There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Kenji Sumida, David L. Rogow, Jarad A. Mason, Thomas M. McDonald, Eric D. Bloch, Zoey R. Herm, Tae-Hyun Bae, Jeffrey R. Long

Carbon Dioxide Capture in Metal–Organic Frameworks

Application of low-cost adsorbents for dye removal – A review

Since the time of the industrial revolution, the atmospheric CO(2) concentration has risen by nearly 35 % to its current level of 383 ppm. The increased carbon dioxide concentration in the atmosphere has been suggested to be a leading contributor to global climate change. To slow the increase, reductions in anthropogenic CO(2) emissions are necessary. Large emission point sources, such as fossil-fuel-based power generation facilities, are the first targets for these reductions. A benchmark, mature technology for the separation of dilute CO(2) from gas streams is via absorption with aqueous amines. However, the use of solid adsorbents is now being widely considered as an alternative, potentially less-energy-intensive separation technology. This Review describes the CO(2) adsorption behavior of several different classes of solid carbon dioxide adsorbents, including zeolites, activated carbons, calcium oxides, hydrotalcites, organic-inorganic hybrids, and metal-organic frameworks. These adsorbents are evaluated in terms of their equilibrium CO(2) capacities as well as other important parameters such as adsorption-desorption kinetics, operating windows, stability, and regenerability. The scope of currently available CO(2) adsorbents and their critical properties that will ultimately affect their incorporation into large-scale separation processes is presented.

Adsorbent Materials for Carbon Dioxide Capture from Large Anthropogenic Point Sources

https://persianmof.weebly.com/uploads/4/8/8/3/48832931/chem._rev._2014,_114,_10575.pdf

Water stability and adsorption in metal-organic frameworks.

This work examined in detail the a priori prediction of the axial dispersion coefficient from available correlations versus obtaining both it and mass transfer information from experimental breakthrough data and the consequences that may arise when doing so based on using a 1-D axially dispersed plug flow model and its associated Danckwerts outlet boundary condition. These consequences mainly included determining the potential for erroneous extraction of the axial dispersion coefficient and/or the LDF mass transfer coefficient from experimental data, especially when nonplug flow conditions prevailed in the bed. Two adsorbent/adsorbate cases were considered, i.e., CO2 and H2O vapor in zeolite 5A, because they both experimentally exhibited significant nonplug flow behavior, and the H2O-zeolite 5A system exhibited unusual concentration front sharpening that destroyed the expected constant pattern behavior (CPB) when modeled with the 1-D axially dispersed plug flow model. Overall, this work showed that it was...

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Limitations of Breakthrough Curve Analysis in Fixed-Bed Adsorption

Carbon–silica composite adsorbent: Characterization and adsorption of light gases

MCM-41 impregnated with active metal sites: Synthesis, characterization, and ammonia adsorption

Experimental data are reported for adsorption of ethane and propane and their mixtures with water on BPL activated carbon. Pure alkane isotherms were measured at 273, 298, and 323 K from the Henry's law region to approximately atmospheric pressure. Mixture data, including hysteresis measurements, were obtained at 298 K by fixing the water partial pressure (or relative humidity). Alkane adsorption is significantly affected by water, with loading reductions of up to 60% at a relative humidity of 50%. The results show that alkanes do not adsorb independently of water, and greater loading reductions can be expected at higher relative humidities. Also, from the data we deduce that approximately 6% of the adsorbent surface strongly adsorbs water, probably on oxide sites. Pure alkane isotherms are analyzed in terms of a lattice model, and a simple empirical method is proposed for calculating mixture equilibria from pure-component isotherms. The method is applied to the data as well as to data for other organic-water mixtures adsorbed on BPL carbon. Results are compared with predictions of previously published methods.

M. Douglas LeVan

Papers

Limitations of Breakthrough Curve Analysis in Fixed-Bed Adsorption

Carbon–silica composite adsorbent: Characterization and adsorption of light gases

MCM-41 impregnated with active metal sites: Synthesis, characterization, and ammonia adsorption

Coadsorption of Organic Compounds and Water Vapor on BPL Activated Carbon. 3. Ethane, Propane, and Mixing Rules

Adsorption equilibrium modeling for water on activated carbons