Abstract: A method for extracting and recycling chromium from hexavalent chromium-containing residues includes the following steps: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding sodium sulfate, sodium chlorate and sulfuric acid to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; 6) precipitating the supernatant and the water used for washing the filtered residues with a precipitant CaCl2, then centrifugally washing, dewatering and drying the precipitates; and 7) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: A treatment method for resource recycling of hexavalent chromium-containing residues is provided. This method comprises steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding mineralizers to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; and the mineralizers are sodium chlorate, sodium perchlorate and hydrochloric acid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; and 6) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: The present invention discloses a treatment method for resource recycling of hexavalent chromium-containing residues, belonging to a field of a clean treatment and resource recycling of chromium-containing residues. This method comprises steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding mineralizers to a solution obtained in step 1) and stirring sufficiently to obtain a mixed liquid; and the mineralizers are sodium chlorate, sodium perchlorate and hydrochloric acid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; and 6) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.

Abstract: The present invention discloses a detoxification treatment method for extracting and recycling chromium from hexavalent chromium-containing residues, comprising steps as follows: 1) adding water to the hexavalent chromium-containing residues and mixing uniformly; 2) adding sodium sulfate, sodium chlorate and sulfuric acid to a solution obtained in step 1) and stirring, sufficiently to obtain a mixed liquid; 3) treating the mixed liquid by a hydrothermal method or direct heating; 4) after the heating treatment, naturally cooling a solid-liquid mixture to room temperature for holding; 5) separating solid residues and a chromium-containing supernatant, and washing filtered residues with water and then drying; 6) precipitating the supernatant and the water used for washing the filtered residues with a precipitant CaCl2, then centrifugally washing, dewatering and drying the precipitates; and 7) recycling a chromium-containing solution for returning to a work section, or for a treatment of recycling chromium.