A Zero-Emission Method For Recycling Phosphogypsum Using Na2so4 Electrolysis: Preliminary Study

A zero-emission method for recycling phosphogypsum using Na2SO4 electrolysis is investigated in this study. The phosphogypsum waster is converted to Ca(OH)(2) and Na2SO4. As prepared hydrated lime can meet the qualified product standard of Chinese National Standard (HG/T 4120-2009). NaOH and H2SO4 are electro-generated continuously by electrolysis. Incorporating a 2-D numerical model, the Na2SO4 electrolysis and the influences of operational conditions are studied particularly. The results demonstrate that higher Na2SO4 concentration, lower temperature and narrower electrode gap result in higher current efficiency. A lab-scale device has successfully been designed and fabricated.