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DESCRIPTIONChemists and Chemical Engineers Make the World a Better Place through Modern Developments in Heterogeneous Catalysis. Presented by S ANJAY P ATEL. Department of Chemical Engineering Institute of Technology, Nirma University. Content. Chemistry & Chemical Engineering - PowerPoint PPT Presentation
Department of Chemical EngineeringInstitute of Technology, Nirma UniversityChemists and Chemical Engineers Make the World a Better Place through Modern Developments in Heterogeneous CatalysisPresented bySANJAY PATEL
Chemistry & Chemical Engineering
History of Catalysis
Recent trends in Catalysis
Future trends in Catalysis
LuxuryHousehold commoditiesGadgetsIndustrial ChemicalsAlternative FuelsEnvironmentPopulationHealthEnergy DemandResearchAll other Engg
catalysis ,lecture - 1(1-42);lecture-2 (43-50)
Chemistry and Chemical Engineering more Integrated to the SocietySociety:Cleaner and safer processesWell accepted and integrated processesIndustry:Speed-up processesEnergy and cost effective processesNew catalysts and catalytic processesNew technologiesAcademia:New innovationsDeeper knowledge and understanding of phenomenaControl of phenomena
Role of Catalysis in a National Economy24% of GDP from Products made using catalysts (Food, Fuels, Clothes, Polymers, Drug, Agro-chemicals)> 90 % of petro refining & petrochemicals processes use catalysts90 % of processes & 60 % of products in the chemical industry> 95% of pollution control technologiesCatalysis in the production/use of alternate fuels (NG,DME, H2, Fuel Cells, biofuels)
Why R&D in catalysis is important
For discovery/use of alternate sources of energy/fuels/raw material for chemical industryFor Pollution controlFor preparation of new materials (organic & inorganic-eg: Carbon Nanotubes)
Three Scales of Knowledge Application
Some Developments in Industrial catalysis-11900- 1920sIndustrial Process Catalyst1900s: CO + 3H2 CH4 + H2O NiVegetable Oil + H2 butter/margarine Ni1910s: Coal Liquefaction NiN2 + 3H2 2NH3 Fe/KNH3 NO NO2 HNO3 Pt1920s: CO + 2H2 CH3OH (HP) (ZnCr)oxide Fischer-Tropsch synthesis Co,Fe SO2 SO3 H2SO4 V2O5
Industrial catalysis-21930s and 1940s1930s:Cat Cracking(fixed,Houdry) Mont.Clay C2H4 C2H4O AgC6H6 Maleic anhydride V2O51940s:Cat Cracking(fluid) amorph. SiAl alkylation (gasoline) HF/acid- clay Platforming(gasoline) Pt/Al2O3 C6H6 C6H12 Ni
Industrial catalysis-3 1950sC2H4 Polyethylene(Z-N) TiC2H4 Polyethylene(Phillips) Cr-SiO2 Polyprop &Polybutadiene(Z-N) TiSteam reforming Ni-K- Al2O3HDS, HDT of naphtha (Co-Mo)/Al2O3C10H8 Phthalic anhydride (V,Mo)oxideC6H6 C6H12 (Ni)C6H11OH C6H10O (Cu) C7H8+ H2 C6H6 +CH4 (Ni-SiAl)
Butene Maleic anhydride (V,P) oxidesC3H6 acrylonitrile(ammox) (BiMo)oxidesBimetallic reforming PtRe/Al2O3Metathesis(2C3 C2+C4) (W,Mo,Re)oxidesCatalytic cracking ZeolitesC2H4 vinyl acetate Pd/CuC2H4 vinyl chloride CuCl2O-Xylene Phthalic anhydride V2O5/TiO2Hydrocracking Ni-W/Al2O3CO+H2O H2+CO2 (HTS) Fe2O3/Cr2O3/MgO --do-- (LTS) CuO-ZnO- Al2O3
Industrial catalysis-4 1960s
Xylene Isom( for p-xylene) H-ZSM-5Methanol (low press) Cu-Zn/Al2O3Toluene to benzene and xylenes H-ZSM-5Catalytic dewaxing H-ZSM-5 Autoexhaust catalyst Pt-Pd-Rh on oxideHydroisomerisation Pt-zeoliteSCR of NO(NH3) V/ TiMTBE acidic ion exchange resinC7H8+C9H12 C6H6 +C8H10 Pt-MordeniteIndustrial catalysis-5 1970s
