Triisooctylamine (TIOA) was used to extract Cr(VI) from several acid solutions of HC1, HBr, HN03 and HCI04. The results were divided into two groups according to the acid solutions used: HC1 and HBr, or HN03 and HC104. Chromium(VI) is extracted according to an ion-exchange reaction which has been found for amine-Cr(VI) extraction systems. However, the ion-exchange mechanism holds only at low acidities. At high acidities, Cr(VI) is coextracted with HC1 or HBr by TIOA. It was found that TIOA extracts Cr(VI) as Cr2OU from HC104 solution and as HCr04 from HC1, HBr, and NH03 solutions. An extraction model which could explain the distribution equilibria was proposed, and the extraction constants were then determined.
All Science Journal Classification (ASJC) codes
- Chemical Engineering(all)