Method of continuously treating sexivalent chrome

Abstract

Abstract PURPOSE: To precipitation separate sexivalent Cr as Cr(OH) 3 , by completely reducing sexivalent Cr by pouring a liquid containing Fe 2+ so that the oxidation-reduction potential of the system be held in a limited range while specifying the pH of a solution or suspension containing sexivalent Cr. CONSTITUTION: A liquid containing Fe 2+ is poured so that the oxidation-reduction potential of the system be held to approx. -50W-150 mV -preferably, approx. -50W 100mV- of a solution or suspension containing sexivalent Cr in approx. 4.5W8.5 - prferably, approx. 5.5W7.2. Sexivalent Cr is reduced to trivalent Cr by the following reaction while being coagulation precipitated as Cr(OH) 3 . Cr 6+ +3Fe 2+ →Cr 3+ +3Fe 3+ Cr 3+ +3OH- →Cr(OH) 3 Fe 3+ +3OH- →Fe(OH) 3 . COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Hiroyasu Kanesashi
• 👤 Kenichi Mitomo
• 👤 Nobuyuki Watabe

Bibliographic Details