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HYDROGEN

Water + energy hydrogen + oxygen

Hydrogen + oxygen water + energy

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Hydrogen is ~75% of the known universe

On earth, it’s not an energy source like oil or coal Only an energy carrier like electricity or gasoline — a form of energy, derived from a source, that can be moved around

The most versatile energy carrier - Can be made from any source and used for any service - Readily stored in large amounts Almost never found by itself; must be liberated - “Reform” HCs or CHs with heat and catalysts - “Electrolyze” water (split H2O with electricity) - Experimental methods: photolysis, plasma, microorganisms,…

1 kg of H2 contains same energy as 1 gallon of gasoline, which weighs 6.2 pounds

Why is hydrogen so important?

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All fuels produce hazardous gases, but…

Hydrogen is comparably or less so, but different:

Clear flame, not visible from a distance and no smoke

Hard to make explode; can’t explode in free air; burns first

22× less explosive power

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Where Does Hydrogen Come From?

95% of hydrogen is currently produced by steam reforming

Partial Oxidation

Steam Reforming

Electrolysis

Thermochemical

Fossil Fuels

Water

Biomass

currently most energy efficient

requires improvements

not cost effective

requires high temperatures

Gasification

Microbial

requiresimprovements

slow kinetics

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Sources of hydrogen

• Hydrogen is one of the most abundant element in the universe.

• It can be produced from various sources as 75% of the materials contains hydrogen atoms.

• Water is an important source for hydrogen production using electrolysis.

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Biological/fermentation

Acetate formation C6H12O6 + 2H2O ------- 2CH3COOH + 2CO2 +4H2 Butyrate formation C6H12O6 -----CH3CH2CH2COOH + 2CO2 +2H2 Propionate formation C6H12O6 +2H2O --- 2CH3CH2COOH + 2H2Acetate + Ethanol production C6H12O6 + 2H2O → CH3CH2OH + CH3COOH + 2H2 + 2CO2

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Why Biomass to hydrogen?

• Biomass has the potential to produce hydrogen as a major fuel of the future.

• Biomass is renewable, consumes atmospheric CO2 during growth and is able to recycle CO2.

• Biomass is abundantly available in the form of residual crops and wastes

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H2 From Biomass

Biomass conversion technologies are

1. Fischer Troph ReactionThe Fischer–Tropsch process is a collection of chemical reactions that

converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons

2. Pyrolytic gasification3. Biological treatment of biomass4. Thermochemical H2 production

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Pathways From Biomass to H2Biomass

Thermochemical

Gasification High PressureAqueous

Pyrolysis

H2/CO CH4/CO2

CH3OH/CO2

H2/CO2

CH4/CO2

CH4 /CO2

H2/CO2H2/CH2/CO2

Bio-shift

Shift

Synthesis

Reforming shift

H2/CO2

Reforming shift

H2/CO2

Reforming shift

Severe

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Pathways from Biomass to H2Biomass

Biological

H2/CO2

Anaerobic Digestion

MetabolicProcessingFermentation

CH4/CO2

CH3CH2OH/CO2

H2/CO2H2/C

H2/CO2

Bio-shiftReforming

shift Pyrolysis

Reforming shift Photo-

biology

H2/O2

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Metabolic Processing of Biomass

H2 from biomass can also be produced by metabolic processing to split water via photosynthesis or to perform the shift reaction by photo biological organisms.

An artificial leaf is developed by Harvard Professor

?http://nocera.harvard.edu/DanielGNocera

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Direct Production of H2 From Biomass

• Gasification coupled with water-gas shift is the most widely practiced process route for biomass to H2.

• Thermal, steam and partial oxidation gasification technologies are under development around the world.

• Feedstocks include both residual crops and agricultural and forest residues.

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Oxidative Pyrolysis

By including O2 in the reaction separate supply of energy is not required

Biomass + O2 CO + H2 + CO2 + Energy

If air is used to supply O2 then N2 is also present.

Examples : GTI high pressure O2 blown gasifier, CFBD (TPS Termiska), High pressure slurry bed entrained flow gasifier (Texaco)

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Direct Solar Gasification

• Several investigators have examined the use of solar process heat for gasification or organic solid wastes to produce H2.

• Studies have shown favourable economic projections for solar gasification of carbonaceous materials such as agricultural waste to produce syn gas for producing H2.

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Biomass Derived Synthesis Gas (Syn Gas) ConversionSponge Iron and related processes

• Steam Iron processes is one of the oldest processes for producing H2 from syngas. (developed as early as 1910).Fe3O4 + 4CO 3Fe + 4CO2

3Fe + 4H2O Fe3O4 + 4H2

• Recently sponge Iron process has been extended to FeO3FeO + H2O H2 + Fe3O4

• Metal hydrides (e.g. LaNi5, and La Ni4.7 Al0.3) has also been investigated for continuous hydrogen recovery from biomass gasification mixtures lean mixtures.

