Radiation-flotation purification of aqueous wastes from mercury

Purification of industrial wastes of plants producing chlorine and alkalies by electrolysis with using metallic mercury as a cathode from mercury (in ionic and metallic form as well as in the form of precipitate) to the accepted in the Soviet Union limiting permitted level of concentration (5 x 10-3 mg dm-3) by routine sulphide and ion exchange methods has some disadvantages. We have now developed the radiation-flotation method which consists of three stages: preliminary flotation in the presence of surfactant (sodium alkylsulphonate), γ-irradiation at dose 1 kGy and secondary flotation (also in the presence of sodium alkylsulphonate). The method is discussed and results are reported. (author)