Coal to Desired Fuels and Chemicals

Maohong Fan

SER Professor in the Department of Chem. & Petroleum Eng.

UNIVERSITY OF WYOMING 2-4-2013 [email protected] Phone: (307) 766 5633

1 I’m dirty I’m sticky I’m smelly

Oil Coal Without me, life isn’t easy!

I’m picky I’m rusty I’m sneaky

Trona Iron ore Rare earth Maohong Fan’s Research Group UW’s Clean Coal Technology Development Map

CO + small amout of CH CO 2 4 H 2 IGCC Electric Dried coal impregnated Power Separation with catalysts Light tar separation (note: One of the Catalytic pyrolysis (into naphthalene, 1‐ objectives is to minimize mode in the same naphthaleneacetic Synthetic Feed gases: CO+ CH Urea 2 reactor production in acid, anthracene, ammonia limited O 4 2 pyrolyis and gasification phenol, diesel DME modes) Olefins High‐value Synthesis of H carbon based Char/coke methanol 2O Chemicals 1 materials st choice of feed gases: CO Synthesis conversion Gasoline 2 + H :CO≈2 + near zero CH F‐Tsynthesis Catalytic gasification (converting the CO & H 2 4 limited O2 2 nd nd mode in the same obtained with 2 choice Jet/Diesel 2 choice of feed gases: CO2 reactor CO2 of feed gases) + CH (natural gas) higher 4 alcohols limited O + H O 2 2 CO+CO 2 CO + zero H+ zero CH Cleaning & Catalytic CO coupling 2 4 Oxalic acid (converting the CO separating CO +CO2 obtained with st1 obtained with st1 choice choice of feed gases of feed gases) Ethylene Polyester glycol

CO2 Ethanol Three Sample Projects to Be Presented

 Catalytic Coal Pyrolysis and Gasification ◦ Na-Fe based  Syngas to liquids ◦ Ethylene glycol  Environmental management

◦ CO2 Sample Project 1- Catalytic Coal Gasification

 Why catalyst? ◦ Increase gasification or carbon conversion rate/kinetics ◦ Decrease gasification temperature  Improve energy efficiency  Increase life span of gasifier ◦ Change the composition of syngas  Obtain desired CO:H2 ratio  Decrease CH4 concentration in syngas Catalytic Coal Pyrolysis and Gasification Setup

7 Effect of Na Catalyst on PRB Coal Pyrolysis

 Mole ratios of different gas products With 4% Na from catalytic coal pyrolysis at 600 oC [coal heating rate: 10 oC /min; pyrolysis CO /CO o 2 time at 600 C: Raw coal H /CO 2 30min; flow rate of H2/CH4 N2 :15 ml/min]

0.00.51.01.52.02.53.03.5 Mole ratio

 Addition of Na2CO3 (as a catalyst) can increase ◦ H2/CH4 ratio by ~170% ◦ H2/CO ratio by ~115% Effect of Na Catalyst on PRB Coal Conversion (X) and Gasification Kinetics (k)

1 1

0.8 0.8

0.6 Raw coal 0.6 Coal + 5% Na catalyst

0.4 700 C 0.4 700 C 750 C 750 C 850 C 800 C 0.2 900 C 0.2 850 C

Fractional conversion, X conversion, Fractional 900 C Fractional conversion, X conversion, Fractional

0 0 0 100 200 300 400 500 600 700 0 50 100 150 200 Time, min Time, min -4.5  Complete conversion at 750 oC ◦ Only ~200 min needed with the use of Na -5 y = -0.7044x + 1.123 5 wt% Na catalyst R² = 0.9648 0 wt% Na -5.5 ◦ ~700 min needed without use of Na catalyst

-6

 Activation energy [determined by ln k y = -1.0758x + 4.1535 R² = 0.9841 lnk~(1/T) plot] -6.5 ◦ ~60 kJ/mol with catalyst ◦ ~100 kJ/mol without catalyst -7

-7.5 8.5 9 9.5 10 10.5 1/T * 10-4 (K-1) Effect of Composite Catalyst on CO Concentration in Syngas

 Test conditions ◦ Mass of DAF coal: 5 g ◦ H2O flow rate: 180 ml/min ◦ N2 flow rate: 4.1 ml/min ◦ #1:1%-Fe+3%-Na ◦ #2: 2%-Fe+2%-Na ◦ #3: 3%-Fe+1%-Na  Observations ◦ Increase in temperature → significant increase in CO Molar yield of CO per mole of ◦ Increase in Fe in composite carbon in the char vs. different catalyst → considerable loadings of Fe and temperatures decrease in CO

