The Climeworks CO2 capture technology is based on a cyclic adsorption / desorption process on a novel filter material (“sorbent”). During adsorption, atmospheric CO2 is chemically bound to the sorbent’s surface. Once the sorbent is saturated, the CO2 is driven off the sorbent by heating it to 100 °C, thereby delivering high-purity gaseous CO2. The CO2-free sorbent can be re-used for many adsorption/desorption cycles. The beauty of the process is the fact that around 90% of the energy demand can be supplied by low-temperature heat; the remaining energy is required in the form of electricity for pumping and control purposes.
The patent-pending technology has been developed in collaboration with the Professorship of Renewable Energy Carriers at ETH Zurich. The optimization of the sorbent and scale-up of the sorbent synthesis process is carried out in collaboration with the Swiss Laboratories for Materials Science and Technology (Empa).