Transient and Equilibrium Measurement of Sorption of Gases on Zeolites

• Applicant: Professor Dr.-Ing. Reiner Staudt
• Subject Area: Technical Chemistry
• Term: from 2003 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5420435

This project is primarily dedicated to the measurement of the time dependence of gas adsorption on zeolite materials following a change of pressure in the surrounding atmosphere. Experiments are performed gravimetrically, i. e. by using a highly sensitive magnetic suspension balance (Rubotherm, Bochum). The influence of intracrystalline diffusion for the mass exchange process between the gas and the solid sorbent phase is investigated by varying size, amount and bed arrangements of the zeolite crystals and also by changing pressure steps in lengths and directions (i. e. performing ad- and desorption processes). Also the mode of activation of the sorbent material, its pre-treatment or history and the number of pressure cycles to which it had been exposed will be taken into account. The project will deliver to the consortium the phenomenological uptake data as Transport diffusivities obtained under transient conditions. Also gas adsorption equilibria, i. e. the adsorption isotherms (or adsorption isobars) will be determined. This information is necessary to calculate the so-called Darken factor correlating transport and self-diffusivities. Finally, calorimetric and dielectric measurements of selected gas-sorbent-systems will be done leading to valuable energetic characterization of the system and exhibiting internal molecular relaxation processes, which cannot be observed by gravimetric measurements.

• DFG Programme: Research Grants
• Participating Person: Professor Dr. Jürgen Keller