1. Determination of maximal amount of minor gases adsorbed in a shale sample by headspace gas chromatography. Author Zhang CY, Hu HC, Chai XS, Pan L, and Xiao XM Subjects Adsorption, Chromatography, Gas methods, Temperature, Ethane analysis, Natural Gas analysis Abstract In this paper, we present a novel method for determining the maximal amount of ethane, a minor gas species, adsorbed in a shale sample. The method is based on the time-dependent release of ethane from shale samples measured by headspace gas chromatography (HS-GC). The study includes a mathematical model for fitting the experimental data, calculating the maximal amount gas adsorbed, and predicting results at other temperatures. The method is a more efficient alternative to the isothermal adsorption method that is in widespread use today., (Copyright © 2013 Elsevier B.V. All rights reserved.) Published 2014 Full Text View/download PDF
2. A novel method for the determination of adsorption partition coefficients of minor gases in a shale sample by headspace gas chromatography. Author Zhang CY, Hu HC, Chai XS, Pan L, and Xiao XM Subjects Adsorption, Ethane analysis, Ethane chemistry, Models, Chemical, Particle Size, Temperature, Chromatography, Gas methods, Natural Gas analysis Abstract A novel method has been developed for the determination of adsorption partition coefficient (Kd) of minor gases in shale. The method uses samples of two different sizes (masses) of the same material, from which the partition coefficient of the gas can be determined from two independent headspace gas chromatographic (HS-GC) measurements. The equilibrium for the model gas (ethane) was achieved in 5h at 120°C. The method also involves establishing an equation based on the Kd at higher equilibrium temperature, from which the Kd at lower temperature can be calculated. Although the HS-GC method requires some time and effort, it is simpler and quicker than the isothermal adsorption method that is in widespread use today. As a result, the method is simple and practical and can be a valuable tool for shale gas-related research and applications., (Copyright © 2013 Elsevier B.V. All rights reserved.) Published 2013 Full Text View/download PDF