The ion exchange behaviour of beryllium salicylate complexes.

As part of a general study of the co-ordination chemistry of beryllium, the beryllium salicylate complexes have been investigated by ion exchange procedures. The evidence indicates that a neutral 1 : 1 and an anionic 1 : 2 chelate exist in solution under appropriate conditions, and their stability constants have been determined by ion —exchange methods. The values of the stability constants were found to be β1 = 4.97 x 10 l2; and β2 = 2.63 x 10 22

Fission product separation from beryllium by ion exchange.

An ion—exchange process has been developed on the laboratory scale for the separation of low level fission product activity from beryllium in aqueous nitrate solution. A 97 per cent, recovery of beryllium with gross β and γ decontamination factors of 104 and 2 x 103 respectively has been demonstrated. The process is flexible and should be applicable to both sulphate and chloride media

The adsorption of beryllium on ion-exchange resins from inorganic systems.

Anion-exchange studies have revealed that beryllium forms anionic complexes with fluoride, phosphate, carbonate, and thiocyanate, the stabilities of these complexes lie in the order F-> H2P04- = CO3 = >> CNS-. Under the conditions of this investigation BeF4-2 and Be (H2P04)4-2 have been identified. Attempts to identify the carbonate complex were prevented by hydrolysis. The anionic thiocyanate complex is very weak and no attempt was made to identify this species. The anion -exchange data obtained in dilute nitric, hydrochloric, and sulphuric acid solutions showed some anionic complex formation but corresponding cation -exchange data have shown that in solutions of concentration up to 2.0M the extent of this reaction is negligible

SIAS, a computer program for the generalised calculation of speciation in mixed metal-ligand aqueous systems.

Computer program, SIAS, which calculates the concentrations of species in aqueous solutions of any complexity, is described. It is a corrected and augmented version of COMICS, which contains some errors and has an unsatisfactory output. Full details of the input required for the program and its output are provided and a complete listing is given

Laboratory studies of aqueous processes for the production of high purity uranium tetrafluoride from Australian leach liquor.

A modified form of the Power Reactor and Nuclear Fuel Development Corporation (PNC) process for the aqueous preparation of uranium tetra-fluoride from Australian Rum Jungle leach liquor was investigated. The commercially available tertiary amine mixture, Alamine-336, was substituted for the more costly tri-n-octylamine in the amine purification section of the process; the extraction was examined by batch simulation of the countercurrent extraction, washing and stripping stages. Alternative methods for reducing hexavalent uranium to the tetravalent state were examined and results on the use of powdered iron were encouraging. The use of hydrogen reduction appeared even more promising

Development of solvent extraction processes for the H.T.G.C.R. fuel cycle, Part 3 - chemical data for the extraction of actinides and fission products from aqueous beryllium sulphate solutions using amines.

Chemical data are presented for the actinides (uranium, plutonium and thorium), the fission products (cerium, zirconium, niobium and ruthenium) and beryllium in the extraction of these from beryllium sulphate solutions by amines, in particular Primene-JMT and Alamine-336. The data so obtained define the major chemical parameters requiring control in a solvent extraction process to decontaminate beryllium sulphate, and indicate that the use of the solvent Primene-JMT/Solvesso-100 will adequately remove the uranium, thorium, plutonium, cerium, zirconium and niobium without extracting significant quantities of beryllium. Ruthenium is not highly extractable and strontium and caesium are extractable only in trace quantity. Although this process will be adequate for primary decontamination of the beryllium sulphate, a further step to remove residual ruthenium, strontium and caesium may be required. The actinides with the extracted fission products are readily stripped from the amine phase with nitric acid, thus permitting recovery of the actinides by a conventional tributyl phosphate process. The amine phase is readily converted back to the free-base form using sodium carbonate. This is necessary to prevent recycling of the nitrate which would inhibit the extraction of thorium, plutonium and the fission products