CO2 Separation from Syngas by Multiwall Carbon Nanotube

Abstract

In this study the equilibrium uptakes of hydrogen and carbon dioxid as the main constituents of syngas by the multi-walled carbon nanotube (MWCNT) were investigated at the temperature range of 288-318 K and pressure up to 40 bars. The results have shown that temperature had much less effect on the adsorption of H2 on MWCNT than adsorption of CO2. Several model isotherms such as Langmuir and Freundlich were examined to fit the equilibrium uptake data. The kinetics of H2 and CO2 adsorption on MWCNT were also investigated and the results revealed a fast sorption kinetic for both gas adsorption on MWCNT. Isosteric heat of adsorption was evaluated based on the Clausius–Clapeyron equation at different temperatures. Small values of isosteric heat of adsorption confirmed that although the adsorption of H2 and CO2 on MWCNT were exothermic, but the heat of adsorption was too low, therefore the process of adsorption of both gases on the MWCNT used in this study is physisorption.

Keywords

• Syngas
• Adsorption
• MWCNT
• Kinetic
• Isosteric heat