METHOD OF PRODUCTION OF SORBENT FOR SEWAGE TREATMENT FROM HEAVY METAL IONS Russian patent published in 1995 - IPC

FIELD: sewage treatment. SUBSTANCE: hydrochloride solution with pH=1 is prepared, then ferrous chloride and iron chips are introduced in the solution, iron chips are oxidized to relation Fe (III)Fe_com (0.3-0.35):1. Then, chrome- containing rinsing waters are introduced in the solution, with chrome ions (YI) satisfying the relation of ions of Cr(YI)Fe(III) as 1:1, and pH=2.0-2.5 is set. Ions of chrome (YI) are oxidized until relation Fe(III)/Fe_com(0.35-0.45) is attained and pH=4-5. Then, alkali is added to pH= 9-10. Method provides for production of magnetite-chrome sorbent for treatment of rinsing water containing ions of heavy metals, for instance, chrome, nickel, zinc. EFFECT: reduced cost and enhanced versatility, since it doesn't need expensive and difficult-to- get-at products. 3 tbl