Samples of vermiculite from Young River, W.A., and Kingaroy, Qld., have tested for cation exchange capacity using batch and column experiments. The better material, Young River vermiculite, was given more exhaustive column tests to determine the optimum particle size and to investigate its selectivity for caesium ions in the presence of higher concentrations of competing ions. At the optimum particle size of (-30+60) B.S.S. the cation exchange capacity of Young River vermiculite was approximately 70 meq/100g. With competing cations in solution caesium breakthrough occurs after a very small volume of influent has passed through the bed. It was concluded that neither of these vermiculite minerals would be suitable of medium level radioactive waste treatment.

Samples from possible zoolite bearing deposits have been tested for cation exchange capacity using batch and column experiments. The best material, Eagleton Quarry pink shale, was given more exhaustive column tests to determine the effect of mineral particle size, influent flowrate, and the presence of competing cations on caseium breakthrough. Diffusion of caesium ions through the mineral particle controls the ion exchange process. At the optimum size of (-30+36) B.S.S. the cation exchange capacity of Eagleton Quarry pink shale is approximately 60 meq/100g. With competing cations in solution the caesium breakthrough occurs after very small influent volumes have passed through the mineral bed and it was concluded that non of the minerals tested would be suitable for medium level radioactive waste treatment. A sample of clinoptilolite from Hector, California was also test for caesium selectivity.

This manual is intended to give operating and maintenance information for the range of counting equipment in use by the A.A.E.C. at Lucas Heights, designation of Scaler Type 2A. This equipment has been designed in the General Physics Section of the A.A.E.C. General Nucleonics Division. The equipment was built by an Australian manufacturer (Siemens Nucleonics).