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Co2 conversion
1) Atmospheric CO2 levels have risen from 280 ppm pre-industrially to over 410 ppm currently due to emissions from fossil fuel combustion and respiration. Maximum safe levels are believed to be 450 ppm or less to avoid worst effects of global warming and ocean acidification. 2) The document discusses strategies for converting CO2 into useful products like dimethyl carbonate (DMC), formic acid and methanol. It outlines more sustainable routes for producing these chemicals directly from CO2 rather than traditional methods that rely on other carbon sources. 3) Specifically, it presents a method for continuously producing pure formic acid by hydrogenating supercritical CO2 with an immobilized catalyst and base, avoiding high
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Co2 conversion
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- 2. The carbon sourcein 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 indanger • 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 andopportunity 1) Rising anthropogenic CO2 levels Use CO2 as a renewable carbon source Catalysts Co-reactants products 2) Depletion of fossil fuel resources
- 5. CO2 conversion Industrialized technologies Urea Cyclic carbonate Salicylic acid Developing technologies Methanol Formic acid Dimethyl carbonates Strategiesfor CO2 conversion Aresta,M.,Dibenedetto,A.,Utilisation of CO2 as a chemical feedstock: opportunities and challenges,2007,37,2975-2992
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- 7. Conventional route • Toxicityof 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 ethylenecarbonate 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
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- 11. Conventional route Commonly formicacid 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 CO2as 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
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- 15. Conventional route • Itsindustrial 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 • Developmentof 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 liabilityinto 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)
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