title: Corresponding states interpretation of adsorption in gate-opening metal-organic framework Cu(dhbc)₂(4,4'-bpy).
abstract: The "universal adsorption theory" (UAT) extends the principle of corresponding states for gas compressibility to describe the excess density of an adsorbed phase at comparable reduced conditions. The UAT helps to describe experimental trends and provide predictive capacity for extrapolation from one adsorption isotherm to that of a different adsorbate. Here, we extend the UAT to a flexible metal-organic framework (MOF) as a function of adsorbate, temperature, and pressure. When considered via the UAT, the adsorption capacity and GO pressure of multiple gases to Cu(dhbc)2(4,4'-bpy) [H2dhbc=2,5-dihydroxybenzoic acid, bpy=bipyridine] show quantifiable trends over a considerable temperature and pressure range, despite the chemical and structural heterogeneity of the adsorbent. Exceptions include quantum gases (such as H2) and prediction of maximum capacity for large and/or polar adsorbates. A method to derive the heat of gate opening and heat of expansion from experimental trends is also presented, and the parameters can be treated as separable and independent over the temperature and pressure range studied. We demonstrate the relationship between the UAT and the common Dubinin analysis, which was not previously noted.
authors: Department of Energy & Mineral Engineering, The Pennsylvania State University, University Park, PA 16802, USA.
authors: Sarmishtha
authors: S
authors: Sircar
authors: Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.
authors: Sanhita
authors: S
authors: Pramanik
authors: Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ 08854, USA.
authors: Jing
authors: J
authors: Li
authors: Department of Physics, The Pennsylvania State University, University Park, PA 16802, USA.
authors: Milton W
authors: MW
authors: Cole
authors: Department of Energy & Mineral Engineering, The Pennsylvania State University, University Park, PA 16802, USA; Department of Chemical Engineering, EMS Energy Institute, The Pennsylvania State University, University Park, PA 16802, USA. Electronic address: adl11@psu.edu.
authors: Angela D
authors: AD
authors: Lueking
keywords: Adsorption; Gas separations; Gas storage; Porous coordination polymers