Hybrid Membrane Technology for Acid Recovery from Wastewater in Coated Steel Wire Production: A Pilot Scale Study

Abstract

In the present study, the problem of sulfuric acid recycling from spent copper plating solution was solved using a hybrid membrane technology, including diffusion dialysis and electrodialysis. A real solution from the production of copper-coated steel wire, containing 1.45 mol/L of sulfuric acid, 0.67 mol/L of ferrous sulfate and 0.176 mol/L of copper sulfate, was processed. Diffusion dialysis with anion-exchange membranes was used to separate sulfuric acid and salts of heavy metals. Then, purified dilute sulfuric acid was concentrated by electrodialysis. The energy consumption for sulfuric acid electrodialysis concentration at a current density of 400 A/m2 was 162 W·h/mol, with a current efficiency of 16 %. After processing according to the hybrid membrane scheme, the solution contained 1.13 mol/L sulfuric acid, 0.077 mol/L ferrous sulfate and 0.022 mol/L copper sulfate. According to established requirements, the solution of a copper plating bath had to contain from 0.75 to 1.25 M sulfuric acid, 0.16–0.18 M of copper sulfate and ferrous sulfate not more than 0.15 M. The resulting acid solution with a small amount of ferrous sulfate and copper sulfate could be used to prepare a copper plating bath solution.

Comparison of Anion-Exchange Membranes for Diffusion Dialysis of Mixtures of Acids and Their Iron Salts

“…In recent years, several studies have been carried out on the regeneration of acid waste liquids by diffusion dialysis [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. In the literature [ 3 ], diffusion dialysis was used for the treatment of spent desoldering solutions with the content of tin, iron, copper, and lead in HNO 3 .…”

“…Zhang et al [ 11 ] proposed a pressure-concentration diffusion dialysis process to overcome the limitations of diffusion dialysis, such as low processing capacity and water osmosis. A combined hybrid membrane process of diffusion dialysis and electrodialysis was used to recycle sulfuric acid from the spent copper plating solution (containing FeSO 4 , and CuSO 4 ) [ 12 ] to treat battery recycling wastewater containing H 2 SO 4 and NiSO 4 [ 13 ] or to recover acids (hydrochloric, nitric, and sulfuric) from metallurgical acid wastewater containing Fe n+ salts [ 14 ]. In [ 15 ], a counter-current dialyzer with a Neosepta-AFN membrane was used to separate the model mixture of hydrofluoric acid and ferric nitrate and a real spent pickling solution.…”

“…Batch dialysis was used, for example, for the separation of an aqueous solution of HCl + FeCl 2 [ 16 ] or for the separation of an HNO 3 + Fe(NO 3 ) 3 mixture [ 17 ] using an anion-exchange membrane Neosepta-AFN. In the case of continuous processes, the most widely used type of membrane modules is the flat plate dialyzer [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]; however, spiral wound diffusion dialysis membrane modules have attracted much attention recently. A spiral wound module with the Fumasep-FAD membrane was, e.g., used to separate H 2 SO 4 and Cu 2+ and Fe 2+ salts [ 18 ] and to separate HCl and Zn 2+ , Cr 3+ , Ni 2+ , and Fe 2+ salts [ 19 ].…”

Treatment of Spent Pickling Solutions by Diffusion Dialysis Using Anion-Exchange Membrane Neosepta-AFN

“…In recent years, there have been several studies on the regeneration of waste solutions by diffusion dialysis [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Lan et al [ 3 ] published results on the recovery of HNO 3 from acid effluents discharged by an electrodialysis plant.…”

“…The recovery of rare earth elements from electronic waste by diffusion dialysis was investigated by the authors [ 17 ]. In the latest study [ 18 ], the problem of sulfuric acid recycling from spent copper plating solution (containing H 2 SO 4 , FeSO 4 , and CuSO 4 ) was solved using a hybrid membrane technology. Diffusion dialysis was used to separate sulfuric acid and salts of heavy metals and then purified dilute sulfuric acid was concentrated by electrodialysis.…”