Ethyl benzene H-ZSM-5Methanol to gasoline H-ZSM-5Vinyl acetate PdImproved Coal liq NiCo sulfidesSyngas to diesel CoHDW of kerosene/diesel.GO/VGO Pt/ZeoliteMTBE cat dist ion exchange resinOxdn of methacrolein Mo-V-PN-C6 to benzene Pt-zeolite
Industrial catalysis-6 1980s
DMC from acetone Cu chlorideNH3 synthesis Ru/CPhenol to HQ and catechol TS-1Isom of butene-1(MTBE) H-FerrieriteAmmoximation of cyclohexanone TS-1 Isom of oxime to caprolactam TS-1Ultra deep HDS Co-Mo-AlOlefin polym Supp. metallocene catsEthane to acetic acid Multi component oxide Fuel cell catalysts Rh, Pt, ceria-zirconiaCr-free HT WGS catalysts Fe,Cu- based
Industrial catalysis-7 1990s
Industrial catalysis-8 2000+Solid catalysts for biodiesel - solid acids, Hydroisom catalystsCatalysts for carbon nanotubes - Fe (Ni)-Mo-SiO2
For Developed Catalysts MAINLY IMPROVEMENT IN PERFORMANCE by New Synthesis Methods & use of PROMOTERS
Green Chemistry is CatalysisPollution control (air and waste streams; stationary and mobile)Clean oxidation/halogenation processes using O2,H2O2 (C2H4O, C3H6O)Avoiding toxic chemicals in industry (HF,COCl2 etc)Fuel cells (H2 generation)
Catalysis in Nanotechnology Methods of Catalyst preparation are most suited for the preparation of nanomaterials Nano dimensions of catalystsCommon prep methodsCommon Characterization toolsCatalysis in the preparation of carbon nanotubesLatest Trends
Catalysis in the Chemical IndustryHydrogen Industry(coal,NH3,methanol, FT, hydrogenations/HDT,fuel cell)Natural gas processing (SR,ATR,WGS,POX)Petroleum refining (FCC, HDW,HDT,HCr,REF)Petrochemicals (monomers,bulk chemicals)Fine Chem. (pharma, agrochem, fragrance, textile,coating,surfactants,laundry etc)Environmental Catalysis (autoexhaust, deNOx, DOC)Latest Trends
HETEROGENEOUS CATALYSISAN INRODUCTION
- Diffusion of Reactants (Bulk to Film to Surface) - Adsorption - Surface Reaction - Desorption & Diffusion of Products Steps of Catalytic Reaction
Role of Chemists & Chemical EngineersTeam Work
Wet impregnation: Preparation of precursors (Cu & Zn-nitrates) solution Impregnation of precursors on alumina support Rotary vacuum evaporation Drying Calcination ReductionRotary vacuum evaporatorCatalysts Preparation
Wet ImpregnationCo-precipitationCatalysts Preparation
WI CuO/ZnO/Al2O3 CatalystCalcined
WI CuO/ZnO/Al2O3 CatalystCalcined
Spent Commercial Ni/Al2O3
Commercial Fe2O3 catalyst
Spent Commercial Fe2O3 catalyst
Pt, Pd and Rh on the Metox metallic substrates Pervoskite LATEST ResearchAuto-catalysts
Honey Comb Catalysts
CATALYST CHARACTERIZATIONBulk Physical PropertiesBulk Chemical PropertiesSurface Chemical PropertiesSurface Physical PropertiesCatalytic Performance
Bulk Chemical PropertiesElemental composition (of the final catalyst)XRD, electron microscopy (SEM,TEM)Thermal Analysis(DTA/TGA)NMR/IR/UV-Vis SpectrophotometerTPR/TPO/TPDEXAFS
Surface PropertiesXPS,Auger, SIMS (bulk & surface structure)Texture :Surface area- porosityCounting Active Sites: -Selective chemisorption (H2,CO,O2, NH3, Pyridine,CO2);Surface reaction (N2O)Spectra of adsorbed species (IR/EPR/ NMR / EXAFS etc)
Physical properties of catalystsBulk densityCrushing strength & attrition loss (comparative)Particle size distributionPorosimetry (micro(35 nm) and meso pores
