Chromium and zinc removal method for ferrous chloride solution

• Main Authors: ZENG XIANQIN, YE MING, JIANG YAOQUAN, PENG AIPING, XIE JUN, MA MULIN, LI LIANGBIN, HU ZHIHUA, LI FANGFANG
• Format: Patent
• Language: Chinese; English
• Published: 23.02.2018
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; CLEANING OR DEGREASING OF METALLIC MATERIAL BY CHEMICALMETHODS OTHER THAN ELECTROLYSIS; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; INORGANIC CHEMISTRY; METALLURGY

The invention discloses a chromium and zinc removal method for a ferrous chloride solution. The method includes the following steps that A, the pH is adjusted for removing chromium, sodium hydroxide or ammonium hydroxide is dropwise added into the ferrous chloride solution to adjust the pH of the solution to be 5-7, and filter pressing is carried out to obtain chromium removing filter liquor withconcentration of Cr3+ not larger than 0.001 g/L; and B, sediment zinc removal is carried out, wherein ferrous sulfide powder with the water content being 30%-70% is added into the chromium removing filter liquor obtained after filter pressing in the step A, the water content is the mass percent, the adding amount of the ferrous sulfide powder is 6-12 times the amount of substance of Zn2+ in the chromium removing filter liquor, the reaction temperature is controlled to be 10 DEG C to 50 DEG C in the overall process, and a zinc removal solution with concentration of Zn2+ not larger than 0.01 g/Lis obtained through filte