Multicomponent adsorption on activated carbons under supercritical conditions.

Area of Science:

• Chemical Engineering
• Materials Science
• Physical Chemistry

Background:

• Accurate modeling of gas adsorption on activated carbon is crucial for industrial applications.
• Existing models often struggle to predict binary mixture adsorption behavior, especially at high pressures.
• Understanding the distribution of adsorption sites and their potentials is key to improving adsorption models.

Purpose of the Study:

• To develop and validate a new model for predicting binary mixture adsorption on activated carbon (Norit R1).
• To characterize activated carbon using a distribution function of elements of adsorption volume (EAV) over solid-fluid potential.
• To enable reliable determination of partial adsorbed amounts for components in binary mixtures at high pressures.

Main Methods:

• Investigated adsorption of nitrogen-methane-carbon dioxide binary mixtures up to 15 MPa on Norit R1 activated carbon.
• Proposed a new model based on the distribution function of elements of adsorption volume (EAV).
• Evaluated EAV from pure component isotherms and used a combining rule for mixture adsorption calculations.

Main Results:

• The proposed model effectively describes experimental data for binary mixture adsorption.
• The model allows for the determination of adsorbed phase density and composition within each EAV.
• Reliably determined partial adsorbed amounts of components even when only total adsorption was measured.

Conclusions:

• The new model provides a robust framework for understanding and predicting high-pressure binary mixture adsorption on activated carbon.
• The EAV distribution function offers a powerful tool for characterizing adsorbent properties.
• The model's ability to determine partial amounts enhances its practical applicability in gas separation and storage.