CO₂ Direct Air Capture (DAC)

Direct air capture (DAC) of carbon dioxide (CO₂) is a pivotal technology in the battle against rising CO₂ concentrations and climate change. Extracting CO₂ from the atmosphere is also crucial for the hydrogen economy, as important green hydrogen vector molecules for transportation require carbon sources that may not be readily available in favorable regions for hydrogen production with low electricity generation costs. DAC is therefore an important link in the process chain of methanol synthesis and subsequent further processing into dimethyl ether and sustainable aviation fuels.

By utilizing DAC in conjunction with hydrogen produced via electrolysis from renewable electricity, we can synthesis i.e. liquid methanol, which can be transported using existing harbor and shipping infrastructure. Moreover, carbon capture methods enable the achievement of negative CO₂ emissions by underground storing, a key component in reaching net-zero emission targets.

Our approach combines the appropriate absorption materials with optimal process conditions, such as temperature and humidity, alongside frameworks that include low-carbon electricity, heat sources, and CO₂ storage. This holistic strategy aims to enhance overall efficiency in CO₂ utilization and reduction. 

We offer:

• CO₂ adsorption material characterization
• Experimental CO₂ DAC Process Evaluation
• DAC Reactor and Process model development
• Assessment of techno-economics and ecologic impacts of DAC processes

Your benefits:

• Faster, lower-risk DAC development: You benefit from our end-to-end capabilities, from material characterization to reactor and process-model development, shortening timelines and reducing project risk.
• Reliable data and reproducible results: Our advanced equipment and controlled test conditions deliver trustworthy data for decision-making.
• Scalable, deployable solutions: We help translate your DAC technology from lab to field with our reactor design and manufacturing capabilities.
• Clear pathways to carbon neutrality: Tailor-made techno-economic and ecological insights from our assessments identify viable routes to integrate DAC with renewable power and the green hydrogen economy.

Our mixSorb device features versatile reactors available in 10 ml and 100 ml sizes to accommodate various experimental needs. With controlled air mass flow rates and inlet temperature range of 15 to 90°C and enables detailed evaluation of adsorbent performance through CO₂ breakthrough curve analysis. The instrument is capable of heating materials up to 400°C to assess performance and allows for custom heating profiles. The CO₂ capacity in temperature swing processes will be verified by mass spectrometer and FTIR analysis. With a vacuum pump the desorption process can be accelerated.

An evaporator and a water saturator enable the adjustment of the humidity, and the dew point respectively. Investigation of kinetic performance of adsorbents can be combined with of co-adsorption of different gaseous species. At Fraunhofer ISE, we leverage our expertise in zeolites, activated carbons, silica gels, and amine-based materials to deliver insightful research and development services.

Our Direct Air Capture Test Rig for Automated Process Evaluation (DAC-TRAP) is designed for automated temperature and vacuum swing process evaluation. It can supply air mass flow rates of up to 120 kg/h, which corresponds to approximately 1600 L/min with defined adjustment of the humidity, and the dew point respectively. The system supports multiple reactors and offers the possibility to integrate vacuum for efficient CO₂ desorption, enabling a sequenced operation of adsorption and desorption. Our focus is on how to improve process efficiency through and the perfect timing of and the combination of process steps. Additionally, we aim to explore strategies for enhancing the drying steps.

Our approach is utilizing advanced Computational Fluid Dynamics (CFD) simulations to enhance reactor design and optimize performance. We employ leading simulation software such as Aspen, MATLAB, and Ansys to accurately model the processes involved in CO₂ adsorption.

Our research focuses on developing kinetic, equilibrium, and heat of adsorption models to better understand the behavior of various adsorbents. We determine sorption selectivity by using laboratory data to fit isotherm models, ensuring that our simulations reflect real-world performance accurately. Additionally, we apply a Sequential Design of Experiments approach, allowing us to systematically evaluate the effects of different variables on the adsorption process.