METHOD OF NEUTRALIZATION OF THE SULFIDE-CONTAINING ALKALINE SOLUTIONS Russian patent published in 2008 - IPC C02F1/72 C02F103/24 C02F103/28 

FIELD: oil-processing industry; chemical industry; tanning industry; pulp-and-paper industry; other industries; methods of neutralization of sulfide-containing alkaline solutions.

SUBSTANCE: invention is pertaining to the field of chemical technologies and may be used for purification of the enterprises of alkaline solutions of sulfides at firms of oil-processing, chemical, pulp-and-paper, tanning and other industries. The method of neutralization of sulfide-containing alkaline solutions with production of the elemental sulfur provides for treatment of the solution containing up to 100 g/l of metals sulfides with the molecular oxygen and-or the air in the presence of the hydrogen sulfide oxidation catalyst. Process is exercised in two phases - at the first phase at рН ≥ 11 oxidization is conducted till the oxygen absorption corresponding to the molar ratio of O₂ /S² = 0.5÷0.7, and at the second phase feeding of the oxygen and-or the air terminate and acidate the solution to рН = 3÷5. The method is exercised at the temperature of no less than 20°С and the air pressure of no less than 0.1 MPa. The method ensures the complete transformation of sulfides into element sulfur, simplification of the production process of oxidization of the spent sulfuric alkaline solutions and reduction of the power input.

EFFECT: invention ensures the complete transformation of sulfides into elemental sulfur, simplification of the production process of the spent sulfuric alkaline solutions oxidization and reduction of the power input.

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