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KEY PROCESS STEPS IN BIOMASS TO METHANOL AND H2

Methanol

Biomass

Pretreatment, drying, chipping

Gasifier

Gas Cleaning Reformer for higher hydrocarbons

Shift to adjust CO/H2 ratio

Methanol Production H2 Production

Gas Turbine/boiler

)

Steam Turbine

Purge gas

Hydrogen

Electricity

Electricity04/12/2013

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ABEAcetone Butanol Ethanol fermentation

Acetate formation C6H12O6 + 2H2O ------- 2CH3COOH + 2CO2 +4H2 Butyrate formation C6H12O6 -----CH3CH2CH2COOH + 2CO2 +2H2 Propionate formation C6H12O6 +2H2O --- 2CH3CH2COOH + 2H2Acetate + Ethanol production C6H12O6 + 2H2O → CH3CH2OH + CH3COOH + 2H2 + 2CO2

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Acetone–butanol–ethanol (ABE) fermentation is a process that uses bacterial fermentation to produce acetone, n-Butanol, and ethanol from starch.

The process is anaerobic (done in the absence of oxygen), similar to how yeast ferments sugars to produce ethanol for wine, beer, or fuel.

The process produces these solvents in a ratio of 3-6-1, or 3 parts acetone, 6 parts butanol and 1 part ethanol.

It usually uses a strain of bacteria from the Clostridia Class (Clostridium Family). Clostridium acetobutylicum is the most well-known strain, although Clostridium beijerinckii has also been used for this process with good results.

Background Information

Acetic AcidMW: 60.05bp: 117-118 °C

Butyric AcidMW: 88.11bp: 162 °C

ButanolMW: 74.12bp: 116 – 118 °C

Butanol is produced as a fermentation product by bacteria; known as, solventogenic Clostridia, when cultured on glucose-rich media containing acetic acid and butyric acid.-Recently, butanol has been gaining attention as a possible alternative to petroleum-based gasoline. Much effort is currently being made to reduce production costs to make butanol an economically viable option.

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Acetone is the organic compound with the formula OC(CH3)2.

This colorless, mobile, flammable liquid is the simplest example of the ketones.

Acetone is miscible with water, and virtually all organic solventsMore than 3 billion kilograms are produced annually, mainly as a precursor to polymers.

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Chemically, Acetone is produced by cumene process,benzene is alkylated with propene and the resulting cumene (isopropylbenzene) is oxidized to give phenol and acetone: C6H5CH(CH3)2 + O2 → C6H5OH + OC(CH3)2

Acetone is also produced by the direct oxidation of propene with a Pd(II)/Cu(II) catalysts,

Vegetable oil Plant with sugar(sugarcane)

Plant with starch(maize, potato, cassava)

Plant with ligno-cellulose

PURIFIED OIL

Synthetic catalysis

Gasification Hydrolysis

treatment

DehydrationEsterification

BIODIESEL BIOMETHANOLBIOETHANOL

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Fuel Type Specific Energy Density(MJ/kg)

Solid Fuels

Bagasse (Cane Stalks) 9.6        

Chaff (Seed Casings) 14.6        

Animal Dung/Manure 10- 15           

Dried plants (C6H10O5)n 10 – 16           

Wood fuel (C6H10O5)n 16 – 21           

Charcoal 30           

3.6MJ=1KWh

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Liquid Fuels

Fuel Specific Energy Density

Pyrolysis oil 17.5        

Methanol (CH3-OH) 19.9 – 22.7        Ethanol (CH3-CH2-OH) 23.4 – 26.8        

Ecalene 28.4        

Butanol(CH3-(CH2)3-OH) 36           Fat 37.656    Biodiesel 37.8        Sunflower oil (C18H32O2) 39.49      

Castor oil (C18H34O3)  39.5        

Olive oil (C18H34O2) 39.25 - 39.82      

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Gaseous FuelsFuel Specific Energy Density

Methane (CH4) 55 – 55.7        

Hydrogen (H2) 120 – 142           Fossil Fuels (comparison)

Coal 29.3 – 33.5        

Crude Oil 41.868    

Gasoline 45 – 48.3        

Diesel 48.1        

Natural Gas 38 – 50           Ethane (CH3-CH3) 51.9        

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• http://www.syntecbiofuel.com/butanol.php

powermin.nic.in/whats_new/pdf/IIP

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