Determination of gas mixture adsorption equilibria by the tracer-pulse technique

A Collection of More than 900 Gas Mixture Adsorption Experiments in Porous Materials from Literature Meta-Analysis

“…Examples that reported a range of adsorption conditions indicate the range of reported outcomes as error bars. This collection of data comes from 16 papers, − including three papers reporting replicate measurements with zeolite 13X ,, and two papers that report selectivity data from more than one material. , Out of the 16 materials reported, 13 are selective for ethane over ethylene, while zeolite 13X, Mg-MOF-74 and NUS-6­(Hf)-Ag are reported to be selective for ethylene over ethane. The results are consistent with the idea that MOF materials such as Mg-MOF-74 and NUS-6­(Hf)-Ag with open metal sites that have specific interactions with the pi-bond in ethylene can give C 2 H 4 /C 2 H 6 selectivity. , If the differences between independent replicates that are seen in Figure b for zeolite 13X are similar for other materials for which no replicates are currently available then it is difficult to say with any certainty which materials are the “winning” materials in terms of C 2 H 6 /C 2 H 4 mixture adsorption.…”

“…Examples that reported a range of adsorption conditions indicate the range of reported outcomes as error bars. This collection of data comes from 16 papers, 43−58 including three papers reporting replicate measurements with zeolite 13X 51,56,58 and two papers that report selectivity data from more than one material. 48,52 Out of the 16 materials reported, 13 are selective for ethane over ethylene, while zeolite 13X, Mg-MOF-74 and NUS-6(Hf)-Ag are reported to be selective for ethylene over ethane.…”

Gas adsorption isotherms from composition and flow-rate transient times in chromatographic columns I. Basic theory and a binary experimental test

“…This method is applicable to multicomponent mixtures. Danner et al (1980) have put it into practice using isotopically labelled tracers to cover the entire composition range for the adsorption of a binary gas mixture. The disadvantage of the tracer method is the need to obtain or manufacture the tracers, and the precautions that must be taken when using them.…”

“…In contrast to static methods, dynamic (chromatographic) methods make a per turbation to an equilibrium system and log certain variables, notably composition. The methods have several advantages such as speed and the relative ease with which conditions can be changed (see, for example, Conder & Young 1979;Danner et al 1980;Hyun & Danner 1985;Ruthven & Kumar 1980).…”

An automated multi-component gas adsorption system (MC GAS)

“…[20][21][22][23][24][25][26] Open systems also include concentration pulse chromatography, 27-32 zero-length column, [33][34][35] differential column method, 36 and others. [37][38][39] Open systems require careful determination of dead volume or holdup time, and at times require more involved analysis of experimental data to determine equilibrium loadings during an adsorption experiment.…”