Adsorption process selection matrix

The adsorption affinities of the hexagonal zirconia matrix toward Ni(II) and Cu(II), Cu(II) >>Ni(II), are opposite to those observed for LS samples [6] Ni(II) > Cu(II) (in this case the respective chlorides were used for both Ni and Co). This indicates that the nanostructure of the templated substrate can exert remarkable effects not only on the total amount of adsorbed cations, but also on the selectivity of the adsorption process. It could be inferred that hexagonal nanostructures, as well as lamellar ones, do not favor cobalt adsorption (or the adsorption of other cations with coordination number 6, forming octahedral compounds). However, lamellar nanostructures favor Ni(II) adsorption, whereas Cu(II) adsorption is favored by templated hybrid matrices with hexagonal nanostructures. 

Micellar flooding is a promising tertiary oil-recovery method, perhaps the only method that has been shown to be successful in the field for depleted light oil reservoirs. As a tertiary recovery method, the micellar flooding process has desirable features of several chemical methods (e.g., miscible-type displacement) and is less susceptible to some of the drawbacks of chemical methods, such as adsorption. It has been shown that a suitable preflush can considerably curtail the surfactant loss to the rock matrix. In addition, the use of multiple micellar solutions, selected on the basis of phase behavior, can increase oil recovery with respect to the amount of surfactant, in comparison with a single solution. Laboratory tests showed that oil recovery-to-slug volume ratios as high as 15 can be achieved [439]. 

In our view, genetic engineering of future enzymes for industrial uses should consider not only their catalytic properties, but also their potential for isolation and immobilization. Designing enzymes to allow selective, high affinity immobilization by adsorption on a relatively inexpensive matrix should greatly increase the attractiveness of enzyme bioreactor processes. 

Sorption effects by the gel matrix may alter the values of and for certain solutes, and the use of against log plots to select a gel, takes into account neither those effects nor zone spreading in the column, and variations in flow-rate (which could arise, for example, from differences in viscosity of sample and eluant). Taken together these may have an important effect on the separation, and hence on the choice of the best gel for a particular purpose. The behaviour of small molecules on tightly cross-linked gels is profoundly influenced by adsorption, ion exclusion, ion exchange and various other processes which dominate the size differences between solutes. 

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