Adsorption factor

Based on calculated soil adsorption factors (log Koc of 2.24, 2.98, and 4.3), hexachloroethane is expected to have medium to low mobility in soil (Howard 1989). Thus, leaching to groundwater could occur. Results of studies with low organic carbon (0.02%) soil material indicate that sorption to aquifer materials retards hexachloroethane migration in groundwater (Curtis et al. 1986). In aquatic environments, moderate to slight adsorption to suspended solids and partitioning to sediments is likely (Howard 1989). 

Algebraic Method for Concentrated Gases When the feed gas is concentrated, the absorption factor, which is defined in general as A = Lm/KGm and where K = t/°/x, can vary throughout the tower due to changes in temperature and composition. An approximate solution to this problem can be obtained by substituting the effective adsorption factors A, and A derived by Edmister [Ind. Eng. Chem. 35, 837 (1943)] into the equation... 

The nature of the solvent in liquid-phase alkyne hydrogenations and the extent to which it can influence the competitive adsorption factors needed to attain selectivity should also be considered. The semihydrogenation of 1-octyne over a series of Pd/Nylon-66 catalysts of varying metal load gave 1-octene with a selectivity of 100% over a wide range of metal loads when the reaction was run in heptane.38 n-propanol, however, reaction selectivity increased with decreasing metal load. Apparently the alcohol interacted with the catalyst to modify the active sites and influenced the relative adsorption characteristics of the acetylenic and olefinic species. This can affect reaction selectivity particularly if reactant diffusion assumes some importance in the reaction. 

The process of polymer adsorption is quite different in many aspects from that of small molecules the latter has been studied extensively in the past. These differences in their adsorption characteristics arise in turn from the obvious flexibility of the larger polymer molecules, so that in addition to the nsnal adsorption factors considered, such as the adsorbate-adsorbent, adsorbate-solvent, and adsorbent-solvent interactions, a major aspect to be understood is the conformation of polymer molecnles at the interface and its role in dispersion. Polymers have a large number of functional groups, each of which can potentially adsorb at the surface, whereas smaller molecules are mostly monofunctional. 

Specie j Adsorption heat AHaj (J.mol-1) Adsorption factor kaoj (dimensionless)... 

Use the Kremser equation with a molar stripping factor or molar absorption factor of F/Ffy m = 1.4. A molar stripping or adsorption factor = 5 is approximately the same... 

The results for the adsorption of crude oil on columns, and the BET surface area for the studied samples are summarized in Table 8.1. The adsorption factor (AF) is defined here as (oil mass)/(vermiculite mass). For both, expanded and FIV samples, the adsorption studies were performed at two different mass values 2.0 and 4.0 g. However, it was found that the AF values were not affected by the used vermicuHte mass. Adsorption experiments were also performed for hydrated (not expanded) vermiculite samples, and it was observed that the AF for these sample is very low (0.3). All adsorption experiments were performed in triplicate, and it was verified that the results are reproducible. 

The aim of this research is to show the influence of cross-flow model and ADPF model on the estimation of mass transfer coefficient, liquid hold up and adsorption factor by dynamic analysis of a TBR. 

The character (and nature) of adsorptioneil retention significantly differs from retention in an ideal liquid-gas system (see, e.g. [9]). Therefore, the use of an adsorptional factor m es it possible to achieve separations that are impossible or very difficult to realize in an ideal version of gas-liquid chromatography. 

Activated carbon fibers (ACFs) are a fibrous form of activated carbon with carbon content more than 90%. ACFs are relatively new adsorbents for filtration or purification techniques. The unique characteristics of ACFs compared with GAC and RAC could increase the application of activated carbons in various areas. The fiber shape of ACFs can significantly improve the intraparticle adsorption kinetics as compared with RAC and GAC, which are commonly employed in gas-phase and aqueous-phase adsorption. Therefore, ACFs adsorption is a promising technique used for designing adsorption units where intraparticle diffusion resistance is the dominant adsorption factor. As a consequence, the size of adsorption units can be decreased by using ACFs (Yue et al. 2001). 

