Decarbonization Avenue : C2V - CO2 to Value

C2V - CO2 to Value @ CLIMAX - Introduction


The C2V section provides an introduction to the CO2 to Value decarbonization avenue @ CLIMAX and provides a detaied guide to the CO2 to value domain.

C2V - CO2 to Value - Background

CO2 is the most prominent greenhouse gas driving climate change.

Dramatically reducing the amount of CO2 in the atmosphere is critical to control the climate change and global warming challenges.

While a range of avenues and solutions are being pursued to reduce or eliminate CO2 emissions from diverse processes and activities, a parallel effort is exploring how to capture the current CO2 emissions, and what to do with the captured CO2.

Converting CO2 into useful products, thus deriving value while remediating CO2 emissions appears to be an attractive decarbonization avenue.

Current uses of CO2

While these days CO2 is viewed mainly as a pollutant and a greenhouse gas, CO2 has been used for a variety of end uses, in a variety of industries for many decades.

Some of the more well known uses of CO2 include its use as:

Beyond these, CO2 is being used in at least a dozen more uses even today. Some of these uses release the CO2 into the atmosphere - the fizz in our benerages, for instance. But even otherwise, all these end uses together will still form only a very small portion of the total CO2 emissions worldwide.

CO2 to value - decarbonization potential

With serious efforts ongoing around the world for capture of CO2 emissions, a parallel challenge is cropping with: What can we do with the captured CO2 emissons.

About 35 billion tons of anthropogenic CO2 are being emitted every year. Some estimates suggest that we may have to capture as much as 10 billion tons of CO2 per year from the atmosphere within the next couple of decades.

Storing such humungous amounts of CO2 poses its own challenges. If we wish to utilize CO2 in some way in order to sequester it or at least to reduce the net overall emissions, current applications can utilize only a small portion of the total emissions.

This is where the concept of C2V or CO2 to Value enters the picture. How about converting CO2 into products that are used in very large quantities? Such as:

Annually, the world produces about 30 billion tons of concrete. over 2 billion tons of chemicals, about 5 billion tons of food (human food alone) and over 4 billion tons of oil. CO2 can be used as a component to produce all of the above. 

This potential for CO2 to be used to make products that have very large markets worldwide has attracted the attention a whole lot of stakeholders - researchers, investors, corporates and the government. Some estimates suggest that these pathways could enable utilization of up to 6 billion tons of CO2 emissions per year by 2030.

Within just the last 3 years (starting about 2018), there has been an explosion of research and innovation efforts in the CO2 to Value domain.

Broadly, the research and commercalization trends in CO2 to Value are as follows:

CO2 has a fairly low amount of thermodynamic energy content, though not the lowest. It can thus react with both compounds that have energy content lower than itself or with those that are higher.

Examples of the former (reactions with compounds with lower energy) are its reactions to produce inorganic carbonates. Examples of the latter are its reactions with Hydrogen to produce hydrocarbon fuels.

Reactions of CO2 with compounds with lower energy will not reqire significant energy inputs. For instamce, CO2 can mix with water without much energy inputs to form weak bicarbonates. But significant energy would be needed, along with effective catalysts, to perform reactions between CO2 and hydrogen

Thus, for the list above, only for CO2 to building materials pathway, the energy requirements will be low and relevant reactions can proceed under normal temperature and pressure with little energy inputs. For most other pathways, efficient catalysts and high temperature and pressure, optimal catalysts, would be needed for the reactions.

Significant advances in the green hydrogen ecosystem gas given a further boost to the CO2 to value domain. It has opened up a new genre, called the Power to X.

Power to X - an important dimension of C2V

In the last decade, both solar and wind power installations the world over have grown at a dramatic pace, resulting in a reasonable amout of green electricity production at economical costs. But most of the industrial processes and our transport run on liquid and solid fuels for heating, combustion and propulsion.

Is there some way the green electricity can be converted to low-carbon liquid or solid fuels? Or to low carbon chemicals, food or other materials?

A bit of thinking will lead you to the answer: It is possible because green electricity can be used to produce zero carbon hydrogen through electrolysis of water. The hydrogen can be combined with CO2 captured from emissions, and through a electrochemical reaction or through microbal pathways (both powered once again by renewable power), it can produce green chemicals, green fuels and energy low carbon food and proteins.

CO2 to value - summary of products & processes 

The following table summarizes the key trends in C2V

C2V Parameter Details
End product
  • Fuels
  • Chemicals
  • Food
  • Building materials
  • Others - biomass, carbonates...
Conversion  Process

Generic processes

  • Electrochemical
  • Thermochemical
  • Biochemical
  • Photochemical
  • Non-catalytic chemical reaction under ambient conditions

Specific processes involved

  • Gasification
  • Fermentation
  • Hydrogenation
  • Carbonation
Status of the processes Almost all the processes for the emerging products are in their very early or early stages of commercialization.


Value chain for C2V

C2V Stage 1: Sourcing of CO2

The value chain starts with the captured CO2 from a source of emission. In cases where biomass is considered as a proxy for CO2 capture, the value chain starts with the sourcing of biomass.

