METHOD OF PURIFYING WATER FROM HEAVY METAL IONS Russian patent published in 2015 - IPC C02F1/62 C02F1/28 B01J20/14 C02F101/20 

FIELD: chemistry.

SUBSTANCE: waste water containing heavy metal ions is passed through a sorbent layer in the form of a pretreated natural zeolite. The zeolite is first annealed at 800-900°C for 45 minutes. The annealed sorbent is then treated with an acid solution with concentration of 0.5-1 mol/l for 1.5 hours at 30°C. The sorbent is then annealed for 1.5 hours at 600°C and treated with an alkali solution with concentration of 0.5-1 mol/l for 1.5 hours at 30°C. The alkali-treated sorbent is then annealed at 600°C for 1.5 hours. The initial sorbent used is Khotynetsky zeolite-containing tripoli.

EFFECT: high sorption capacity of the zeolite owing to thermochemical modification of the surface of the sorbent, which results in high degree of purity of water from harmful impurities.

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