Experimental Study on the Control of Wire Pickling Solution Concentration

Using diffusion dialysis technology, hydrochloric acid pickling solution from wire surface treatment is recovered. By adding new hydrochloric acid, the pickling solution maintains the concentration necessary for regular production, allowing continuous recycling in wire pickling to reduce the consumption of new hydrochloric acid. This study investigates the effects of the water-to-acid flow ratio, hydrochloric acid concentration, ferric chloride concentration, and receiving solution on the acid recovery rate and ferric chloride retention rate. The results indicate: (1) The water-to-acid flow ratio and receiving solution have little impact on acid recovery; (2) As the hydrochloric acid concentration increases, the recovery rate gradually decreases from 92% to about 85%, while the retention rate conversely increases from 75% to around 83%; (3) As the ferric chloride concentration increases, the recovery rate slowly rises, peaking at 92% when the ferric chloride concentration reaches 150 g/L, then slightly decreases, while the retention rate shows the opposite trend; (4) Recovered acid with a concentration of 238 g/L effectively treats rusted wire. The experiment confirms that diffusion dialysis technology can effectively reduce production costs and improve efficiency.