**17. Ion exchangers of functional iminodiacetate groups**

**13. Ion exchangers of functional formazane groups**

14 Ion Exchange - Studies and Applications

however, their sorption capacity towards Cu(II) ions was close to zero.

**14. Ion exchangers of functional cyclane groups**

**15. Ion exchanger Metalfix Chelamine**

catalysts, etc. [93–98].

**16. Polyorgs ion exchangers**

Chelating ion exchangers of functional formazane groups [88–91] based on the styrene divinylbenzene skeleton [58], amino- and chloromethylated polystyrene [91], cellulose [58, 91], saccharose [65] and methacrylate [58] were applied for sorption and separation of platinum metals, gold, mercury, silver and copper. The sorption capacity towards Pd(II), Ag(I) and Hg(II) ions was in the range 0.05–0.06 mmol/g, 0.4–0.9 mmol/g and 0.6–0.8 mmol/g, respec‐ tively, for formazane ion exchanger based on cellulose, aminomethylated polystyrene;

For separation and recovery of Pd(II), Pt(IV) and Au(III), Jermakowicz-Bartkowiak [92] used the resin A7C prepared by the reaction of cyclane (1,4,8,11-tetraazacyclotetradecane) with the copolymer of vinylbenzyl and divinylbenzene chloride (VBC/DVB) obtaining the following sorption capacities: 47.4 (S0), 47.4 (S1) mg Au(III)/g, 48.1 (S0), 47.5 (S1) mg Pt(IV)/g, 26.0 (S0), 25.6 (S1) mg Pd(II)/g resin, where S1 – the multifunctional system, S0 – the single component system (static method) and 0.92 mmol Au(III)/g, 0.66 mmol Pt(IV)/g, 0.9 Pd(II) mmol/g dry resin (dynamic method). Desorption of Au(III), Pt(IV) and Pd(II) ions from the resin was made using a 5 % thiourea solution in 0.1 M hydrochloric acid with the yield 98, 97 and 98%.

The studies of the use of the ion exchanger Metalfix Chelamine of tetraethylenepentamine ligands (1,4,7,10,13 – pentaazatridecane) in the process of recovery, concentration and separation of platinum metal ions, gold and their accompanying elements from the environ‐ mental samples, anodic sludges from the electrorefining of copper ores, spent car exhaust gas

Polyorgs type chelating ion exchangers [58, 99–103] are used for separation, concentration and removal of palladium(II) ions and other noble metals from deposits, rocks, ores, minerals and industrial waste waters. The Polyorgs sorbents were prepared by introducing e.g. imidazole, pirazole, mercaptobenzothiazole, amidooxime groups to the macroporous copolymers (polystyrene, polyvinyl, polyacrylonitrile) and other matrices. Sorbents of this type are characterized by high chemicals stability in strong acid and alkaline solutions as well as high thermal resistance and can be applied in the whole pH range. The sorbents of Polyorgs type (11-n, 15-n, 17-n and 33-n) were also used for filling fibres e.g. polyacrylonitrile (PAN), Recovery of palladium ions from chloride and chloride-nitrate(V) solutions using the ion exchanger Amberlite IRC-718 of functional iminodiacetate groups and polystyrene skeleton was conducted by Hubicki et al. [104]. The largest total ion exchange capacities of Amberlite IRC-718 were obtained in the 0.1M HCl (1.099 mmol/g) and 0.9M HCl–0.1M HNO3 (0.693 mmol/g) solution. The additional of 1M AlCl3, 1M CuCl2 or 1M NiCl2 results in significant drop of ion exchange capacity.

Studies of Amberlite IRC-718 selectivity towards Pd(II), Pt(IV) and Au(III), Ti(IV), Ag(I), Al(III), Co(II) and Fe(III) were carried out also by Park and co-workers [105]. The optimal sorption conditions for Pd(II), Pt(IV) and Au(III) ions are pH = 0.1–4 and a flow rate ≤ 2 cm3 / min. Quantitative desorption of noble metal ions was conducted using 20 cm3 of 0.25 M thiourea and a flow rate 1 cm3 /min. The ion exchange capacity of the studied ion exchanger was 0.34 mmol Pt(IV)/g; 0.69 mmol Au(III)/g and 0.55 mmol Pd(II)/g of the resin. From a practical point of view, the chelating ion exchanger Amberlite IRC-718 can find application in removal, concentration and separation of noble metal ions from the solutions originating from hydrometallurgical processing of car exhaust gas catalysts, anodic sludges, wastewaters as well as in removal and determination of gold(III) ions in printed computer plates PCP [105].
