Recording of single and multi-component isotherms using dynamic methods
For the characterization or the suitability testing of new materials, usually single component isotherms are recorded.
With the help of common adsorption models, such as the Ideal Adsorbed Solution (IAS) theory, the ideal separation behavior is then calculated. However, the IAS theory is only applicable to “ideal adsorption processes” and hence has limitations for materials such as zeolites, MOFs or carbon-based materials which mostly result in an over-evaluation of the material.
The alternative way for the experimental characterization of adsorbents is to include co-adsorption processes. However, this process can be very complicated since numerous parameters such as temperature, total pressure, and the composition of the gases, and thus the partial pressure, must be taken into account.
With the mixSorb S and the mixSorb SHP, it is now possible to record both single component isotherms up to a pressure of 8 bar (mix Sorb S) / 50 bar (mixSorb SHP) and multi-component isotherms on one instrument.
In the article of the recent issue 22 of our application magazine Particle World, different approaches are compared to prove the robustness of this method. Due to the relevance of the topic of CO2 adsorption for climate change, isotherms of CO2 and CH4 were recorded. They were measured using dynamic manometry, classical gravimetric adsorption and so-called step breakthroughs on a mixSorb SHP.
If you want to read more, you can download the article for free here: