Sorption Systems Engineering


Engelpracht, Mirko © Copyright: Lehrstuhl fuer Technische Thermodynamik der RWTH Aachen


Mirko Engelpracht

Group Leader Sorption Systems Engineering


+49 241 80 98176


  picture of adsorber module Copyright: © Chair of Technical Thermodynamics

The research group of sorption systems engineering studies the application of sorption phenomena in energy systems and process engineering systems. „Sorption“ is the physical or chemical bonding of a gaseous substance with a liquid (absorption) or a solid (adsorption). This bonding can be directly used for material separation in process engineering systems. Besides, heat is released during sorption, which can be used for heating purposes. The sorption process is reversible by heat input.

The group currently focuses on researching the adsorption phenomenon and developing technical applications, mainly using commercially available adsorbents like zeolite or silica gel and water as non-toxic sorptive with excellent thermal characteristics. Furthermore, sorbents such as selective water sorbents (SWS) and activated carbon are also investigated.

A wide range of applications is possible for sorption systems, including, e.g., the exploitation of renewable energy for cooling, heating, or air conditioning, as well as for water harvesting or material separation. In energy systems, adsorption systems can be used as heat pumps, heat transformers, chillers, and thermal energy storage units to provide heating or cooling. In process engineering systems, adsorption systems can be used as adsorption columns for dehumidification, separation of CO2, or gas separation.

The research work consists of conceptual design, including the design of components and development of concepts, modeling, simulation, and optimization, including validation of experimental models. Finally, experimental work is the main expertise of the research group, which includes prototyping and building up experimental setups. Our ongoing projects deal with the adsorption process, especially for providing cooling, transforming heat to higher temperatures, and capturing CO2 directly from the atmosphere (Direct Air Capture, DAC). Thereby, the close collaboration with industry partners characterizes our project work.

Further ambitions of our research are broadening the knowledge of caloric and thermodynamic properties of available and newly developed sorbents in combination with different sorptive materials. Therefore, self-made experimental setups are used to test the sorbents.


Laboratory Facilities

  • 'Small-scale' facilities to validate computational modeling
  • Modular test benches to investigate adsorption heat pumps, chillers, heat transformers, and thermal energy storage units
  • Test bench to determine adsorption and desorption kinetics by the large temperature jump method for closed adsorption processes
  • Test bench to characterize evaporator heat exchanger for closed adsorption processes
  • Thermogravimetric analyzer to measure adsorption equilibria

Current Projects

MoGaTEx: Model-based design of adsorption columns for gas separation based on small-scale experiments
SorpLib: Dynamic simulation of adsorption energy systems
SubSie-NoFrost: Sorption Steamers for Evaporation Temperatures Below 0 °C – Antifreeze by Additives

Completed Projects

2-bed Adsorption Heat Pump
Capillary assisted vaporization of water for thermal heat pumps
Dynamic hydrogen storage: Integrated model of electrolysis and gas conditioning
Experimental and Model-based Analysis of Adsorption Thermal Energy Storage
INTAS Study of solar assisted adsorption cooling unit using new adsorbent materials
Integrating cogeneration and thermal energy storage for an energy-efficient industrial batch process
Open Adsorption Systems: Experimental Investigation of Adsorber-Designs and Sorbents
Sorption-based air conditioning for battery-driven electric busses
TailorSorb: Tailored adsorbents for stationary adsorption thermal energy transformation