N.S. W.(AustraliaJ DISCUSSION The formation of an intensely reddish-violet coloration when certain o&liSing agents are added to very dilute, slightly alkaline solutions of cupric salts containing dimethylglyoxime was first observed by CLARKE AND JONESI. This reaction was later modified and applied by HURD AND CI~AMBERS* for the calorimetric determination of copper. The use of dimethylglyoxime columns for the chromatagraphic separation of nickel from cobalt and other metals has been described by BURRIEL-MARTI and PINO-PEREZ*.
The investigation of the R, values of many metals, using butanol saturated with zN NH,OH and then with dimethylglyoxime a~ Solvent, was carried out and we found that a number of metallic climethylglyoxime complexes were formed, of which only the copper complex travels with the solvent.
This prompted investigation of the quantitative separation of copper by means of this solvent, using the paper-pulp strip technique as described by ANDERSON AND LEDERER for the chromatographic determination of thallium' and of gold*.
A liquid chromatogram was used to separate copper from the other metals by collecting the solvent which dripped off a strip of the paper-pulp. By this method, it was found possible to separate copper from silver, gold, platinum, rhodium, mercury and bismuth, and to estimate it in the filtrate, after suitable treatment, by electro-deposition. Qualitative examination of the filtrates revealed only traces of silver, rhodium, mercury and bismuth, while slight reactions were given by gold and platinum. The solvent was prepared by shaking 200 ml of butanol with 200 ml of zN NH,OH. Separation of the butanol layer yielded