Relative sorption capacity

Fig. 13. Relative sorption capacity of proteins by carboxylic CP Biocarb-T vs pH of solution 1) terrilytin, 2) insulin, 3) chymotrypsinogen, 4) pancreatic ribonuclease, 3) pepsin, 6) thymarine, 7) thermolysine, 8) haemoglobin, P) lysozyme. mma, — quantity of protein bonden on Biocarb-T by pHma (...

Because the specific sorption capacity is defined as the mass of water adsorbed by the unit mass of a sorbent at given relative air humidity, the relative sorption capacity can also be given in terms of the moisture content. A filter paper, which features constant sorption capacity over the whole range of air humidities, was taken as a reference material. Hence, the parameter Xr in Eq. (12.21) is replaced with 0.01Xr,max, where is the maximum moisture content of the filter paper at 25°C. The constant 0.01 results from the definition of the mass transfer potential, where the specific sorption capacity of the reference material was assumed to be equal to 100 degrees of mass. 

Figure 12.8 shows a variation in the relative sorption capacity of several sorbents with the relative humidity of the environment, which represents the contribution of the partial pressure of absorbed moisture (sorbate) in the sorbent-air system. Using absolute values of the relative sorption capacity and... 

RguRE 12.8 Relative sorption capacity for some sorbents 1—peat 2—sawdust 3—wheat bran 4—ground rapeseed 5—potato starch 6—silica gel 7—activated carbon 8—zeolite. (Calculated from data by Nikitina, 1968.)... 

As illustrated in Figures 4.28a and 4.28b, carbonized fir fibers with a lower bulk density have a higher sorption capacity but a poorer cycling performance because the fiber entanglement is more fragile. In Figure 4.28c the relative sorption capacity S/Si, (ratio of sorption capacity in nth cycle to that in the first cycle)... 

FIGURE 4.28 Changes in sorbed amount of A-grade heavy oil for carbonized fir fibers and in recovered amount by filtration under suction, (a) Fibers with a bulk density of 5.5 kg/m, (b) fibers with a bulk density of 20 kg/m, and (c) changes in relative sorption capacity S/S, , and recovery ratio R/S with cycling time. 

If enough simulation data are available, separate distributions P ° (S) could be tabulated for each amount of connectivity. For example, high interstate connectivity can be correlated with higher relative sorption capacity [91]. By design, the resulting network will have a distribution of sorption coefficients that matches the desired target values. 

Sorption. The sorption properties of aluminum-deficient mordenite are strongly affected by the dealumination procedure used and by the degree of dealumination. Materials prepared by procedures that do not involve high temperature treatments show a relatively high sorption capacity for water (15,70), due to the presence of silanol groups, which are hydrophilic centers. However, aluminum-deficient mordenite zeolites prepared by methods requiring heat treatment show a lower sorption capacity for water due to fewer silanol groups. This was shown by Chen (71), who studied the sorption properties of aluminum-deficient mordenite prepared by the two-step method. 

In addition to anionic species, some metal cations can also be removed via adsorption processes with LDH materials. Recently, Lazaridis reported an interesting removal of two anions (P04 , SCN ) and three cations (Cd , Pb ", Ni " ) from aqueous solutions in single batch systems using uncalcined and calcined (773 K) Mg/Al LDH carbonate materials [148]. It was found that the calcined material showed higher sorption capacities than the uncalcined material for all the ions. Since the sorption capacities are relatively high, the author suggested that LDHs could be considered as a potential materials for sorption of both anions and cations in wastewater treatment systems. Seida et al. have also reported the rapid removal of dilute Pb from dilute aqueous solutions by a column packed with a pyroaurite-like Mg/Fe-COs LDH compound over a wide range of space velocity (Sv = 150-800 min" ) [149]. 

Kj, or the ratios of solution-phase solute concentration and adsorbed-phase concentration were calculated to estimate the relative affinity of the soils for phenolic acids. The Kj values for p-hydroxybenzoic acid, p-coumaric, vanillic, ferulic, and syringic icids were 67, 75, 69, 92 and 376, respectively for a 48-hr equilibration of 0.1 nmol mL phenolic acid solution with a sample of an alfisol preextracted in boiling water. The sorption capacity was greatly reduced by pretreatment of soil samples with sodium acetate-hydrogen peroxide to remove organic matter and metal sesquioxides. 

Soil biofilters are relatively large compared to filters using other media since soil pores are smaller and compounds have low permeability in soil. Soil biofilters also have limited depths due to problems associated with maintaining humidity in soil and minimizing pressure drop. Furthermore, soil sorption capacity is limited and residual contaminants are vented immediately to the atmosphere. 

The use of ion exchange resins and natural or synthetic inorganic exchange materials in the nuclear industry is well documented ( ). In the waste solidification application, the titanates or niobates offer no unique sorption properties. They do, however, provide a relatively high overall sorption capacity for a variety of nuclides in materials which can be converted into a stable ceramic host for the sorbed ions. After the sorption process, the column bed must be consolidated to reduce surface area. The project emphasis was directed toward a stable waste form and a considerable effort was devoted to producing and characterizing a highly dense form with favorable physical, chemical and thermal properties (l ). 

Sorption Capacity. The average sorption capacity of the clay determined from isotopic redistribution of Cs 37 between aqueous 0.01 M CsCl solutions and cesium-saturated clay was 0.9I mequiv./ gm. The average sorntion capacity similarly determined by isotopic redistribution of Ba3-33 vas 0.7U mequiv./gm. The maximum relative error in these capacities was estimated at 10%. 

For each nuclide studied, the sorption distribution coefficients appeared to result from a minimum of two separate mechanisms. In all cases, one mechanism appears to be an ion-exchange phenomena associated with the silicate phases and appears to have a relatively much larger sorption capacity than the other mechanism. In the case of cesium (and probably rubidium) the second mechanism appears to also be related to the silicate phases and may or may not be an ion-exchange phenomena. However, for the other elements studied, the second mechanism appears to be related to the hydrous iron and manganese oxides and again may or may not be an ion-exchange process. 

Depending on the types of hydrotalcites and the chemistry of the arsenic-contaminated waters, As(V) sorption capacities can be very good, perhaps more than 500 mg As(V) g-1 of hydrotalcite (Lazaridis etal., 2002, 321-322), or relatively poor (4.545 mg As(V)/uncalcinated hydrotalcite and 5.609 mg As(V)/calcinated hydrotalcite (Yang et al., 2005, 6809 Table 7.2). Even with excellent As(V) sorption abilities, hydrotalcites are rather expensive compared to aluminum (oxy)(hydr)oxides (Douhova et al.,... 

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