A selective sorbent for concentrating noble metals.

New chelating sorbents have been synthesized by aminating chloromethylated styrenedivinylbenzene macroporous copolymers with 3(5)-methylpyrazole. The sorption of noble metals from acid solutions and the selectivity has been studied. The sorbents are of interest for selective concentration and extraction of the noble metals.

Arsenazo III and its analogues-VII Colour reactions of the rare earth elements with a new reagent-carboxynitrazo.

A new reagent, Carboxynitrazo, gives a colour reaction with some rare earth elements. For the individual rare earth elements the sensitivities of the reactions are very different. The difference is greatest for the elements of the Ce- and Y-subgroups.

Substoichiometric separation in activation analysis: extraction of co-ordinatively-unsolvated salts.

The necessary conditions have been examined for the use of extraction of coordinatively-unsolvated salts for substoichiometric separations in activation analysis, especially the influence of interfering ions and of the concentration of the carrier. A study has been made of the substoichiometric extraction of halide ions, oxyanions and anionic metal complexes by means of the tetraphenylarsonium ion into chloroform and dichloroethane, and of the extraction of alkali metal ions into nitrobenzene with tetraphenylborate. Substoichiometric extraction can be combined with neutron-activation analysis for the determination of traces of iodine, caesium, rubidium, manganese, rhenium, chromium, thallium, gold, gallium and tantalum.