10 Effect of a Composite Catalyst’s Composition and Temperature on H2 Concentration in Syngas with Steam Gasification

Test conditions- Mass of coal: 5 g; #1: 1%-Fe+3%-Na; #2: 2%-Fe+2%-Na; #3: 1.1 1.2 1.3 3%-Fe+1%-Na: #4: 4%-Fe+0%-Na. 1.4

1.5

l 1.6

l o

m  Composite catalyst can take the advantage of two individual 900 catalysts and overcome their 850

T ( °C 800 4 challenges )

750 3 2  Molar yields of H per mole of ding 2 700 e loa 1 % F carbon

Molar yield of H2 per mole of ◦ 3% Fe loading leads to the increase in o carbon in the char vs. different H2 production by 35% at 700 C. loadings of Fe and temperatures

2015/8/19 Effect of Na Catalyst on Carbon Conversion with CO2 Gasification

 Test conditions ◦ Gasification Temperature: 700 oC ◦ Mass of DAF coal: 5 g ◦ CO2 flow rate: 180 ml/min ◦ N2 flow rate: 4.1 ml/min  Observations ◦ Addition of trona can significantly accelerate carbon conversion X (mole fraction) or coal gasification rate ◦ Gasifying the same amount of coal with catalyst needs  less time  a smaller gasifier

12 Effect of Catalyst on CO2 Gasification (continued)

 Pure CO could be obtained  1,200 min is needed for gasifying the coal without presence of catalyst.  Only 300 min is needed for gasifying the coal with the presence of catalyst.

Test conditions – Gasification temperature: 700 oC; mass of

coal: 5 g; CO2 flow rate: 180 ml/min; N2 flow rate: 4.1 ml/min.

2015/8/19 The Mechanism of PRB Coal Gasification with Fe Catalyst: Mössbauer spectroscopy data

100.0 100.0

99.5 98.0 Fe0

Fe3C 99.0 96.0 cementite 98.5 Fe O ,multiple 2 3 94.0 n+

Absorption (%) Absorption Fe

coordinations (%) Absorption 98.0 92.0 3% Fe in raw coal, 20oC 3% Fe coal after 97.5 pyrolysis at 800oC 90.0 -12 -8 -4 0 4 8 12 -12-8-404812 Velocity (mm/s) Velocity (mm/s)  During pyrolysis iron oxides are reduced to 0 metallic iron Fe , Fe3C and higher coordination n+ iron Fe 100.0  After steam introduction Fe C is oxidized to Fe0 Fe O 3 98.0 3 4 and Fe(O) np-Fe-ox  The catalytic mechanism on oxidized iron layer: 96.0 Fe0 Fe + H O → Fe(O) +H 2 2 94.0 Fen+

Fe(O) + C → C(O) + Fe (%) Absorption 92.0 C(O) → CO 3% Fe coal after pyrolysis at 800C + 10 min H O 3Fe(O)+H2O → Fe3O4 +H2 90.0 2 -12 -8 -4 0 4 8 12 Fe3O4 +CO→ 3Fe(O)+CO2 Velocity (mm/s) CO2 + C ↔2 CO Sample Project 2- Catalytically Coverting Syngas to Ethylene Glycol (EG) Syngas to ethylene glycol

2CO2CO + 2 +CH 2CH3CH3ONO2ONO (COOCH3)CH2 +2 ) 22NO+ 2NO MethylEthyl nitrite nitrite (EN) (MN) DimethylDiethyl Oxalate Oxalate (DMO) (DEO)

MethylEthyl nitrite nitrite 2NO2NO + + 0.5O 0.5O22 NN22OO33 toto NN22OO33 ++ 2CH2CH33CHOH2 OH 2CH 2CH3CH3ONO2ONO+ 2H+ 2H2O 2O EthyleneEthylene glycolglycol MethylEthyl nitrite nitrite (MN (EN))

(COOCH(COOCH3CH3)22)2++ 4H 4H2 2 (CH2OH)2 + 2CH3OHCH2OH DimethylDiethyl Oxalate Oxalate (DEO) (DMO) EthyleneEthylene glycol glycol (EG) (EG)

Disadvantages of methyl nitrite: Advantages of ethyl nitrite: • Highly flammable • Less flammable • Highly explosive • Non-explosive • Toxic • Less toxic • Being controlled in the US • Transportation allowed 16 1st Step of Syngas to EG: (CO +EN) → DEO

 UW DEO synthesis catalyst ◦ 0.1% DEO production catalyst prepared at UW can perform better than 1% that prepared with conventional method. ◦ Cost-effectiveness of UW catalyst is 9 times or 900% better than that of conventional ones. Integrated in-situ FTIR Based Set-up for Studying EG Reaction Mechanism In-Situ FTIR Observation of DEO Synthesis with and without Uses of a Promoter

Without DEO promoter

140 oC;1 atm; CO: EN;1.4 :1.

