Säurechloride und Hydroxamsäuren von Carboxyl‐ Ionenaustauschern. 10. Mitteilung über Ionenaustauscher

Cross‐linked polymethacrylic acid resins are treated with thionyl chloride. Acid chloride and acid anhydride groups are thereby introduced into the resins. The carboxyl groups of resins of lower exchange capacity (with larger distances between neighbouring carboxyl groups) are transformed to a higher extent into acid chloride groups. Resins pretreated with thionyl chloride are reacted with hydroxylamine. Bifunctional cation exchangers with carboxylic and hydroxamic acid groups are obtained. As shown by measurements of ion exchange equilibria between heavy metal and H+ ions, these resins are highly selective for Fe3+, but little selective for Cu2+ and Zn2+ ions.