CharacteristicsMethodsSurface area, pore volume & sizeN2 Adsorption-Desorption Surface area analyzer (BET and Langmuir)Pore size distributionBJH (Barret, Joyner and Halenda)Elemental composition of catalystsMetal Trace Analyzer / Atomic Absorption SpectroscopyPhases present & CrystallinityX-ray Powder DiffractionTG-DTA (for precursors)MorphologyScanning Electron MicroscopyCatalyst reducibilityTemperature Programmed ReductionDispersion, SA and particle size of active metalCO Chemisorption, TEMAcidic/Basic site strength NH3-TPD, CO2 TPDSurface & Bulk CompositionXPSCoke measurementThermo Gravimetric Analysis, TPO
BET Surface Area AnalyzerSurface area, Pore Volume, Pore Size & Pore size distributionMajor role of Chemical Engineer with Chemists for Hardware
Pore size distribution by BJH methodN2 adsorption/desorption Isotherm P2CZCeA Surface Area and Pore size Distribution Barret, Joyner, and Halenda (BJH) P3CZAP2CZCeAP2CZCeA Cu/Zn/Ce/Al:30/20/10/40P3CZA Cu/Zn/Al:30/20/50
Chemisorption AnalyzerDispersion, Metal Surface area and Metal Particle size; TPR, TPO, TPD
TGA/DTA AnalyzersCoke measurement & TPO
Reactions involved in SRM processCH3OH + H2O CO2 + 3H2 CO2 + H2 CO + H2O CH3OH 2H2 + CO CH3OH + (1-p)H2O +0.5pO2 CO2 + (3-p)H2 H0 = (49.5 - 242*p) kJ mol-1
CH3OH + 0.75H2O + 0.125O2 CO2 + 2.75H2 H0 = -10 kJ mol-1 H300 oC = 0 kJ mol-1
CH3OH + 0.5H2O + 0.25O2 CO2 + 2.5H2 H0 = -71.4 kJ mol-1 CH3OH + 0H2O + 0.5O2 CO2 + 2H2 H0 = -192 kJ mol-1
CH3OH + 1.5O2 CO2 + 2H2O H0 = -727 kJ mol-1 Reactions involved in OSRM process
Catalyst Activity Testing Activity to be expressed as: - Rate constants from kinetics - Rates/weight - Rates/volume - Conversions at constant P,T and SV. - Temp required for a given conversion at constant partial & total pressures - Space velocity required for a given conversion at constant pressure and temp
Operating Conditions for SRM & OSRM
ParametersCatalyst mass, g1-3 Contact-time (W/F) kgcat s mol-13-15 Temperature, oC200-300S/M molar ratio 0-1.8 (SRM)S/O/M molar ratio1.5/0-0.5/1 (OSRM)Pressure, atm1
Schematic diagram of OSRM process
Schematic diagram of OSRM process
T=280 oC, W/F=11 kgcat s mol-1, S/O/M=1.5/0.15/1 & P=1 atm Characterization and Activities of ZnO & Ceria promoted Catalysts
Co-precipitationP4CZAP3CZAP1CZCeAP2CZCeAP3CZCeACu/Zn/AlCu/Zn/AlCu/Zn/Ce/AlCu/Zn/Ce/AlCu/Zn/Ce/AlComposition, wt%30/30/4030/20/5030/25/5/4030/20/10/4030/10/20/40BET SA, m2 g-19210696108101Pore volume, cm3 g-10.260.320.280.340.29Cu dispersion, %9.412.810.219.614.8Cu SA, m2 g-118.3188.8.131.529.3Cu particle size, 108801015269X, %60776910090H2 rate, mmol s-1 kgcat-1132180160244217CO formation, ppm9400340014009951240
At Lab Scale Activity at Kinetically Controlled Conditions
Scale-up &CommercializationMajor Role of Chemists & Chemical EngineersExamples of Steam Reformer & Ammonia Reactor
catalysis ,lecture - 1(1-42);lecture-2 (43-50)
catalysis ,lecture - 1(1-42);lecture-2 (43-50)
Big picture: Sustainable Development
Green Chemistry Is About... CostWasteMaterialsHazardRisk Energy
The drivers of green chemistry
The 12 Principles of Green Chemistry (1-6)
It is better to prevent waste than to treat or clean up waste after it has been created.
2. Atom Economy
Synthetic methods should be designed to maximise the incorporation of all materials used in the process into the final product.
3. Less Hazardous Chemical Synthesis
Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to people or the environment.
4. Designing Safer Chemicals
Chemical products should be designed to effect their desired function while minimising their toxicity.
5. Safer Solvents and Auxiliaries
The use of auxiliary substances (e.g., solvents or separation agents) should be made unnecessary whenever possible and innocuous when used.