DEO With a promoter

CO (0.8 wt-%)

19 2nd Step of Syngas to EG: DMO→EG

• UW’s AC based catalysts achieve higher DMO conversion and EG + MG (methyl glycolate) selectivity in lower temperature range ( < 200 oC) • UW’s 20Cu-AS30-AC is the best catalyst – 100% CO conversion – 90% EG + MG 2015/8/19 Sample Project 3- New CO2 Capture Technologies

• Sorption based CO2 capture technology – Advantages • Easy in operation

• Applicable to gases with a wide range of CO2 concentrations

– Absorption: for pre-combustion CO2 capture

– Adsorption: for flue gas with low CO2 concentration – Shortcoming

• Slow CO2 desorption rates (especially for absorption based technology) → high desorption energy consumption

– the largest obstacle for reducing overall CO2 capture cost since about 70% of overall CCS capital is spent on CO2 desorption step • What to do? Using catalysis Catalytic CO2 Capture set-up Sample Project 3- Catalytic Based CO2 Capture Background

• Carbonates for CO2 capture – Mechanism (reversibility of the following reaction )

• Na2CO3 + H2O + CO2 ⇄ 2NaHCO3 2- - Or : CO3 + H2O + CO2 ↔ 2 HCO3 – Advantages

• Stoichiometric CO2-H2O ratio: almost equal to that in actual flue gas

• Na2CO3: inexpensive, stable, easily available – Disadvantage

• More difficult than amines based CO2 capture technology

in CO2 desorption or sorbent regeneration step 23 Catalytic Based CO2 Capture - Inorganic CO2 Desorption Rate Constants (k) with and without Uses of a Catalyst

Sample Temperature mkR2 • Test Conditions (°C) (min-1) 100 0.9 0.005 0.9992 – Mass of spent CO2 sorbent 120 1.0 0.02 1.0000 140 1.2 0.06 0.9991 (NaHCO3):50-100 mg Pure NaHCO3 – NaHCO /Catalyst (called NHF) 150 1.2 0.13 0.9991 3 160 1.2 0.29 0.9999 – N2 flow rate: 100 mL/min 100 0.7 0.19 0.9996 110 0.6 0.25 0.9994 • Observations 90 wt.% NHF 120 0.4 0.49 0.9995 130 0.4 0.89 0.9990 -1 – Rate constants [k (min )] increased 140 0.3 1.32 0.9975 significantly at the same temperature 100 0.6 0.20 0.9989 110 0.4 0.32 0.9989 due to use of the catalyst (e.g., kpure- -1 50 wt.% NHF 120 0.1 0.46 0.9994 NaHCO3 = 0.005 min , while k 90% = 0.19 min-1, k = 130 0.1 0.59 0.9997 wt.%NHF 50% wt.%NHF 140 0.1 0.84 0.9995 -1 -1 0.20 min , k 10% wt.%NHF = 0.06 min 100 0.5 0.06 0.9997 at 100 oC ) 110 0.5 0.13 0.9998 20 wt.% NHF 120 0.5 0.23 0.9998 • CO2 desorbs much faster due to use of catalyst 130 0.5 0.35 0.9998 • Reduce operating and capital costs 140 0.5 0.50 0.9998

24 Catalytic Based CO2 Capture - Inorganic Arrhenius Parameters A E Sample R2 A (min-1) (kJ/mol)

9 8 Pure NaHCO3 0.9988 9.66×10 ± 3.16×10 86 ± 2.5

90 wt.% NHF 0.9529 2.65×108 ± 2.43×107 64 ± 5.8

50 wt.% NHF 0.9493 4.86×105 ± 4.06×104 44 ± 3.5

20 wt.% NHF 0.9899 4.02×108 ± 1.72×107 69 ± 2.8

 Reduction in desorption activation energy also implies better adsorption

◦ ΔHR = EA,R – EA,-R a – catalyst b – 20 wt.% NHF

c – 50 wt.% NHF 25 d – 90 wt.% NHF Sample Project 4: Naphthalene synthesis Thanks to