Study on the Efficiency of Hydrochloric Acid Recovery from Industrial Effluents by Distillation

This study aims to develop and evaluate a hydrochloric acid recovery system using evaporation. The efficient recovery of HCl from residual industrial streams is economically and environmentally important. In this instance, the effluent arises from a regeneration procedure involving an ion exchange resin implemented to eliminate antimony and bismuth from the electrolyte utilized in copper electrorefining. This effluent contains substantial quantities of these metals, which react with hydrochloric acid to form chlorides that have higher boiling points than hydrochloric acid. Additionally, arsenic is also pre-sent in the stream. To address this issue, evaporation experiments were per-formed at a specified temperature based on the boiling points obtained through prior analysis conducted within a laboratory setting. Laboratory-scale experiments results, obtained in a range between 110-140ºC, demonstrate a high efficiency (>80%) in HCl recovering from this industrial stream, with adequate purity for reuse into the process. Distillation of HCl concentrated the metals contained in the stream, allowing their recovery.