6. Design for Energy Efficiency
Energy requirements of chemical processes should be recognised for their environmental and economic impacts and should be minimised. If possible, synthetic methods should be conducted at ambient temperature and pressure.
7 Use of Renewable FeedstocksA raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.
8 Reduce DerivativesUnnecessary derivatization (use of blocking groups, modification of physical/chemical processes) should be minimised or avoided if possible, because such steps require additional reagents and can generate waste.
10 Design for DegradationChemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment.
11 Real-time Analysis for Pollution PreventionAnalytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances.
12 Inherently Safer Chemistry for Accident PreventionThe 12 Principles of Green Chemistry (7-12)
Green Catalytic ProcessesAlternative feedstocks, reagents, solvents, products Enhanced process controlNew catalysts Greater integration of catalysis and reactor engineering:membrane reactors, microreactors, monolith technology, phenomena integration Increased use of natural gas and biomass as feedstock Photodecomposition of water into hydrogen and oxygenCatalysts for depolymerizing polymers for recycle of the monomers Improvements in fuel cell electrodes and their operation
Cleaner and greener Environment: Catalysis New directions for research driven by market, social & environmental needs: Catalysis for energy-friendly technologies and processes (primary methods) New advanced cleanup catalytic technologies (secondary methods)Catalytic processes and technologies for reducing the environmental impact of chemical and agro-industrial solid or liquid waste and improving the quality and reuse of water (secondary methods) Catalytic processes for a sustainable chemistry (green chemistry and engineering approach) Replacement of environmentally hazardous catalysts in existing processes
How to Decrease the Greenhouse Effect?New catalysts for high output fuel cells Electricity production via electrocatalytic oxidation of hydrocarbonsChemical energy of hydrocarbon is converted to electricityCatalysts and processes for solar energy conversion and hydrogenproductionCO2 or other greenhouse gases are not emitted into the atmosphere, First solar energy is converted into the chemical energy of synthesis gas (CO + H2) via the endothermic reaction of methane reformingStorage of the synthesis gasThe stored energy can be released via the reverse exothermal methanation reactionCO + 3H2 CH4 + H2OEfficiency from 43 to 70 %Catalysts are needed for these reactions!!!
Examples of Green Catalysis
Examples of Green Catalysis
The use of auxiliary substances (e.g. solvents,separation agents, etc.) should be minimizedExamples of Green Catalysis
Poly lactic acid (PLA) for plastics production
Examples of Green Catalysis
Examples of Green Catalysis
TiO2 A GREEN CATALYST: CLEAN ENVIRONMENTExamples of Green Catalysis
TiO2 - Photocatalysis3.12 eV (380 nm)
Microreactors FutureCatalytic processes Uniform channel structure, fractal catalyst supports Scale-up How microreactor is connected to the macroworld? Operating regimes Controlled periodic processing Programmable reactor Process control Miniaturized sensors and actuators Local feedback and programmable regimes Advanced structure, materials, process control Multiscale finely defined; locally targeted globally optimized
Monoliths (Structured) vs Pellets (Random)Does the configuration alone improve performance?
Micro Process Plant
High surface-to-volume area; enhanced mass and heat transfer;
high volumetric productivity;
Laminar flow conditions; low pressure drop
Some Advantages of Microreactors & Monoliths
Residence time distribution and extent of back mixing controlled precise reaction engineering
Low manufacturing, operating, and maintenance costs, and low power consumption
Minimal environmental hazards and increased safety due to small volume
Scaling-out or numbering-up instead of scaling-up
Some Potential ProblemsShort residence times require fast reactionsFast reactions require very active catalysts that are stable (The two most often do not go together)Catalyst deactivation and frequent reactor repacking or reactivationFouling and clogging of channelsLeaks between channelsMalfunctioning of distributorsReliability for long time on-streamStructural issues
So far there are only two major commercial uses of micro-channel systems (monoliths) Automotive catalytic convectors (major success) Selective catalytic reduction (NH3 SCR) of power plant NOx
Applications of the Process Utilizing Biomass StreamsAqueousBiomassStreamExtractionExtractionPEM Fuel CellSOFC
ICEGensetMicroturbineGensetHydrogenAPRFuel GasAPREnergyCropsProcess Hydrogen
CATALYSIS IN THE PRODUCTION OF FUTURE TRANSPORTATION FUELS
Biofuels Life Cycle
Technology for Green & Biofuels
Biomass Sources For BiofuelsLignoCellulose (Cellulose, Hemicellulose, Lignin)Starch SugarsLipid Glycerides (Vegetable Oils & Animal Fats)
Structures in Lignocellulose
Pathways to Renewable Transportation Fuels
Biomass GasifierPyrolysisHydrolysisSyngasBio OilsMethanol,Ethanol,FT( diesel,etc) Refine to Liquid FuelsFerment to ethanol,butanolAqueous phaseReformingHydrogenGasoline additivesVeg OilsAlgae OilsBiodiesel
Bioethanol Overview - GlobalCurrent bioethanol production in US is 12 billion gallons. Most cars on the road in US today can run on blends of up to 10% ethanol.US DOE has estimated that there is a potential to produce over 80 Billion gallons of bio-ethanol from cellulose and hemi-cellulose present in corn biomass in the 9 major US corn producing states. This equates to over 250 Million tons of bio-ethanol and >$160 Billion revenue.Iogens Demo plant producing cellulosic ethanol from wheat straw in Canada since 2004. DuPont-Danisco JV has started demonstration of cellulosic ethanol from corncobs since Jan., 2010 in USA.Brazil currently blends 25% ethanol in gasoline and bioethanol is produced directly from sugarcane. Brazilian flex cars are capable of running on just hydrated ethanol (E100), or just on a blend of gasoline with 20 to 25% anhydrous ethanol, or on any arbitrary combination of both fuels China uses 10% bioethanol in gasoline .
