Coal to Desired Fuels and Chemicals Maohong Fan SER Professor in - PowerPoint PPT Presentation

Coal to Desired Fuels and Chemicals Maohong Fan SER Professor in the Department of Chem. & Petroleum Eng. UNIVERSITY OF WYOMING 2-4-2013 mfan@uwyo.edu Phone: (307) 766 5633 1

I’m smelly I’m dirty I’m sticky Oil Oil Coal Coal Without me, life isn’t easy! I’m rusty I’m sneaky I’m picky Iron ore Iron ore Trona Trona Rare earth Rare earth

Maohong Fan’s Research Group

UW’s Clean Coal Technology Development Map CO 2 + small amout of CH 4 CO H 2 IGCC Electric Dried coal impregnated Power Separation Light tar separation with catalysts (note: One of the Catalytic pyrolysis (into naphthalene, 1 ‐ Synthetic objectives is to minimize mode in the same naphthaleneacetic Urea Feed gases: CO 2 + ammonia CH 4 production in reactor acid, anthracene, limited O 2 DME pyrolyis and gasification phenol, diesel Olefins modes) Synthesis of High ‐ value Char/coke methanol carbon based H 2 O Chemicals materials 1 st choice of feed gases: Gasoline Synthesis conversion CO 2 + F ‐ T synthesis H 2 :CO ≈ 2 + near zero CH 4 Catalytic gasification (converting the CO & H 2 limited O 2 obtained with 2 nd choice mode in the same Jet/Diesel 2 nd choice of feed gases: CO 2 CO 2 reactor of feed gases) higher + CH 4 (natural gas) alcohols limited O 2 + H 2 O CO+CO 2 CO + zero H 2 + zero CH 4 Catalytic CO coupling Cleaning & Oxalic acid (converting the CO separating CO + CO 2 obtained with 1 st choice obtained with 1 st of feed gases) choice of feed gases Ethylene Polyester glycol CO 2 Ethanol

Three Sample Projects to Be Presented  Catalytic Coal Pyrolysis and Gasification ◦ Na-Fe based  Syngas to liquids ◦ Ethylene glycol  Environmental management ◦ CO 2

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:H 2 ratio  Decrease CH 4 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 o C [coal heating rate: 10 o C /min; pyrolysis time at 600 o C: CO 2 /CO Raw coal H 2 /CO 30min; flow rate of H 2 /CH 4 N 2 :15 ml/min] 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Mole ratio  Addition of Na 2 CO 3 (as a catalyst) can increase ◦ H 2 /CH 4 ratio by ~170% ◦ H 2 /CO ratio by ~115%

Effect of Na Catalyst on PRB Coal Conversion (X) and Gasification Kinetics (k) 1 1 0.8 0.8 Fractional conversion, X Fractional conversion, X Raw coal 0.6 0.6 Coal + 5% Na catalyst 0.4 0.4 700 C 700 C 750 C 750 C 850 C 800 C 850 C 0.2 0.2 900 C 900 C 0 0 0 100 200 300 400 500 600 700 0 50 100 150 200 Time, min Time, min  Complete conversion at 750 o C -4.5 Only ~200 min needed with the use of Na ◦ 5 wt% Na -5 y = -0.7044x + 1.123 R² = 0.9648 catalyst 0 wt% Na -5.5 ~700 min needed without use of Na catalyst ◦  Activation energy [determined by ln k -6 lnk~(1/T) plot] y = -1.0758x + 4.1535 R² = 0.9841 -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 ◦ H 2 O flow rate: 180 ml/min ◦ N 2 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 ◦ Increase in Fe in composite Molar yield of CO per mole of catalyst → considerable carbon in the char vs. different decrease in CO loadings of Fe and temperatures 10

Effect of a Composite Catalyst’s Composition and Temperature on H 2 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 3%-Fe+1%-Na: #4: 4%-Fe+0%-Na. 1.2 1.3 1.4 1.5 C 1.6 l o m /  Composite catalyst can take the 2 H l o m advantage of two individual catalysts and overcome their 900 850 challenges T(°C) 800 4 3  Molar yields of H 2 per mole of 750 2 g n i d a o 700 l e F carbon % 1 Molar yield of H 2 per mole of ◦ 3% Fe loading leads to the increase in carbon in the char vs. different H 2 production by 35% at 700 o C. loadings of Fe and temperatures 2015/8/19

Effect of Na Catalyst on Carbon Conversion with CO 2 Gasification  Test conditions Gasification Temperature: 700 ◦ o C Mass of DAF coal: 5 g ◦ CO 2 flow rate: 180 ml/min ◦ N 2 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 CO 2 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 o C; mass of coal: 5 g; CO 2 flow rate: 180 ml/min; N 2 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 Fe 0 98.0 Absorption (%) Absorption (%) Fe 3 C 99.0 96.0 cementite Fe 2 O 3 ,multiple 98.5 94.0 Fe n+ coordinations 98.0 92.0 3% Fe coal after 3% Fe in raw coal, 20 o C pyrolysis at 800 o C 97.5 90.0 -12 -8 -4 0 4 8 12 -12 -8 -4 0 4 8 12 Velocity (mm/s) Velocity (mm/s) During pyrolysis iron oxides are reduced to  metallic iron Fe 0 , Fe 3 C and higher coordination iron Fe n+ 100.0 After steam introduction Fe 3 C is oxidized to Fe 0 Fe 3 O 4  98.0 and Fe(O) np-Fe-ox Absorption (%) The catalytic mechanism on oxidized iron layer:  96.0 Fe 0 Fe + H 2 O → Fe(O) +H 2 94.0 Fe(O) + C → C(O) + Fe Fe n+ C(O) → CO 92.0 3% Fe coal after pyrolysis 3Fe(O)+H 2 O → Fe 3 O 4 +H 2 at 800C + 10 min H 2 O 90.0 Fe 3 O 4 +CO → 3Fe(O)+CO 2 -12 -8 -4 0 4 8 12 Velocity (mm/s) CO 2 + C ↔ 2 CO

Sample Project 2- Catalytically Coverting Syngas to Ethylene Glycol (EG)

Syngas to ethylene glycol 2CO + 2CH 3 CH 2 ONO 2CO + 2CH 3 ONO (COOCH 3 CH 2 ) 2 + 2NO (COOCH 3 ) 2 + 2NO Methyl nitrite (MN) Ethyl nitrite (EN) Dimethyl Oxalate (DMO) Diethyl Oxalate (DEO) Methyl nitrite Ethyl nitrite 2NO + 0.5O 2 2NO + 0.5O 2 N 2 O 3 N 2 O 3 to to Ethylene glycol N 2 O 3 + 2CH 3 CH 2 OH N 2 O 3 + 2CH 3 OH 2CH 3 CH 2 ONO + 2H 2 O 2CH 3 ONO + 2H 2 O Ethylene glycol Methyl nitrite (MN ) Ethyl nitrite (EN ) (COOCH 3 CH 2 ) 2 + 4H 2 (COOCH 3 ) 2 + 4H 2 (CH 2 OH) 2 + 2CH 3 CH 2 OH (CH 2 OH) 2 + 2CH 3 OH Diethyl Oxalate (DEO) Dimethyl Oxalate (DMO) Ethylene glycol (EG) Ethylene glycol (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

1 st 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 EN Without promoter DEO CO 140 o C;1 atm; CO: EN;1.4 :1. EN With a DEO promoter (0.8 wt-%) CO 19

2 nd 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 o C) UW’s 20Cu-AS30-AC • is the best catalyst – 100% CO conversion – 90% EG + MG 2015/8/19

Sample Project 3- New CO 2 Capture Technologies • Sorption based CO 2 capture technology – Advantages • Easy in operation • Applicable to gases with a wide range of CO 2 concentrations – Absorption: for pre-combustion CO 2 capture – Adsorption: for flue gas with low CO 2 concentration – Shortcoming • Slow CO 2 desorption rates (especially for absorption based technology) → high desorption energy consumption – the largest obstacle for reducing overall CO 2 capture cost since about 70% of overall CCS capital is spent on CO 2 desorption step • What to do? Using catalysis

Catalytic CO 2 Capture set-up

Sample Project 3- Catalytic Based CO 2 Capture Background • Carbonates for CO 2 capture – Mechanism (reversibility of the following reaction ) • Na 2 CO 3 + H 2 O + CO 2 ⇄ 2NaHCO 3 2- + H 2 O + CO 2 ↔ 2 HCO 3 Or : CO 3 - – Advantages • Stoichiometric CO 2 -H 2 O ratio: almost equal to that in actual flue gas • Na 2 CO 3 : inexpensive, stable, easily available – Disadvantage • More difficult than amines based CO 2 capture technology in CO 2 desorption or sorbent regeneration step 23