Determining Granular Activated Carbon Adsorption Isotherms of Benzene as a Volatile Organic Compound

Abstract

Abstract The determination of the adsorption equilibrium isotherm is a fundamental requirement for the design of adsorption-based processes. A method using a headspace auto-sampler and gas chromatograph system was developed in this study to determine the adsorption isotherm of benzene as a volatile organic compound for granular activated carbon. Dynamic equilibria between chemical solution, headspace gas and activated carbon were established in the 22-mL headspace glass vials sealed with Teflon-faced silicone septa and aluminum cramp caps. Using the closed system of headspace glass vials minimized the volatilization loss of chemical during the experiment. The method was utilized to measure the adsorption of benzene on Filtrasorb 300 granular activated carbon under 25 ± 1°C. The Freundlich isotherm parameters were determined using the experimental result. A reproducibility study and comparison with other results found in the literature showed that the method developed in this research is a reliable technique for determination of adsorption isotherm of benzene as a volatile organic compound on activated carbon.