Many important industrial separation processes based on adsorption operate close to saturation. In this regime, the underlying adsorption processes are mostly driven by entropic forces. At equilibrium, the entropy of adsorption is closely related to the enthalpy of adsorption. Thus, studying the behavior of the enthalpy of adsorption as a function of loading is fundamental to understanding sepa...

The adsorption of volatile organic compounds (VOCs), exemplified by benzene and methylethylketone (MEK), onto seven different types of activated carbon was investigated. Results show that for benzene adsorption the adsorption characteristic energy, enthalpy, free energy and entropy are in the range 17.12-36.86, -20.8 to -44.7, -11.89 to -16.22 kJ/mole and -29.4 to -85.3 J/mole/K, respectively. ...

Porous materials adsorb H2 through physisorption, a process which typically has a rather low enthalpy of adsorption (e.g. ca. 4 to 7 kJ mol(-1) for MOFs), thus requiring cryogenic temperatures for hydrogen storage. In this paper, we consider some of the issues associated with the accurate characterisation of the hydrogen adsorption properties of microporous materials. We present comparative gra...

the effect of temperature on the adsorption of heavy metals on not only natural bulk clay, but also for the individual phases that composed the bulk clay sample, was investigated. combined adsorption- sequential extraction analysis (casa) for pb, cu, zn and cd were conducted under various temperatures that ranged from 150c to 550c. as a result, it was found that heavy metals adsorption for b...

The adsorption of CO on the supported gold nanoparticle catalysts Au/TiO2, Au/Fe2O3, and Au/ZrO2 was examined using infrared transmission spectroscopy to quantify the isobaric CO coverage as a function of temperature. The Temkin adsorbate interaction model was then applied to account for the adsorption behavior. To test the general applicability of the Temkin model, this treatment was also appl...

the effect of temperature on the adsorption of heavy metals on not only natural bulk clay, but also for the individual phases that composed the bulk clay sample, was investigated. combined adsorption- sequential extraction analysis (casa) for pb, cu, zn and cd were conducted under various temperatures that ranged from 150c to 550c. as a result, it was found that heavy metals adsorption for bulk...

Elution and solvation processes in liquid chromatography may be controlled by temperature changes. In the case of solvent adsorption, the temperature influences the amount of adsorbed solvent as well as the enthalpy and entropy of the solvation process. In this work, the thermodynamic parameters of organic solvents used as organic modifiers in the reversed-phase high-performance liquid chromato...

The interactions between lysozyme-imprinted hydrogel and their template protein were studied using adsorption measurements, competitive adsorption experiments, and isothermal titration calorimetry (ITC). The results were compared to the interactions between the imprinted polymer and a reference protein, cytochrome c. Experimental adsorption isotherms and competitive adsorption studies detected ...

Physisorption-based hydrogen (H 2) storage in microporous carbons has a trade-off between adsorption capacity and adsorption enthalpy [5]. Conceptually, this problem is best illustrated in terms of the ideal slit pore formed from two parallel, semi-infinite graphite slabs. Packing density is maximized when the pore width is several times larger than the diameter of the H 2 molecule, since it pe...

The study of aliphatic compounds adsorption on activated carbon can be carried out from the energetic change involved in the interaction; the energy values can be determined from isotherms or by the immersion enthalpy. Vapor phase adsorption isotherms of hexane at 263 K on five activated carbons with different content of oxygenated groups and the immersion enthalpy of the activated carbons in h...