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.