Batch ailsoqitiiHi, negligible soUd-pfaase mass-transfer resistance If the quanti S/tnoi, an adsorption factor, is sufficiently large O rgc solid doses and equilibrium favorable to adsoiption), the solid-phase resistance can be neglected and only ki need be considered. These are the con[Pg.604]

Fig. 6 shows the analytical saturation and concentration profiles at 0.39 PV water injected for a case where mobile water is initially present. Initial water saturation is 0.4, indicated by Point i on Fig. 3. For this illustration, the adsorption factor b is 0.3. The frontal saturation (see Fig. 6) is determined by drawing a tangent to the polymer water fractional flow curve on Fig. 3 from a point on the saturation axis located at 5 = -0.3. The point of tangency is at = 0.478, = 0.892. The...

Such a test was performed with a solution of Kelzan M at the concentration which was used in the subsequent oil displacement experiments. The sand pack employed was a 24- x 5-in. glass tube packed with Simplots 135 Nevada sand. The resulting effluent concentration curve shown in Fig. 13 indicates an adsorption factor b of about 0.15. The specific adsorption of Kelzan M on the Nevada sand is 0.0025 Ib/cu ft PV. 

The circular and square points on Fig. 13 show the numerically calculated oil recovery curves for the two polymer floods with adsorption factor b = 0.13 and 0, respectively. A polymer water viscosity of 3 cp and polymer water relative permeability curve of 1/3, shown in Fig. 2, were used in the calculations. The linear portions of these two calculated recovery curves reflect the formation, high rate of travel, and production of the constant-saturation connate water bank (Fig. 4) ahead of the polymer front. Comparison with the experimental recovery curves shows that the numerical model predicts a considerably lower rate of production of the additional oil obtained by the polymer injection. The reason for this discrepancy is that the highly mobile connate water bank did not form in the experimental floods. The polymer water incompletely displaced and mixed with this connate water. 

The above-mentioned works, which describe the influence of the dyeing conditions on the kinetics of dye uptake, either ignore the dispersion or adsorption factor, or fail to define the flow velocity within the package. The details will be discussed in the next chapter. 

An important assumption, however, is assumption 6, since it separates convection and dispersion. Assumptions 7 and 8 aim to further incorporate the adsorption factor into the model. According to the theory and practice, these assrrmptions are reasonable. These basic assiunptions, and special definitions for some individttal cases, provide a basis for mathematical modelling of the dyeing process. 

Recently reported data [30] confirm primarily the equivalence of H2O, CO, O2 and CO2. The poisoning was studied at 350-400 and 450 °C, see Fig. 5.1. It was found [30] that the results could be described by adding an adsorption factor for oxygen to the rate equation, a procedure in accordance with Refs [28] and [20]. 

The kinetic network in Figure 5.7 includes separate pathways for N5 and N6 components and accounts explicitly for light production (C1-C5). This is critical to maintaining a good prediction of light gas components from industrial models. In addition, the adsorption factors include terms to account for hydrogen content, total pressure and adsorbed hydrocarbons. Additional work by Taskar et al. [4, 5] modifies this network to include the effects of catalyst deactivation. Table 5.4 shows the key rate equations for each class and the deactivation factor due to Taskar et al. 

Another significant feature is that the coke generation is rigorously modeled and included in the deactivation and adsorption factor F for each reaction. The deactivation factor is a function of reactor pressure, adsorbed hydrocarbons, coke on catalyst and acid/metal function of the catalyst This feature allows us to calibrate the model to a variety of operating conditions and catalyst behavior. In this work, we model a CCR with a hydrotreated feed therefore, we do not include any significant changes in catalyst activity due to changes in add of the catalyst... 

General paraffin containing x carbon atoms (x> 1 q Combined adsorption factor due to metal function... 

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