| 摘要 |
<p>The ion exchange resins have the repeating units: where B = halogen, -CH, -NH2, -SH, AsH2, -OR, -N(R) -R, -SR, -As(R)-R where R is a radical with C chain, m = 0,1,2,3 or 4, X = S, O, Se, Te, -NH- or (CH2)n where n is 1-4, W = -CH2- or -SO2-, Y = H, alkyl, alkenyl, or opt. substd. aryl and the gp. -NH-Z may be a gp. NH3+A- where A- is an anion equivalent. Prefd. materials are chloroalkylated or chlorosulphonated styrene-divinylbenzene macrophoric resins. Prodts. are esp. useful for selective absorption of Pt gp. metals and Au from strongly acid solns. contg. these. The metals can be recovered e.g. by elution of the resin with a suitable complexing agent such as thiourea.</p> |
