METHOD FOR REGENERATION OF ELUATES OF SODIUM-CATION FILTERS Russian patent published in 2021 - IPC B01J49/00 C02F1/56 C02F1/58 

FIELD: chemical industry.

SUBSTANCE: invention can be used in the processing of waste solutions from the regeneration of sodium-cation filters in water treatment processes. The treatment of sodium-cation filter eluates containing sodium, calcium and magnesium chlorides is carried out with stoichiometric amounts of sodium hydroxide at the first stage and sodium carbonate at the second stage to obtain reaction products in the form of a suspension of magnesium hydroxide particles at the first stage and calcium carbonate at the second stage. The resulting particles are removed from the sodium chloride solution by clarification. At each stage, before clarification, the eluate is heated to 50-90°C and its stirring with 0.1% aqueous solution of copolymer flocculant vinyl ether diethanol or monoethanolamine with acrylate or methacrylate sodium or potassium within the general formula:

,

where R is NH₂ or -NH-CH₂-CH₂OH, R' is Н or СН₃, or CH3, Me is K or Na and n₁=30-70 mol. %, in the amount of 30-200 mg/l.

EFFECT: invention makes it possible to accelerate the processes of Mg(OH)₂ and CaCO₃ isolation, increase the degree of their separation from the eluate during clarification.

1 cl, 1 tbl, 1 ex