Project Details
Projekt
Systematic investigation of the activation of zeolite X and correlation of cation distribution with adsorption properties
Subject Area
Chemical and Thermal Process Engineering
Term
since 2025
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 559086591
Zeolites are widely used as catalysts and adsorbents in industry. One important step of the synthesis route is the thermal activation. During activation the cations occupy their final position in the zeolite cage. The distribution of the cations influences the technically relevant adsorption properties, in particular adsorption capacity and heat. To date, there are no studies in which the influence of different activation conditions on crystallographic, adsorptive and energetic properties has been systematically investigated. The aim of the project is to mechanistically understand and model the cause-and-effect chain "process parameters of thermal activation" -> "cation distribution in the zeolite structure" -> "adsorption properties". This includes to develop a method for the correlation of cation distributions and adsorption properties of zeolites. Therefore, the activation of zeolite X is investigated with different experimental methods. In addition to Na-X and Ca-Na-X systems, other systems with divalent alkaline earth cations, e.g. Ba-Na-X and Sr-Na-X systems, are studied. In detail a combination of crystallographic, spectroscopic and volumetric-calorimetric measurements of zeolites activated under defined process conditions is proposed. In addition, in situ experiments (Raman, total scattering) under activation conditions will be combined with gas adsorption experiments. The high temporal resolution of the experiments is used to analyze not only equilibria but also the kinetics of the processes. Heuristic approaches are developed for modelling and evaluation of the measurement data, but also methods resulting from various models (e.g. based on Dubinin’s approach) are used.
DFG Programme
Research Grants
