2. The carbon source in the atmosphere
Atmospheric
concentration
• Pre-Industrial ~280 ppm
• Present - 410.57 ppm
by June 24 th 2018
Beneficial
• A greenhouse gas
• For photosynthesis
Emission
• Animals and plants respiration
• Fossil fuel combustion
http://www.esrl.noaa.gov/gmd/ccgg/trends/weekly.html (30.06.2018)
Characteristics
• Non toxic
• High thermodynamic stability
3. We are in danger
• Maximum allowable ≤ 450 ppm
Global warming
Climatic changes
Ocean Acidification
Miyama,T.,et al, Estimating allowable carbon emission for CO2 concentration stabilization using a GCM-based Earth system model,2009,36,1029
4. The problem and opportunity
1) Rising anthropogenic CO2 levels
Use CO2 as a renewable carbon source
Catalysts
Co-reactants
products
2) Depletion of fossil fuel resources
7. Conventional route
• Toxicity of phosgene
• Adverse environmental impacts
• Impurities in final product
• High energy demand
• Drawbacks -
Garcia,I.,et al,Environmental Assessment of DMC Production Comparison of Novel Electro-synthesis Route Utilizing CO2 with a Oxidative Carbonylation
Process,2016,4,2088−2097
Cat : AlCl3
• DMC is conventionally synthesized from phosgene–based route
CO(g) + Cl2(g) COCl2(g) (Phosgene)
COCl2(g) + 2 CH3OH(aq) CH3OCOOCH3(aq) (DMC) + 2 HCl(aq)
-5 to +30 ºC
8. Transesterification of ethylene carbonate
Souza, L. F. S.,et al,Production of DMC from CO2 via Indirect Route: Technical-Environmental Assessment and Analysis,2014,2,62−69
01
Capture from
concentrated
Sources
CO2 capture
& recovery
03
O
O O
+
Zeolite
1 bar
40°C
75%
yield
DMC + Ethylene
glycol
2 CH3OH
Reaction 2
RDS
02
CO2 +
O
O
O OMgO
39.5 bar
100°C 100%
yield
Reaction 1
04
Azeotrope - DMC- Methanol
Entrainer - Ethylene glycol
Azeotropic
Distillation
05
Obtain pure
DMC
Purification
9. Is It Sustainable ?
100% atom efficiency - No deleterious waste
High Efficiency
No use of Hazardous chemicals
Utilization of renewable raw materials
Souza, L. F. S,et al, Production of DMC from CO2 via Indirect Route: Technical-Environmental Assessment and Analysis, 2014, 2, 62−69
11. Conventional route
Commonly formic acid is synthesized by CO and H2O via methyl formate
• Need high amount of energy
The hydrolysis equilibrium is relatively unfavorable
• The CO used in the process is obtained from fossil resources
Artz,J,et al, Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment,2018,118,435-436
CH3OH(l) + CO(g) HCOOCH3(l)
Cat:(NaOMe)
80 °C,45 atm
HCOOCH3 (l) + H2O(l) HCOOH(aq) + CH3OH(aq)
12. CO2H2
Supercritical CO2 phase
CO2 + H2
CO2 HCOOH
CO2 + H2 HCOOH
HCOOH
P or T
Ionic Liquid Phase
Stabilizing base + Catalyst
Recycle
Mobile
phase
Stationary
phase
Continuous-flow hydrogenation of supercritical CO2
Wesselbaum,et al,Continuous-Flow Hydrogenation of Carbon Dioxide to Pure Formic Acid using an scCO2 with Immobilized Catalyst and Base.2012, 51, 8585−8588
13. • Using CO2 as the carbon source
• Need less energy -
Avoiding the generation of intermediates and the need for
tedious purifications
The use of supercritical CO2 as both reactant and extractive
phase affords continuous removal of product from the reactor,
thereby causing the reaction equilibrium to readjust
How it becomes sustainable ?
Artz,J,et al, Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment,2018,118,435-436
15. Conventional route
• Its industrial scale synthesis is based on synthesis gas and
catalysts under high pressure and elevated temperature
• Need high energy
• Major challenge is the removal of the excess heat to avoid
catalyst sintering
Artz,J,et al, Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment,2018,118,464
CuO/ZnO
50-250 bar
200-350 °C
CO(g) + 2 H2(g) CH3OH(l)
16. 1
Air
(400 ppm CO2 )
+ Pentaethyleneamine
(PEHA)
CO2 capture
2
In situ hydrogenation
H2 (50 bar)
1,4-dioxane
125-165°C
Overall reaction :CO2 (g) + 3H2(g)
Amine
Catalyst
CH3OH(aq) + H2O(l)
CO2 capture from air and conversion to methanol
Kothandaraman, J, et al, Conversion of CO2 from Air into Methanol Using a Polyamine and a Homogeneous Ruthenium Catalyst. 2016, 138, 778−781
CH3OH
Separation
3
CH3OH + H2O
• By simple distillation
79 % yield
17. Renewable
Energies
Sustainable methanol
Kothandaraman, J, et al, Conversion of CO2 from Air into Methanol Using a Polyamine and a Homogeneous Ruthenium Catalyst. 2016, 138, 778−781.
Green Electricity
Water electrolysis
H2O(l) H2(g) + ½ O2(g)
Methanol synthesis
CO2(g) + 3H2(g) CH3OH(aq)+ H2O(l)
Sustainable
Hydrogen
Combustion
CH3OH(l) + 3/2 O2(g) CO2g) + 2H2O(l)
18. Future perspectives
• Development of efficient catalysts
• Treepods – carbon scrubbing artificial trees
https://www.archdaily.com/118154/bostons-treepods-influx_studio(14.07.2018)
19. As
chemists
THINK !
Transform a
liability into an
asset with
long-term benefit
to our climate
$1 trillion
annual market
for at least 25
CO2 based
products
Carbon capture
and conversion
can reduce global
CO2 emissions by
10% by 2030
https://www.globalco2initiative.org(10.06.2018)