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CATALYSIS IN THE PRODUCTION OF FUTURE TRANSPORTATION FUELS. How long will Fossil Hydrocarbon fuels last ?. FUEL Reserve/Production Oil 40 years Natural Gas 65 years Coal / tar sands 200 years
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How long will Fossil Hydrocarbon fuels last ? FUELReserve/Production Oil 40 years Natural Gas 65 years Coal / tar sands 200 years Note:1. Increasing recent demand from India & China are not taken into account. 2.New reserves since 2004 are not taken into account. British Petroleum Statistical review of World Energy, June 2004. (www.bp.com/statisticalreview2004)
Role of Catalysis in a National Economy • 24% of GDP from Products made using catalysts(Food,Fuels,Clothes,Polymers,Drug,Agro-chemicals) • > 90 % of petro refining & petrochemicals processes use catalysts • 90 % of processes & 60 % of products in the chemical industry • > 95% of pollution control technologies • Catalysis in the production/use of alternate fuels (NG,DME,H2,Fuel Cells,biofuels…)
OUTLINE OF TALK • Catalysts for Natural Gas conversion to gasoline and diesel - Challenges • Catalysts for conversion of Coal to Transportation Fuels-Challenges • Catalysis in Hydrogen Production for Fuel Cells- Challenges • Catalysts for BiodieselProduction • Solar energy as future fuel-Catalysts for H2O and CO2 splitting .
Natural gas to Transportation Fuels : Options • Natural Gas Syngas • I. Syngas Methanol (DME) Gasoline • II. Syngas Fischer-Tropsch Syndiesel Syndiesel Can use existing infrastructure • III. Syngas H2 Fuel Cell – driven cars:Stationary vs On-board supply options for Hydrogen. • Natural Gas Electricity;MCFC and SOFC can generate electricity by direct internal reforming of NG at 650C;Ni/ Zr(La)Al2O4, loaded on anode; problem is alkali poisoning;fuel-to-electricity efficiency ~ 60%;thermal eff ~85%; 2 MW plants demonstrated;
Catalysts for conversion of NG to Transportation Fuels I.Syngas Preparation • Hydrodesulphurisation(Co/Ni-Mo-alumina) • Syngas generation(H2/ CO ~ 1); POX,steam, autothermal, “dry” reforming; Ni(SR),Ru(POX) – based catalysts; Pt metals for POX for FT. 2.Fischer Tropsch Synthesis: Co – Wax and mid dist; Fe - gasoline; Cu & K added. Cu increases mol wt of HC; spray dried ,~60 m size; Supported Co preferred due to its lower WGS activity & consequent lower loss of C as CO2. 3.Product Work up: Wax Conversion to diesel and gasoline. Mild Hydro-cracking/ Isom catalysts(Pt metal- acidic oxide support )
Petro- vs- Syn Diesel PropertyPetro-Syn- Boiling Range,oC 150-300 150-300 Density at 15 C,kg/m3 820-845 780 S, ppm vol 10 - 50 <1 Aromatics,% vol 30 <0.1 Cetane No >51 >70 CFPP, oC -15 -20 Cloud point,oC -8(winter) -15 Due to lower S, N and aromatics, GTL diesel generates less SOx and particulate matter. Oil & Gas(Eur Mag);2/2007;page 88
Power and fuels from Coal / PetCoke Gasification Texaco EECP Project: Topics Catalysis, 26 (2003)13 FEED:1235 TPD OF PetCoke PC SG (75%)Power Plant 25%FT fuel(tail gas Power) • 55 MW Electricity; Steam. • 20 tpd diesel; 4 tpd naptha • 82 tpd Wax(60 tpd diesel); 89 tpd S; • H2: CO = 0.67;Once-thru slurry(Fe) FT reactor; RR = 15 % at a refinery site.
Coal To Syngas To Fuel Cells Catalysis in Coal / PetCoke gasification • SR: C + H2O CO + H2 (+117 kJ/mol) Combust:2C+ O2 2CO (H = -243 kJ/mol) WGS :CO + H2O H2 + CO2 ( -42 kJ/mol) Methan: CO+3 H2 CH4 + H2O(- 205 kJ/mol) • Methanation can supply the heat for steam gasification and lower oxygen plant cost.K & Fe oxides lower temp of gasification • H2/CO ~0.6 in coal gasification;Good WGS is needed; • MCFC and SOFC can use H2,CO, & CH4 as fuel to generate electricity. • Low rank coals, Lignites gasify easier.
Biomass Sources For Biofuels • LignoCellulose ( cellulose, Hemicellulose, Lignin) • Starch • Sugars • Lipid Glycerides ( Vegetable Oils & Animal Fats)
COMPOSITION OF VEGETABLE OILS R’, R”, R’” = C12 to C20 groups Fatty acid triglyceride
Pathways to Renewable Transportation Fuels Biomass Methanol, Ethanol, FT( diesel,etc) Gasifier Syngas Veg Oils Algae Oils Biodiesel Pyrolysis Bio Oils Refine to Liquid Fuels Ferment to ethanol, butanol Gasoline additives Hydrolysis Aqueous phase Reforming Hydrogen
Transportation Fuels from Cellulosic Biomass(Pyrolysis Route)
Sugar Cane Juice to H2 AQUEOUS PHASE REFORMING • C6H12O6 +6H2O 12H2 +6CO2(APR) • Pt-alumina catalysts,200 C • 1 kg of H2 ($3-4)from 7.5 kg Sugar ($2.25 at $300/ton) • Fuel Efficiency of H2 >> diesel/gasoline Int.J.Hydrogen Energy,32(6)(2007)717
H2 Production from GlycerineEnergy & Fuels,19(2005)1761 • Available from Veg oils(40-98% in H2O) • C3H8O3 +3H2O7H2 + 3CO2 • Ru – Y2O3 catalysts; 600 C; • 1 kg H2 from 7 kg glycerine H2 production from Biomass is less economically viable than production of ethanol and biodiesel from biomass.
