# Application of Modern Research Methods for the Physicochemical Characterization of Ion Exchangers
## 3 Results and Discussion
### Optical Profilometry of Ion Exchangers
Due to the fact that the amount of ion exchange material on the core is very small, they are characterized by low capacity and can be easily overloaded, although they can produce very fast separations [65]. The fast ion exchange rate favours a sharp boundary in the column between the two zones formed by the exhausted resin and that in the initial ionic form, increasing the degree of column utilization. The SST cation resins reduce effectively fouling and leakage from Ca(II), Mg(II), Fe(III), Ba(II) and Sr(II), while the SST anion resins minimize greatly organic fouling and silica leakage. The technology is compatible with co-flow, counter-flow and packed bed systems, improving economic \begin{table}
\begin{tabular}{c c c} \hline
**Ion Exchanger** & **Surface Microgeometry Maps** & **Surface Microgeometry Maps** \\  & **(Middle Part of the Cut Beads)** & **(Edge Part of the Cut Beads)** \\ \hline Amberlite IRA 743 & & \\ Roughness parameters & R\({}_{\rm{a}}\)—771.44 nm \(\pm\) 104.91 nm & R\({}_{\rm{a}}\)—799.77 nm \(\pm\)108.78 nm \\  & R\({}_{\rm{q}}\)—986.66 nm & R\({}_{\rm{t}}\)—11.38 μm \\  & R\({}_{\rm{t}}\)—11.38 μm & R\({}_{\rm{t}}\)—11.14 μm \\  & & \\ Roughness parameters & R\({}_{\rm{a}}\)—751.34 nm \(\pm\) 102.18 nm & R\({}_{\rm{a}}\)—698.34 nm \(\pm\) 94.97 nm \\  & R\({}_{\rm{q}}\)—959.35 nm & R\({}_{\rm{t}}\)—895.70 nm \\  & R\({}_{\rm{t}}\)—10.95 μm & R\({}_{\rm{t}}\)—10.57 μm \\ \hline \end{tabular}
\end{table} 
Table 4: Surface microgeometry and roughness parameters of Amberlite IRA 743 before and after the sorption of Cu(II). and process results for softening and demineralization applications. In this group, Purolite Shallow Shell(tm) SSTPFA64, Purolite SST60H and Purolite SST80H are well-described. Equally interesting is the ion exchanger Amberlte IRA 743, selective towards boron, similarly to the other ion exchangers used for boron removal such as Lewatit MK 51 and Purolite S 110 [66; 67; 68; 69]. It contains the N-methylo-D-glucamine (NMDG) functional groups grafted on the ST-DVB skeleton and it is commonly used for the selective removal of boron in the form of trioxoboric acid or B(OH)\({}_{4}\)\({}^{-}\) ions from the sea water and wastewaters. Due to the presence of -OH groups closely attached in the cis position in the N-methyl-D-glucamine functional group, complexes are formed with H\({}_{3}\)BO\({}_{3}\) and its salts. Regeneration is affected by HCl or H\({}_{2}\)SO\({}_{4}\), lime or ammonia. This resin can be used for post-treatment desalination or production of ultrapure water. The efficiency of Amberlite IRA 743 resin is independent of temperature, pH and salinity. The group of the hybrid ion exchangers (HIXs) includes Purolite Arsen \(X^{\text{rp}}\), also known as FerriIX(tm) A35E--a strongly acidic macroporous cation exchanger based on the ST-DVB skeleton with the attached sulfonic acid groups and containing hydrated iron oxide nanoparticles for sorption of not only oxyanions AsO\({}_{4}\)\({}^{-}\), but also HPO\({}_{4}\)\({}^{2-}\), HSO\({}_{4}\)\({}^{2-}\), SCN\({}^{-}\), etc. [70; 71; 72; 73; 74; 75; 76]. In this group, there is also Lewat FO36--hybrid anion exchanger (HAIX) containing dispersed nanoparticles of hydrated ferric oxide (HFO) with Fe(III) and quaternary ammonium functional group (-\({}^{+}\)NR\({}_{3}\)) as well as Bayoxide(r) E 33 [71; 72]. They can be used for arsenic removal from potable water in which both arsenate As(V) and arsenite As(III) are safely adsorbed below 5 \(\mu\)g/dm\({}^{3}\). The hybrid polymeric-inorganic ion exchangers selective towards As(III,V) were introduced by [PERSON] and [PERSON] [73; 74; 75]. High concentration of the functional groups allowed large and fairly uniform loading of hydrated ferric oxide (HFO) particles (approximately 9-12% of Fe(III) by mass) within the polymeric beads. The additional advantage of such solution was simultaneous removal of not only As(III,V) ions, but also SO\({}_{4}\)\({}^{2-}\), Cl\({}^{-}\) and HCO\({}_{3}\)\({}^{-}\). As opposed to As(III,V) these competitive ions form only outer sphere complexes