Abstract: An ion exchange separation, recovery and regeneration process for the control of iron is disclosed that can replace the conventional bleed stream process used in copper electrowinning. The disclosed process minimizes the loss of cobalt from the electrowinning circuit and can effect a lowering of the total iron concentration in the electrolyte circuit with an associated increase in current efficiency. The process captures the iron as iron(III) on an ion exchange medium containing a plurality of --CH(PO.sub.3 R.sub.2).sub.2 or --C(PO.sub.3 R.sub.2).sub.2 -- groups through which the divalvent metal ions pass. The iron(III) is then reduced with copper(I) to form iron(II) that is freed from the exchange medium, thereby permitting regeneration of the medium.

Abstract: A process and apparatus for separating tritium from an aqueous solution that contains one or more additional dissolved radionuclides is disclosed. In accordance with the process the aqueous solution as a first liquid phase is contacted with each of three layers as a solid phase within a column. A first layer comprises particles having a plurality of pendent methylene diphosphonate groups. A second layer comprises strongly basic anion exchange particles, and a third layer comprises polymer particles free of ionically charged groups. The contact is maintained until a second liquid phase is formed that contains tritium as substantially the only radionuclide, and that second liquid phase is collected and can then be counted to determine the amount of tritium present. The column with its three layers constitutes the separation apparatus.

Abstract: An extraction chromatographic material for extracting metal cations from a liquid stream. The extraction chromatographic material is prepared by adsorbing a diesterified methanediphosphonic acid on an inert particulate support.

Abstract: An ion exchange separation, recovery and regeneration process for the control of iron has been developed to replace the conventional bleed stream process used in copper electrowinning. The process minimizes the loss of cobalt from the electrowinning circuit and strips the iron into a sulfate-based solution suitable for leach solution makeup. In addition, this process can effect a lowering of the total iron concentration in the electrolyte circuit with an associated increase in current efficiency.

Abstract: A process for preparing 4,4'(5')-[di-t-butyldicyclohexano]-18-crown-6 containing an enhanced amount of an isomer that extracts strontium ions from aqueous solution is disclosed. According to the process, an anhydrous reaction mixture is prepared containing 4,4'(5')-[di-t-butyldibenzo]-18-crown-6 as substrate dissolved in a C.sub.2 -C.sub.6 alcohol-containing solvent that can also contain benzene, toluene or xylene, a C.sub.2 -C.sub.6 carboxylic acid or anhydride and a 5 percent of rhodium on alumina particle catalyst. The resulting reaction medium is hydrogenated at about 200-1000 psi, at a temperature of about 35.degree.-120.degree. C. for a time period sufficient to reduce at least 90 percent of the substrate.