**21. Chelating fibres**

It is worth presenting also the studies of using chelating fibres for the removal of platinum elements, for example, those Gong [115] and Li et al. [116] on application of fibres of functional imidazole groups in noble metal ions sorption. Bilba et al. [117] used chelating polyacrylami‐ doxime fibres in concentration and recovery of Pd(II) ions from chloride solutions. The attention should be also paid to the investigation by Gong and Wang [118, 119] as well as Chang et al. [120] on concentration of trace amounts of Au(III), Pd(II), Pt(IV) and Ir(IV) by means of chelating polyacrylacylaminothiourea fibres. Poly (acrylamidrazonehydrazide) [121] and poly (acryl-p toluenesulfonamideamidine-p-toluenesulfonylamide) [122] fibres were applied in quantitative concentration and separation of Au(III) and Pd(II) as well as Ru(III), Rh(III), Au(III) and Pd(IV) ions in the column system.