2nd Generation Bioethanol Technology Overview
Hydrolysis based Technology Players
CompanyLocationTechnology Present Status DuPont- DaniscoUSAFeed stock - Agri residue. Alkaline pretreatment , enzymatic hydrolysis + C5/C6 Co-fermentationPilot Plant startedIogen/ShellCanadaFeed stock Agri Biomass. Pretreatment steam explosion. Enzymatic hydrolysis & fermentation of C5/C6 sugarsDemo. Plant operating, since 2004. Commercial Plant expected to be commissioned in 2011. LignolCanadaFeed stock - wood, agribiomass. Organosolv pretreatment & sepn. Of high purity lignin. Enzymatic hydrolysis and fermentation of C5 & C6 sugars separatelyTechnology proven at Bench scale.Pilot Scale under Engineering design.
Enzymatic based Cellulosic Ethanol ProcessBiomassLigninSecond Generation Bioethanol
Gasification based Technology PlayersGasification based Technology Players
CompanyLocationTechnology Present Status COSKATAUSAFeed stock - Agri residue, pet coke, MSW.Gasification to syn-gas & direct fermentation to ethanol.Completed pilot scale optimization. INEOS BioUSAFeed stock - Agri residue, MSW. Conventional Gasification to syn-gas & its fermentation to ethanol.Process under study in pilot plant.
BiomassGasification based Cellulosic Ethanol Process GasifierBioreactorDistillation/dehydrationMicrobeEthanol 99.7 wt%Syn-gas4 - 6% ethanol
Transportation Fuels from Cellulosic Biomass (Pyrolysis Route)
Transportation Fuels from BiomassBIODIESELSFirst 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 Esters
Veg Oil + methanol FAME + glycerineCatalysts:Alkali catalysts( Na/K methoxides); CSTR; Large water, acid usage in product separation
Fuel Quality Problems in First 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 2nd Generation Biodiesel. Hydrocarbon Biodiesel Technology
Hydrocarbon Biodiesel consists of diesel-range hydrocarbons of high cetane numberDeoxygenation 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 RefineriesHydrotreat /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 infrastructure - Engine compatibility; Feedstock flexibility
Capital Costs : EIA Annual Energy Outlook 2006
Natural gas to Transportation Fuels : OptionsNatural Gas SyngasI. Syngas Methanol (DME) GasolineII. Syngas Fischer-Tropsch Syndiesel Syndiesel Can use existing infrastructureIII. Syngas H2 Fuel Cell driven cars: Stationary vs On-board supply options for HydrogenNatural Gas Electricity;MCFC and SOFC can generate electricity by direct internal reforming of NG at 650C;Ni/ Zr(La)Al2O4, loaded on anode
Catalysts for conversion of NG to Transportation FuelsI.Syngas PreparationHydrodesulphurisation(Co/Ni-Mo-alumina)Syngas generation(H2/ CO); 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. 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 )
Petroleum - vs- Syngas :: DieselProperty Petro- Syn- Boiling Range,oC 150-300 150-300Density at 15 C,kg/m3 820-845 780S, ppm vol 10 - 50 70CFPP, oC -15 -20Cloud point,oC -8(winter) -15
Due to lower S, N and aromatics, GTL diesel generates less SOx and particulate matter.
