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 sorption systems engineering group investigates various energy and process engineering applications focusing on sorption-based technologies. In sorption, fluids (sorptives) are attached to liquids (absorption) or solids (adsorption). On the one hand, this phenomenon can be used directly to separate fluids in process engineering. On the other hand, heat is released as a result of this attachment, which can be utilized in energy engineering. The occurring loading processes can be reversed by, e.g., introducing heat.

Currently, the scientific focus lies on researching adsorption phenomena as well as developing and optimizing the technical application. The adsorbents studied include zeolites, SWS ("Selective Water Sorbents"), silica gel, activated carbons, and MOFs (Metal-Organic Frameworks). The studied sorptives primarily include water, ethanol, methanol, carbon dioxide, oxygen, and nitrogen.

The wide range of applications for adsorption technology includes, among others, the exploitation of regenerative energies for heating, drying, cooling, and air-conditioning purposes, as well as for the production of drinking water or the separation of fluids. Energy-engineering adsorption applications include heat pumps, heat transformers, and thermal energy storage systems to provide heating and cooling. Process-engineering adsorption applications include adsorption columns for dehumidification, separation of CO2, or generally for gas separation.

In their research projects, the sorption systems engineering group uses experiments as well as modeling, simulation, and optimization tools to develop and analyze technical applications. Currently, a particular focus lies on the provision of cooling, heat transformation to higher temperatures, and direct capture of CO2 from ambient air (Direct Air Capture, DAC) by adsorption. The current projects are characterized by close cooperation with various industrial partners.

Further research objectives include gaining comprehensive knowledge of the caloric and thermodynamic properties of the adsorbents: This includes both adsorbents available on the market as well as new developments. For this purpose, the adsorbents are investigated in specially developed test rigs, and the results are compiled in substance databases and used for model validation.


Laboratory Facilities

Bulk density according to DIN EN ISO 60
Evaporation test bench to investigate the heat transfer during thin-film evaporation
Kinetic test bench to determine temperature induced ad- und desorption kinetic for closed-loop adsorption processes
Magnetic suspension balance to measure adsorption equilibria
Modular sorption test bench to investigate adsorption chillers, adsorption thermal energy storage units, adsorption heat pumps, and adsorption heat transformers

Current Projects

DAC-TALES: Direct Air Capture - Transdisciplinary Assessment Combining Labs, the Environment, the Economy, and Society
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
DyHySt: 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
KapSchicht: Capillary assisted vaporization of water for thermal heat pumps
Open Adsorption Systems: Experimental Investigation of Adsorber-Designs and Sorbents
Sorb-Zero: Sub-Zero Cooling @ Zero Emission, Waste-Heat-Driven Adsorption Chiller Below 0°C
Sorption-based air conditioning for battery-driven electric busses
TailorSorb: Tailored adsorbents for stationary adsorption thermal energy transformation