Solid-phase concentrations

Either low- or high-porosity-solids-phase concentrations can he formed in the purification and melting zones. End-fed units are characterized by low-porosity-solids packing in the purification and melting zones. 

Solid phase concentration of adsorbate i, mols i / g solid... 

In Table 10.2, this correlation is shown, comparing solid phase concentration calculated from the retention times of the fronts, and using the adsorption isotherm equation. 

Table 1. DTMF tailings average solid phase concentrations for 2008 boreholes.

The solid phase concentrations are influenced only by the rate of mass transfer, with convection and dispersion effects both being zero for this phase. 

Taking the balance, around both phases, effectively disregards the rate of solute transfer from liquid to solid and, instead, the assumption of a perfect equilibrium stage is employed to provide a relation between the resulting liquid and solid phase concentrations. For the special case of a linear equilibrium... 

In fixed bed columns (batch columns), the fluid and solid phase concentrations are functions of both position and time. Considering a conventional, idealized,... 

C = the adsorbate concentration of the liquid that is in equilibrium with the solid phase concentration q, and... 

Leyva et al. (2001) studied Sb(III) adsorption to hydroxyapatite. They conducted adsorption isotherms in closed vessels at Sb concentrations of 0.05-50 mg/L, constant I (0.01 m), constant solid phase concentrations of 10g/dm3 at pH values between 5 and 8. The hydroxyapatite was characterized by X-ray diffraction (XRD), SF.M-F.DS, X-ray photoelectron spectroscopy (XPS), and infrared (IR) spectroscopy. Langmuir adsorptions models revealed Fmax of 6.7 x 10 xmol/m2 and Xads = 1.5 x 103dm3/mol. As Sb adsorption occurred, the isoelectric point (pHicp) of the hydroxyapatite changed from 4.0 to 12.0. The decline in the pHjep during sorption as well as the absence of... 

Perrone et al. (2001) modelled Ni(II) adsorp-tion to synthetic carbonate fluoroapatite (CaI0 ((P04)5(C03))(0H,F). The solid phase had a pHIEP of 6.3 and a ZPC of 6.4 with an SSA of 8.8m2/g, an estimated sorption site density of 3.1 sites/nm2. They conducted 8-day isotherms in closed vessels at Ni concentrations of 5 x 10-10 to 1 x 10 8 M, constant I (0.05, 0.1 or 0.5 M), constant solid phase concentrations of 10 g/dm3 at pH values of 4 to 12. As Ni sorption occurred, no significant release of Ca was seen. Sorption was reversible. Rather than precisely characterize surface functional groups, they elected to describe their sorbent surfaces using acid-base reactions for the average behaviour of all sites involved in protonation and deprotonation. Potentiametric titration data were used to estimate the constants with the FTTEQL computer code ... 

Figure 4 illustrates the effect of different binding mechanisms on the porewater concentrations of metals and metalloid species in relation to the solid-phase concentrations. First, if a certain component were very soluble and not bound to the solid in any way, the pore water concentration at equilibrium would equal the total concentration in the system. However,... 

Here, equilibrium with C0. Dividing eqs. (4.13) and (4.16),... 

Table I could also represent the presence of salts of those elements. However, for the reasons given below, it was concluded that the solid-phase concentrations of rubidium, strontium and barium were probably the result of sorption rather than the presence of salts...

For both cesium and barium sorption, there is reasonable agreement between the total concentrations of desorbed species and the ion-exchange capacities determined by isotopic redistribution. The small differences which exist could easily be due to the precision in the elemental analyses. (Also, the experimental technique would not have detected desorption of hydrogen ions.) The solid-phase concentrations of sodium, potassium, magnesium, calcium. 

Concentrations and Solid-Phase Concentrations of Desorbed Species... 

Figures 1 through 5 should, therefore, be considered as representative values which (especially at values of Cj less than 10 mg-atom/ml) might be subject to variations on the order of 0.5 log units. Furthermore, the assumption that the solid-phase concentrations of rubidium, strontium and barium given in Table I represented the concentrations of sorbed species introduces further...

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