Power and fuels from Coal / PetCoke Gasification Texaco EECP Project
FEED:1235 TPD OF PetCokePC SG (75%)Power Plant 25%FT fuel(tail gas Power)55 MW Electricity; Steam.20 tpd diesel; 4 tpd naptha82 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 gasificationSR: 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 gasificationH2/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.
Hydrogen Production Costs(The Economist / IEA)
SOURCE USD / GJCoal / gas/ oil/ biodiesel 1-5NG + CO2 sequestration 8-10Coal + CO2 sequestration 10-13Biomass(SynGas route) 12-18Nuclear (Electrolysis) 15-20Wind (Electrolysis) 15-30Solar (Electrolysis) 25-50
Sugar Cane Juice to H2
AQUEOUS PHASE REFORMING
C6H12O6 +6H2O 12H2 +6CO2(APR)Pt-alumina catalysts, 200 oC1 kg of H2 ($3-4) from 7.5 kg Sugar Fuel Efficiency of H2 >> diesel/gasoline
H2 Production from Glycerin
Available from Veg oils(40-98% in H2O)C3H8O3 +3H2O 7H2 + 3CO2Ru Y2O3 catalysts; 600 oC1 kg H2 from 7 kg glycerine H2 production from Biomass is less economically viable than production of ethanol and biodiesel from biomass.
Catalytic Direct Methane Decomposition to H2 and Carbon Nanotubes
Catalytic Auto Thermal Reforming of Methanol, Ethanol, DME to HYDROGEN for FUEL CELL
Pure H2 Supply Compressed H2 Liquid H2 H2 HydrideH2 from Reformed liquid HCH2Fuel Methanol Ethanol DMEH2 Combustion EngineSimilar to Gasoline Internal Combustion Engine
Pure H2 Supply Compressed H2 Liquid H2 H2 HydridH2 from Reformed liquid HCH2Fuel Methanol Ethanol DMEPEM Fuel Cell
Pure H2 Supply Compressed H2 Liquid H2 H2 HydridH2 from Reformed liquid HCH2Fuel Methanol Ethanol DMEPEM Fuel CellH2 Production from Fossil & Renewable Sources
Catalysts for H2O and CO2 Photothermal SplittingUsing Sunlight 1. H2O H2 + 0.5 O22. CO2 CO +0.5 O2FT Synthsis: CO + H2 (CH2)n petrol/Diesel Sandias Sunlight To Petrol Project: Cobalt ferrite loses O atom at 1400o C; When cooled to 1100o C in presence of CO2 or H2O, it picks up O, catalyzing reactions 1 and 2; Solar absorber provides the energy. Challenge: Find a solid which loses / absorbs O from H2O / CO2 reversibly at a lower temp.
*Splitting H2O with visible light
Future Fuels: Catalysis Challenges
Meeting Specifications of Future Fuels Remove S,N, aromatics, Particulate MatterPower Generation - Lower CO2 Production in Catalytic Gasification - Lower CO2 and H2/CO ratio in Syngas generationFT Synthesis: Lower CH4 and CO2 ;Inhibit metal sintering; Increase attrition strength; Reactor designBiomass: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 ChallengesDirect Conversion of CH4 to methanol and C5+. Catalytic Water and CO2 splitting using solar energy
******************************** Clearly micro reactors offer a whole series of advantages such as: 1) high surface to volume ratios and, due to small dimensions enhanced mass and heat transfer coefficients by one to two orders of magnitude, 2) laminar flow conditions and low pressure drop but ability to make RTD narrow by introduction of another phase, 3) controllable RTD and back mixing, 4) high volumetric productivity, 5) low manufacturing and operating costs, 6) increased safety due to small amount of material, 7) scale up in parallel (scale out).*S18 The following question then arises. With all their perceived advantages, and the technologies available to manufacture micro reactors in silicon, in glass and in steel, or other metals, why arent they more widely used? The answer is that they require very fast reactions and active stable catalyst (usually these two do not go together). Most importantly micro reactors are, due to small dimensions, more prone to fouling and clogging, leaks between channels, and their reliability and life on stream is an unknown. All of these are potentially solvable problems on a case by case basis. However, the perceived risk factor is too large for them to replace existing installations. Most likely acceptance of micro-devices will occur in the consumer products, distributed power systems, highly energetic fast reactions, in-situ production of hazardous chemicals. Other applications will be slower.******************************