiency with Conoco andDiamond Shamrock(Valero refineries) diesel fuels• Presence of oxygenates, PAHs and/or certain additives has a significant impact onfuel desulfurizationTDAR e s e a r c h

Jet Fuel Desulfurization12TDAR e s e a r c h

Sulfur Concentration, ppmwtotal sulfur (ppmw)Jet Fuel DesulfurizationJP-5 fuel – T ads = 120 o C,Sulfur = 50 – 1100 ppmw, LHSV= 1.6 h -1504030Low S JP5 (50 ppmw S)JP5 (500 ppmw S)JP5/Cu (1100 ppmw S)500400300JP-8 fuel – T ads = 120 – 200 o C,Sulfur = 430 ppmw S, LHSV = 1.6 h -1TDA- SulfaTrap TM - D1JP-8 ~ 430 ppmw S200 o C & 75 psig200C, 75 psig120C, ambient202001010000 5 10 15 20 25Fuel Desulfurized, mL/g00 4 8 12 16 20 24mL fuel desulfurized/g of sorbent• TDA’s SulfaTrap TM -D1 achieved very high sulfur adsorption capacities• Sorbent could desulfurize ~ 15 mL/g of low sulfur jet fuel and can be usedan expendable liquid phase sulfur polishing sorbent• SulfaTrap TM -D1 sorbent works much more effectively at 200 o C and 75 psig• In order to maintain fuel in the liquid state, the fuel is pressurized to 75psig at 200 o C during adsorptionTDAR e s e a r c h

Sulfur concn. (ppmw S)Options for Regeneration Gas201816Regens in 2%H 2 /HeCycle # 1 = 7.0 mL/gCycle # 2 = 3.6 mL/gCycle # 3 = 1.6 mL/gCycle #4-14 = 0.3-0.5 mL/gTDA SulfaTrap (1/16" pellets)Optimization of Regen Gas @ 400-450 o CCycling Data - JP-5 with 500 ppmw S141210864Regenerations inH2%H 2 Regens2 /HeCycle # 4-14Cycle# 4-14Air RegenerationsCycle# 27-67Regenerations in airCycle # 27-52Air RegenerationsRegenerationsfollowed byinH 2air Reduction& 2%H 2 /HeCycle# # 15- 15-26200 0.5 1 1.5 2 2.5 3mL Fuel Desulfurized/g of Sorbent• SulfaTrap TM -D1 sorbent can be regenerated by using hot air,reducing gas or an inert gasConfidential14TDAR e s e a r c h

Sulfur Conc, ppmwMultiple Cycles with Air Regeneration450400350300250JP8 Desulfurization Cycling ProfileFeed Sulfur Level = 440 ppmwCycles 1-4 @200ºC, 75 psigCycles 5-23 @ 240ºC, 125 psigCycles 24-26 @ 280ºC, 125 psigCycle #1Cycle #2Cycle #8Cycle #23Cycle #24200150Cycle #25Cycle #261005000 2 4 6 8 10 12 14mL fuel desulfurized/mL sorbent• SulfaTrap TM -D1 sorbent achieved higher capacities at evenhigher temperatures of 240 and 280 o C• Sorbent regenerations carried out in air at 425 o C15TDAR e s e a r c h

Breakthrough ProfilesCycle #1 Cycle #8Feed440 ppmw SFeed440 ppmw STDAR e s e a r c h

Straight-cut Diesel Fractions17TDAR e s e a r c h

Straight-cut Diesel Desulfurizationtotal sulfur (ppmw)T=120°C, Sulfur Content = 120 ppmw, LHSV= 0.8 h -15040Cycle #1#6Cycle #2#1Cycle #33020Cycle #4Cycle #6Cycle #7#7#3#4#2100TDA- SulfaTrap TM - D10 1 2 3 4 5mL fuel desulfurized/g of sorbent• TDA SulfaTrap TM -D1 provided good performance for desulfurization ofstraight-cut dieselTDAR e s e a r c h

Sulphur (ppm)Sulfur capacity (% wt. S)Demonstration with Straight Cut Diesel• TDA pursued a Phase IIIdemonstration opportunity withan oil field service company forstraight cut diesel desulfurization90807060Diesel Sulphur Adsorbent TrialSulfatrap - D3 (activated)0.050%0.040%Sulfur SpeciationBreakthrough at 10 ppmw STDA DataIOR Data504030201000 1000 2000 3000 4000 5000 6000Volume (ml)Run #: I1Run #: I2Run #: I3• Independent field assessments by IOR confirmed the performance of TDA’sSulfaTrap TM -D3 sorbent• 2 kg sorbent in a single reactorConfidential0.030%0.020%0.010%0.000%0 1 2 3 4 5 6 7 8 9 10Cycle #TDAR e s e a r c h

High Temperature CyclingT=240°C, P = 125 psig, Sulfur Content = 200 ppmw, LHSV= 0.7 h -1• TDA’s sorbent desulfurized about 9 mL of straight cut diesel fuel per mL ofsorbent over 3 cycles• More cycles are being carried out currently to establish the working capacity ofthe sorbent over 20 cyclesConfidential20TDAR e s e a r c h

Conclusions• SulfaTrap TM -D1 sorbent is highly effective for deepdesulfurization of diesel fuels such as ULSD and jetfuels for fuel cell applications• The sorbent is regenerable in air and/or reducing gasat 400 o C and maintains its performance over manycycles• The sorbent is successful for desulfurization of bothstraight-cut diesel fractions and jet fuels in aregenerable manner21TDAR e s e a r c h