METHOD FOR DEMERCURISATION OF FLUORESCENT LAMPS Russian patent published in 2014 - IPC C22B43/00 C22B7/00 C22B3/04 

FIELD: chemistry.

SUBSTANCE: method for demercurisation of fluorescent lamps includes breaking down said lamps and treating the wastes under a layer of a demercurisation solution prepared in advance, washing and sorting the wastes. The demercurisation solution is prepared through synthesis of calcium polysulphide formed in a demercurisation apparatus at 50°C from lime and sulphur in ratio of 1:2 with sulphur concentration of 51-100 g/l. An anionic surfactant in the form of alkyl sulphate is added to the solution in amount of 5% of the weight of lime and a nonionic surfactant in the form of sintanol (oxyethylated alcohol) is also added to the solution in amount of 10% of the weight of lime. After treating the wastes, the spent solution is discharged from the demercurisation apparatus, followed removal of mercury sulphide therefrom and feeding into a storage container, from which the purified solution is fed for preparing washing liquid.

EFFECT: providing complete desorption of mercury from the glass surface, preventing decomposition of calcium polysulphide during preliminary storage before use, high ecological cleanness and efficiency of recycling fluorescent lamps by providing a closed recycling cycle.

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