Equilibrium adsorption of diethyl ketone on activated carbon in a supercritical CO2 environment: Measurements and thermodynamic modeling

• Published in: Journal of CO2 utilization 2024-06, Vol.84, p.102857, Article 102857
• Main Authors: Ushiki, Ikuo, Tahara, Yuto
• Format: Article
• Language: English
• Subjects: Activated carbon; Adsorption equilibria; Diethyl ketone (DEK); Dubinin–Astakhov (DA) equation; Supercritical CO2; Volatile organic compound (VOC)
• ISSN: 2212-9820; 2212-9839
• DOI: 10.1016/j.jcou.2024.102857

This study focuses on the equilibrium adsorption of diethyl ketone, a VOC widely used in the printing industry, on activated carbon in a supercritical CO2 environment at pressures in the range of 10 MPa to 20 MPa and temperatures between 313 K and 353 K, which provides a wider range of equilibrium adsorption data for diethyl ketone under different pressure and temperature conditions and allows a comparative analysis with other ketone VOCs. It is found that the equilibrium adsorption of diethyl ketone on activated carbon exceeds that of methyl ethyl ketone, probably due to differences in their respective affinities for activated carbon and their different volatilities in a supercritical fluid context. The Dubinin-Astakhov model was used to interpret the data and showed an average relative deviation of approximately 3.8 % between modeled and observed values. Additional analysis of the model parameters influenced by CO2 density and VOC characteristics was performed to gain a better insight into the adsorption dynamics and to contribute to the design and improvement of the activated carbon regeneration process. [Display omitted] •Adsorption equilibria for diethyl ketone on activated carbon in supercritical CO2 are reported.•Adsorption equilibria depend strongly on CO2 density and molecular structure of VOCs.•Adsorption equilibria are characterized by Dubinin-Astakhov equation with two fitting parameters.•The model parameters allow quantitative understanding of adsorption phenomena.