Transportation Fuels from BiomassBIODIESELS • First generation biodiesel Fatty Acid methyl esters (FAME); methyl esters of C16 and C18 acids. • Second generation Biodiesels “Hydrocarbon Biodiesels” ; C16 and C18 saturated, branched Hydrocarbons similar to those in petrodiesel; High cetane number (70 – 80). • Third Generation Biofuels From (hemi)Cellulose and agricultural waste; Enzyme technology for (hemi)Cellulose degradation and catalytic upgrading of products.
First Generation Biodiesels Fatty Acid Methyl EstersFirst Generation Technology • Veg Oil + methanol FAME + glycerine • Veg Oils: Soya,rape seed,palm, jatropha, karanjia,cotton seed etc; Algae oils. • High melting point of some FAME CFPP Problems: Me palmitate(30 C); Me stearate(39 C); Me oleate(-20 C); Linoleate(-35 C); Linolenate(-52 C); • Catalysts:Alkali catalysts( Na/K methoxides); CSTR;Large water, acid usage in product separation
Operational Problems in First Generation Technology • Non refined oils need pretreatment to remove water and Free Fatty Acids. Prior esterification needed. FFAs cause corrosion/ soap / emulsions. • Need to use SS vessels (alkali / acid) • Metal alcoholates sensitive to H2O. Presence of water consumes catalysts & creates emulsions. Major problems in the biodiesel - glycerol separation step.
Fuel Quality Problems inFirst Generation Technology • Lower glycerol purity; Not suitable for production of chemicals( propanediol, acrolein etc)without major purification;Salts and H2O to be removed from Glycerol. • Residual KOH in biodiesel creates excess ash content in the burned fuel/engine deposits/high abrasive wear on the pistons and cylinders.
Catalysts for 1st generation Biodiesel.Second Generation Technology for FAME • Solid acid catalysts • Feedstock flexibility • Glycerine > 98% • No use of water in product separation/ purification;No harmful effluents; • Fixed bed Reactor operation • Reaction time longer than base catalysts
Catalysts for 2nd Generation Biodiesel. “Hydrocarbon Biodiesel “Technology • “Hydrocarbon Biodiesel” consists of diesel-range hydrocarbons of high cetane number • Deoxygenation and hydroisomerization of Veg Oil at high H2 pressures and temp. • Catalysts:NiMo(for deoxyg), Pt-SAPO-11(for isom); H2 at high pressure needed;Yield from VO is lower;C3 credit. • Can be integrated with petro refinery operations;Greater Feedstock flexibility. • Suitable for getting PP < - 20 C (Jet Fuels). • 40000 tpy plant in Finland; 200K tpy in Singapore;100K tpy plant using soya in SA.
Convert Veg Oil to HC Diesel in Hydrotreaters in Oil Refineries • Hydrotreat /Crack mix of VO + HVGO(5-10%); S=0.35%;N(ppm)= 1614;KUOP = 12.1; density=0.91 g/cc);Conradson C = 0.15%; Sulfided NiMo/Si-Al Catalyst; ~350C,50 bar; LHSV = 5; Diesel yield ~ 75%wt. • Advantages over the Trans Esterificat Route - Product identical to Petrodiesel(esp.PP ) - Compatible with current refinery infrastruct - Engine compatibility;Feedstock flexibility (Appl.Cat.329(2007)120)
Hydrogen Production Costs(The Economist / IEA) SOURCEUSD / GJ Coal / gas/ oil/ biodiesel 1-5 NG + CO2 sequestration 8-10 Coal + CO2 sequestration 10-13 Biomass(SynGas route) 12-18 Nuclear (Electrolysis) 15-20 Wind (Electrolysis) 15-30 Solar (Electrolysis) 25-50 Note:Due to complications of H2 storage, distribution and dispensing compared to liquid hydrocarbon fuels, very little correlation between bulk hydrogen costs at a refinery and at the customer’s dispensing station.
Catalysts for H2O and CO2Photothermal SplittingUsing Sunlight 1. H2O H2 + 0.5 O2 2. CO2 CO +0.5 O2 • FT Synthsis:CO +H2 (CH2)npetrol/Diesel Sandia’s Sunlight To Petrol Project: Cobalt ferrite loses O atom at 1400o C; When cooled to 1100o C in presence of CO2 orH2O, it picks up O, catalyzing reactions 1 and 2; Solar absorber provides the energy. Challenge: Find a solid which loses / absorbs O from H2O / CO2reversibly at a lower temp.
Future Fuels:Catalysis Challenges • Meeting Specifications of Future Fuels Remove S,N, aromatics, Particulate Matter • Power Generation - Lower CO2 Production in Catalytic Gasification - Lower CO2 and H2/CO ratio in Syngas generation • FT Synthesis: Lower CH4 and CO2 ;Inhibit metal sintering; Increase attrition strength; Reactor design • Biomass:1.Cellulose to Ethanol ( enzymes) 2. Biomass gasification catalysts. Decentralized Production/ Use of H2 and Biofuels will avoid costs due to their storage and distribution. “Holy Grail “ Challenges • Direct Conversion of CH4 to methanol and C5+. • Catalytic Water and CO2 splitting using solar energy