Periodic Reporting for period 4 - CO2LIFE (BIOMIMETIC FIXATION OF CO2 AS SOURCE OF SALTS AND GLUCOSE)
Reporting period: 2022-07-01 to 2023-12-31
The continued increase in the atmospheric concentration of CO2 due to anthropogenic emissions is leading to significant changes in climate, with the industry accounting for one-third of all the energy used globally and for almost 40% of worldwide CO2 emissions. Fast actions are required to decrease the concentration of this greenhouse gas in the atmosphere, value that has currently reaching 400 ppm. Among the technological possibilities that are on the table to reduce CO2 emissions, carbon capture and storage into geological deposits is one of the main strategies that is being applied. However, the final objective of this strategy is to remove CO2 without considering the enormous potential of this molecule as a source of carbon for the production of valuable compounds. Nature has developed an effective and equilibrated mechanism to concentrate CO2 and fixate the inorganic carbon into organic material (e.g. glucose) by means of enzymatic action. Mimicking Nature and take advantage of millions of years of evolution should be considered as a basic starting point in the development of smart and highly effective processes. The project CO2LIFE presents the overall objective of developing a smart chemical process that converts carbon dioxide into valuable molecules using membrane technology in combination with enzymes and/or amino acids as mass transfer enhancers.
The objective of the CO2LIFE project is to develop a process to capture CO2 and convert it into valuable products by trying to mimic the Nature. The core of the process is based on two essential steps: i) CO2 conversion, in which the CO2 is converted into a valuable product; ii) product recovery, in which the converted CO2 coming from the previous stage is recovered as a pure compound.
During the project execution, several mass transfer enhancers have been studied in order to improve the CO2 transfer from the gas to the liquid: amino acids, the enzyme carbonic anhydrase (major enzyme in respiration in animals) and the enzyme RuBisCO (major enzyme in photosynthesis). Excellent results have shown that CO2 absorption was indeed enhanced, which is translated into smaller membrane contactors to achieve an efficient CO2 removal. In the absorption step, carbonate-based aqueous solutions showed a very good performance. In a second step, the liquid with reacted CO2 was sent to a membrane crystallizer where pure bicarbonate crystals were obtained. The overall process (absorption and crystallization) was optimized and patented, leading to the creation of the spin-off CO2MTECH. In addition, enzyme immobilization on the membrane surface was deeply evaluated, exploring new immobilization methods with application in CO2 capture and other fields. Life cycle assessments were constantly performed during the project execution, being used as a design tool in the decision making (selection of materials and solvents for membrane synthesis, optimal operation conditions, etc).
The CO2LIFE project has thus offered a novel CO2 capture and conversion process able to reduce CO2 emissions in an overall industrial context, as well as breakthrough advances in enymatic membranes and a clear vision on the impacts allocated to the technology.
During the project execution, several mass transfer enhancers have been studied in order to improve the CO2 transfer from the gas to the liquid: amino acids, the enzyme carbonic anhydrase (major enzyme in respiration in animals) and the enzyme RuBisCO (major enzyme in photosynthesis). Excellent results have shown that CO2 absorption was indeed enhanced, which is translated into smaller membrane contactors to achieve an efficient CO2 removal. In the absorption step, carbonate-based aqueous solutions showed a very good performance. In a second step, the liquid with reacted CO2 was sent to a membrane crystallizer where pure bicarbonate crystals were obtained. The overall process (absorption and crystallization) was optimized and patented, leading to the creation of the spin-off CO2MTECH. In addition, enzyme immobilization on the membrane surface was deeply evaluated, exploring new immobilization methods with application in CO2 capture and other fields. Life cycle assessments were constantly performed during the project execution, being used as a design tool in the decision making (selection of materials and solvents for membrane synthesis, optimal operation conditions, etc).
The CO2LIFE project has thus offered a novel CO2 capture and conversion process able to reduce CO2 emissions in an overall industrial context, as well as breakthrough advances in enymatic membranes and a clear vision on the impacts allocated to the technology.
The CO2LIFE project has led to a process that is beyond the current state of the art in the field of CO2 capture. The two main stages (conversion and recovery) have been optimized separately with very promising results, achieving optimisation of key variables and a complete understanding of the mass and heat transfer phenomena in the membrane contactors. Thanks to the project, the new technology has achieved a TRL 4. As result of the industrial interest of the developed process, the scaling up of the process is taking place and the spinoff CO2MTECH has been created.
Results regarding the development of novel methods for enzyme immobilization on the membrane surface have been published in peer-review scientific journals.
Results regarding the development of novel methods for enzyme immobilization on the membrane surface have been published in peer-review scientific journals.