Electrically Regenerated Ion Exchange for Removal and Recovery of Cr(VI) from Wastewater

Abstract

Ion exchange is widely used for removal and recovery of Cr(VI) from wastewater. Generally, the exhausted ion exchanger is regenerated using chemicals. Although chemical regeneration is efficient, contaminants are introduced, leading to difficulty for the subsequent recovery of Cr(VI). To overcome such a problem, a new regeneration method, namely electrical regeneration, which is carried out on the principle of electrodialysis, is presented in this paper. Experimental results showed that the weak-base resin used could be effectively regenerated electrically. About 93% capacity of the resin was restored under a constant current of 0.25 A over a period of 24 h. The pure chromic acid was recovered in the anode chamber with a concentration of 5.03 g Cr(VI)/L. It was found that the weak-base resin regenerated electrically could remove Cr(VI) from wastewater as effectively as that regenerated chemically. The Cr(VI) concentration was reduced from initial 50 mg/L to lower than the detectable limit, 0.01 mg/L, after treatment.

Perfomance Evaluation of Fly Ash and Red Brick Dust for Recovery of Chromium From Tannery Wastewater by Adsorption Method

“…Of late the most widely recognized procedures for expulsion of chromium have been: filtration, reverse osmosis [9], adsorption and concoction responses i.e. lessening and precipitation [10] electro deposition, film frameworks and particle trade forms [11]. Ordinary techniques connected for chromium expulsion have numerous downsides.…”

Polymer Nanocomposites and Cr(VI) Removal from Water

“…Therefore, it is necessary to remove Cr(VI) from wastewater before it is discharged to the natural water bodies. Various treatment technologies such as ion exchange, electrolytic removal, membrane filtration, reverse osmosis, chemical precipitation, adsorption, and solvent extraction have been reported for the removal of Cr(VI) from waste water [25][26][27][28][29][30][31][32][33][34][35][36][37][38]. Most of these technologies are associated with high operational and maintenance cost.…”

Removal of heavy metals Pb(II), Cd(II) and Cu(II) from waste waters using synthesized chromium doped nickel oxide nano particles

“…Recent approaches for the removal of heavy metals from wastewaters have mainly included chemical precipitation, adsorption, oxidation-reduction, evaporation, ionic exchange, electrochemical treatment, and membrane separation techniques [9][10][11][12][13][14]. Adsorption is most commonly used for heavy metals remediation from water [15,16].…”