Key stakeholders for this stage include:

C2V Stage 2: Sourcing of other feedstock

The next stage of the value chain is the sourcing of other feedstock that would be used for value recovery from CO2. These feedstock could be:

Stakeholders for this stage include:

C2V Stage 3: Conversion process

The subsequent stage in the CO2 to value chain would be the processing of the feedstock. This part of the value chain can be quite diverse, and can comprise one or more of the following processes:

Depending on the end product, this stage could in turn have sub-stages, some of which could be happening in different locations. For instance, if the CO2 were to be converted to polyesters, the CO2 has to be first converted into alcohols (say. ethanol), which needs to undergo a further, distinct chemical process to be converted to polyesters. It is possible that the ethanol production and polyester production facilities are different from one another.

This stage comprises many stakeholders, including:

C2V Stage 4: Packaging & distribution

Depending on the end product, the processes in this stage of the value chain will vary. The stage could comprise one or more of the following:

Stakeholders for this stage include:

C2V Stage 5: End use

Once again depending on the product, the end use infrastructure and equipment could vary, and it can comprise of one or more of the following:

Stakeholders for this include:

C2V Stage 6: Use of the product, and partial or full emissions of the carbon

During the use phase of the product made from CO2, in some cases, the captured or converted CO2 could again be emitted into the atmosphere in some form. Prominent examples of this would be

Stakeholders for this stage include:

Some of the value chain stages noted above can be quite intricate and comprise multiple sub-stages.

Key topics in CO2 to value

The following comprise some of the key sub-themes and sub-topics for the C2V domain:

C2V - Industry-specific uses of CO2

CO2 has been of industrial value for quite some time in many applications. The emerging and future applications of CO2 will add to this already diverse basket of uses. The following table provides a comprehensive list of uses of CO2 - both current and emerging - categorised by industry sector. Current applications of CO2 are marked with a * .

Industry Uses
  • Jet fuel
  • Carbon fiber
  • In greenhouses for increaing yield *
  • CO2-based biochar
  • CO2-based soil fertility minerals
Animal rearing & livestock
  • Stunning animals before slaughter *
  • Animal feed
  • Low carbon or zero carbon building materials
  • Green concrete
Auto parts & ancillaries
  • CO2 based plastics for car components & interiors - polypropylene, polyurethane
  • Carbon fiber
  • Transport fuel
  • Aviation Jet Fuel
Building materials
  • Green concrete
  • Non-cement building materials
Chemicals & fertilizers
  • Recycled CO2 from hydrogen production stage used for urea production
  • Supercritical CO2 used for solvent extraction *
  • For making baking soda
  • To recover coal bed methane *
  • For blasting coal *
Consumer durables
  • Thermoplastics from CO2
Defense & security
  • Decentralized liquid hydrocarbon generation for remote regions
Fashion & lifestyle
  • CO2-based textile fabrics
  • CO2-based cosmetics & fragrances
  • For inflating life rafts & life jackets *
  • Urea production *
  • Enhanced CO2 capture for microalgae growth
  • Fish feed from CO2
Food & beverage production
  • CO2 to protein
  • CO2 to sugars
  • CO2 to animal food
  • Cryogenic & tumble freezers in food processing *
  • CO2 dry ice for food preservation *
  • Carbonation agent for beverages *
  • To control insects in sealed grain storages and ship holds, replacing harmful fumigants *
Food & beverage services
  • Fire extinguisher *
  • Dry ice *
  • Refrigerant *
Foundry & metal making
  • Shield gas for welding *
Furniture & home furnishing
  • Plastic furniture made from recycled CO2
Gas stations
  • Fire extinguisher *
Gems & jewelry
  • Diamonds from CO2
Home care & maintenance
  • Detergents made from recycled CO2
  • Rodent killing *
  • Liquid CO2 used as solvent for dry cleaning *
Hospitals & healthcare
  • Fire extinguisher *
  • Used for respiratory stimulation in hospitals *
HVAC systems
  • Refrigerant *
Metals & minerals
  • Cryogenic metal cleaning *
  • Coolant in foundries *
  • Bauxite residue carbonation * 
  • Stirring molten metal processes *
Oil & gas
  • Enhanced oil recovery *
  • Use of supercritical CO2 for fracturing for shale ga/oil recovery
  • Plastics production
  • Meat packing *
Plastics & rubber
  • Plastics production
  • Foaming rubber and plastics *
Power generation
  • Power to X
  • Use of supercritical CO2 as a working fluid for conventional thermal power plants as well as geothermal power plants
Rail transport
  • Feedstock for transport fuel
Road transport

Feedstock for:

  • Gasoline
  • Methanol
  • Ethanol
  • Methane
Solid waste management
  • Combining select industrial solid wastes with CO2 to make building materials
  • Feedstock to produce syngas that can be used in blast furnace
  • CO2 to sugar
Textiles & leather
  • Textile fibers from CO2
Warehousing & storage
  • Dry ice *
  • Refrigerant *
Wastewater treatment
  • Enhancing growth of microalgae for bioremediation
  • Use of CO2 as carbonic acid in wastewater treatment to control pH, in place of other chemicals*
  • Carbonation of bottled water *
Water transport
  • Methane
  • Methanol


C2V - Valuable web resources

Key organizations & networks